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Mind

The is the complex ensemble of cognitive and psychological processes—including , , thought, , , , , and will—that enables subjective , , and with the in , particularly humans. It encompasses both conscious and unconscious faculties responsible for intellectual, affective, behavioral, and perceptual phenomena. From a neurological perspective, the mind emerges as an integrated function of the , often described as the "algebraic sum" of its diverse activities, dependent on neural networks for its operations. In , the mind has long been investigated through the mind-body problem, which probes the relationship between immaterial mental states—such as beliefs, desires, and —and the physical body, especially the brain. This debate originated prominently with ' 17th-century , which conceived the mind as a non-spatial, spiritual substance distinct from the material body yet interacting with it via the . Subsequent theories include , which reduces mental states to observable behaviors or dispositions; the mind-brain theory, equating mental events with neurophysiological processes; and , defining the mind by its causal roles in a system rather than its specific physical substrate. These perspectives grapple with issues like (the "aboutness" of thoughts), mental causation, and the —explaining why subjective experiences arise from physical processes. From a psychological and neuroscientific viewpoint, the mind is empirically studied as a collection of empirically observable processes, including , learning, and , often using folk psychology criteria to categorize human, animal, and even mechanical forms. Advances in imaging and since the 19th century, building on discoveries like cerebral localization by Broca and Wernicke, have solidified the as the organ of the mind, with disruptions such as damage leading to specific deficits like or . Contemporary research integrates , viewing mental states as informational processes that facilitate communication, control, and computation across disciplines like and . Ongoing inquiries explore how the mind develops, as in theory of mind—the to attribute mental states to others—and its implications for disorders like or .

Defining the Mind

Etymology and Historical Concepts

The English word "mind" derives from gemynd, meaning , thought, or remembrance, which stems from Proto-Germanic ga-mundiz (recollection, ). This term is linked to the men-, signifying "to think" or "to remember," reflecting an early association of the mind with cognitive faculties like and . In , the concept of mind evolved from broader notions of () to more differentiated intellectual capacities. , in his , proposed a division of the into rational (logistikon), spirited (thumoeides), and appetitive (epithumetikon) parts, with the rational soul governing reason and as the highest faculty. further refined this in De Anima, distinguishing nous ( or mind) into passive (nous pathetikos), which receives forms from sensory experience, and active (nous poietikos), which actualizes potential knowledge as a divine, separable aspect of the . During the medieval period, synthesized Aristotelian psychology with Christian theology in works like , positing a of souls: vegetative (for and growth in plants), sensitive (for and movement in animals), and rational (for intellect in humans), where the human uniquely encompasses all three as a infused by . This integration emphasized the mind's and its role in abstract reasoning, bridging pagan with doctrines of the immortal . René marked a pivotal shift in the early modern era with his substance , articulated in (1641), defining the mind as res cogitans (a thinking, non-extended substance) distinct from the body as res extensa (an extended, non-thinking substance), thereby prioritizing rational as the essence of mental life. Historically, conceptions of the mind transitioned from animistic beliefs in early civilizations—where natural phenomena and objects were attributed vital, mind-like forces—to more rationalist frameworks during the , emphasizing individual reason and mechanistic views of nature that set the stage for modern philosophical inquiries.

Contemporary Definitions

In contemporary philosophy and , the mind is often defined functionally as the ensemble of cognitive faculties that enable an to process and generate through causal interactions with its and internal states. This view posits the mind as comprising processes such as , which maps sensory inputs to representational states; , which stores and retrieves based on prior experiences; reasoning, which transforms inputs into outputs via rule-based or probabilistic computations; and volition, which initiates actions in response to these processes. These faculties collectively underpin mental states, where the of a state like or desire is determined by its role in a broader of input-output relations rather than its physical substrate. A key phenomenological dimension complements this functional account, emphasizing the as the locus of subjective —what it is like to undergo thoughts, feelings, and awareness from a first-person . articulated this in his seminal essay, arguing that involves an irreducible "what it is like" quality, as illustrated by the challenge of imagining the subjective world of a , which highlights the limits of objective descriptions in capturing or felt experiences. This aspect underscores that the is not merely a computational engine but a site of and lived phenomenology, where mental states possess a distinctive inner texture beyond behavioral or neural correlates. From a computational standpoint, the mind is conceptualized as an information-processing system analogous to a , where cognitive operations manipulate symbols according to formal rules to simulate intelligent behavior. This perspective, rooted in Alan Turing's 1936 framework for , has been adapted to by theorists like and , who propose that mental processes are realizable in any system capable of executing the relevant algorithms, whether biological brains or silicon-based machines. It frames as input decoding, as , and reasoning as algorithmic , providing a unified model for understanding across diverse substrates. This inclusive scope extends the mind to encompass both conscious deliberation—such as reflective —and automatic, unconscious processes like implicit learning or habit formation, while typically excluding purely physiological reflexes that lack representational content or adaptive flexibility. In , this distinction arises from empirical studies showing that much mental activity operates below , yet contributes to overall without qualifying as mere reflexive responses. Debates persist on the boundaries of the , particularly whether it should include as part of an "affective mind" integral to or restrict itself to neutral processing. Proponents of the affective argue that are evaluative mental states that modulate , , and reasoning, as seen in theories where or function as adaptive signals within the cognitive system. Critics, however, maintain a stricter cognitive boundary, viewing as bodily perturbations distinct from proper mental faculties, though contemporary views increasingly integrate them as essential to full mental functioning.

Aspects of the Mind

Consciousness and Unconscious Processes

The refers to the subjective of mental states characterized by phenomenal qualities, often termed , which encompass the "what it is like" aspect of sensations, emotions, and perceptions. These include elements such as , which selectively focuses cognitive resources on specific stimuli; , enabling reflection on one's own mental states; and , the directedness of mental states toward objects or events in the world. In terms, represent the intrinsic, first-person properties of that resist complete reduction to physical descriptions, as argued in analyses of subjective . Unconscious processes, by contrast, encompass mental activities that occur without subjective awareness but significantly influence behavior and . Influenced by Sigmund Freud's early formulations of the unconscious as a repository of repressed desires and motivations, modern has expanded this concept to include implicit cognition, where automatic, non-conscious mechanisms drive responses. Key examples include priming, in which prior exposure to a stimulus subtly facilitates or inhibits processing of related information, as demonstrated in semantic priming experiments showing faster recognition of associated words. Implicit biases represent another form, manifesting as unconscious stereotypes that affect judgments and interactions, often measured through tasks like the . Automatic further illustrates this, where heuristics and subliminal cues guide choices without deliberate deliberation, as evidenced in studies revealing unconscious influences on and preference formation. Experimental evidence highlights the precedence of unconscious processes over conscious awareness in initiating actions. In Benjamin Libet's seminal 1983 study, participants reported the timing of their conscious urge to flex a finger while brain activity was monitored via electroencephalography. The results showed a readiness potential—a slow negative shift in electrical activity—emerging approximately 350 milliseconds before the reported conscious intention, and up to 550 milliseconds before the actual movement, suggesting that unconscious neural processes initiate voluntary acts prior to subjective awareness. This finding has been replicated and extended, underscoring how much of human volition operates below the threshold of consciousness. Theories of interaction between conscious and unconscious processes propose mechanisms for how implicit activities gain access to awareness. Bernard Baars' , introduced in , posits that the mind functions as a collection of specialized unconscious modules that process information in parallel; consciousness arises when one module's output is broadcast to a global workspace, making it available for widespread integration, report, and control. In this model, unconscious processes compete for entry into the workspace, with winners achieving phenomenal experience while losers remain implicit, explaining phenomena like attention bottlenecks and the limited capacity of conscious thought. At the neural level, the plays a key role in modulating by facilitating the and amplification of signals from unconscious sources, enabling access to subjective . Review of intracranial studies indicates that prefrontal correlates with enhanced conscious , particularly in tasks requiring reportability or , though it does not solely generate . This overview aligns with broader that prefrontal regions act as a for broadcasting unconscious inputs, without implying exclusive localization of .

Mental Faculties and Modules

The mind encompasses several core faculties that serve as foundational building blocks for , including , , and reasoning. involves the integration of sensory information from multiple modalities to form coherent representations of the environment, enabling organisms to detect, discriminate, and respond to stimuli. , as delineated by , comprises distinct types: for personally experienced events with spatiotemporal context, for factual knowledge independent of personal experience, and for implicit skills and habits acquired through practice. Reasoning, in turn, operates through deductive processes that derive specific conclusions from general premises with certainty, inductive processes that generalize from specific observations to probable patterns, and abductive processes that infer the most plausible explanation for observed phenomena. A influential framework for understanding these faculties is the modularity hypothesis proposed by , which posits that the mind consists of domain-specific modules that process information semi-independently and automatically, particularly for input systems like and . These modules are hypothesized to be informationally encapsulated, fast-acting, and specialized, such as Noam Chomsky's (LAD), an innate mechanism that facilitates the rapid acquisition of grammatical structures in despite limited input. Empirical support for modularity comes from neuropsychological evidence, including dissociations in cognitive impairments where one faculty remains intact while others are affected. Illustrative examples highlight the specialized nature of these modules. In , the ventral stream processes object identity, form, and color for recognition ("what" pathway), while the dorsal stream handles spatial location and motion for guiding action ("where/how" pathway), as identified through lesion studies in primates. Similarly, , a key component of function, is modeled by Alan Baddeley's framework featuring a phonological loop for verbal information rehearsal, a visuospatial sketchpad for visual and spatial manipulation, and a central for and coordination. Although modular, these faculties do not operate in isolation; they integrate through mechanisms like , which selectively amplifies relevant information across modules, and , which involves monitoring and regulating one's own cognitive processes to optimize performance. Attention acts as a gatekeeper, binding features from perceptual modules into unified representations, while metacognition enables reflective oversight, such as evaluating the reliability of memory retrieval or adjusting reasoning strategies based on task demands. Developmentally, mental faculties emerge from a interplay of innate and learned elements, with infants demonstrating core knowledge systems for fundamental concepts like , number, and , as evidenced by Elizabeth Spelke's research using and violation-of-expectation paradigms. These innate systems provide an initial scaffold, which interacts with environmental experience to refine and expand faculties like reasoning and over time, supporting the transition from modular processing to more flexible, integrated .

Key Distinctions in Mental Phenomena

One of the fundamental distinctions in mental phenomena is intentionality, the directedness of mental states toward objects or contents. Franz Brentano introduced this concept in his seminal 1874 book Psychology from an Empirical Standpoint, positing that every mental act is characterized by the "intentional inexistence" of an object, meaning it refers to something as its content, whether real or imagined. This property sets mental phenomena apart from purely physical ones, as physical objects lack inherent "aboutness" or reference to external targets. For instance, a belief about a tree involves the mind directing itself toward the tree as its intentional object, even if the tree does not exist. Brentano's thesis, drawn from Aristotelian and Scholastic traditions, has become a cornerstone for distinguishing the mind's representational capacity from non-mental causation. Another key distinction lies in , the ineffable, subjective qualities of conscious experiences that resist full objective description. first employed the term "qualia" in his 1929 work Mind and the World Order, defining them as the "qualitative characters" immediately given in sensory experience, such as the vivid redness perceived in viewing a , which cannot be exhaustively captured by physical or behavioral terms. Qualia highlight the intrinsic nature of mental states, sparking debates like the scenario, where two individuals might have functionally identical visual systems yet swapped qualia for colors, underscoring the privacy and non-reducibility of subjective feel. This distinction emphasizes how mental phenomena involve phenomenal properties that are accessible only from the experiencer's viewpoint, beyond mere functional roles. Propositional attitudes represent mental states that relate individuals to propositions, such as beliefs, desires, and intentions, forming the explanatory framework of folk psychology. laid the groundwork for this in his 1892 essay "On Sense and Reference," analyzing how attitude reports like "John believes that is " involve cognitive relations to propositional contents, where substitution of co-referring terms fails due to differences in sense. These attitudes are typically expressed as relations to "that"-clauses (e.g., desiring that it rains), enabling predictions of behavior based on rational connections between them, like desiring an end implying intending means. In everyday reasoning, propositional attitudes underpin attributions of , distinguishing human cognition from rote mechanical processes. Mental states also exhibit privileged access, referring to their accessibility, where first-person provides privileged, non-inferential unavailable to third parties through public . Michael Pauen argues in his paper "How Privileged Is First-Person Privileged Access?" that this stems from the immediacy of mental , allowing subjects to know their own beliefs or pains without external , in to the indirect inferences others must rely on. This underscores a core asymmetry in mental phenomena, protecting subjective inner life from complete interpersonal transparency. Additionally, mental phenomena are inherently normative, governed by rational standards like logical or truth-seeking, which differ from the descriptive of machines. Uriah Kriegel explores this in his paper "Intentionality and ," drawing on ' framework to show how intentional states commit agents to norms of correctness (e.g., a must aim at truth), embedding the in a "space of reasons" absent in non-rational systems. Machines may simulate rule-following but lack genuine normative grip, as their operations are causally determined without accountability to justification. These distinctions—intentionality, qualia, propositional attitudes, privileged access, and —collectively enable the philosophical divide between first-person and third-person perspectives on the mind. delineates this in his book , noting that the first-person view captures subjective, experiential immediacy (e.g., "what it is like" to have a thought), while the third-person view treats mental states as observable, objective facts amenable to scientific scrutiny. This duality highlights how mental phenomena bridge inner subjectivity with external reality, posing enduring challenges for unified accounts of the mind.

Theoretical Frameworks

Dualism and Idealism

Substance , as articulated by , posits the mind as a distinct immaterial substance separate from the physical body. In his , Descartes argues that the mind's essence is thinking, which is indivisible and non-extended, in contrast to the body's extended, divisible nature, thereby establishing their ontological separation. He further supports this through the argument from doubt: while sensory perceptions can be deceived, the act of doubting itself proves the existence of a thinking mind (), which cannot be doubted without affirming its reality. Descartes proposed that mind and body interact causally at the in the , where animal spirits facilitate the union and communication between the two substances. Property dualism extends this separation by allowing the mind's to be physical while insisting that mental properties, such as or phenomenal , are irreducible to physical properties. defends this view through the zombie argument, conceiving of beings physically identical to humans but lacking , which demonstrates that is not entailed by physical facts alone. In his framework, even if the brain is material, properties like the experience of pain cannot be fully explained by physical processes, supporting the irreducibility of the mental. Panpsychism represents a contemporary non-physicalist framework that posits or mentality as a fundamental and ubiquitous feature of the physical world, rather than emergent or immaterial. Analytic , revived since the 1970s by thinkers like and further developed by Galen Strawson and Philip Goff, argues that basic particles possess proto-conscious properties, which combine to form complex minds, addressing the hard problem without dualism's interaction issues. However, it faces the "combination problem" of explaining how micro-experiences constitute macro-. Variants include constitutive , where mentality is inherent in physics, and cosmopsychism, positing a consciousness from which individual minds derive. Idealism inverts materialist assumptions by asserting that mind or constitutes the fundamental , with the physical world dependent on . George Berkeley's , outlined in A Treatise Concerning the Principles of Human Knowledge, embodies this through the principle esse est percipi ("to be is to be perceived"), arguing that objects exist only as ideas in perceiving minds and denying independent material substance. Berkeley resolves potential by invoking as the eternal perceiver who sustains the continuity of unperceived objects. A variant, , developed by G.W.F. Hegel, views as the unfolding of absolute spirit through dialectical processes, where individual minds contribute to the of the universal mind in and logic. Historical critiques of highlight the interaction problem: how an immaterial mind can causally influence a material body without violating conservation laws. In her 1643 correspondence with Descartes, Princess Elisabeth of Bohemia challenged this by questioning how a non-extended thinking substance could move extended parts of the body, pressing Descartes to clarify the union of mind and body. Descartes responded by analogizing the mind's influence to gravity's , but Elisabeth's objections underscored the explanatory difficulties of causal interaction between disparate substances. Modern echoes of these non-physicalist views appear in certain quantum interpretations that invoke . The von Neumann-Wigner interpretation posits that conscious causes the of the quantum , suggesting mind plays an irreducible role in physical reality's actualization. formalized this in his mathematical , placing at the end of the chain to resolve indeterminacy, while later emphasized its necessity for explaining quantum outcomes beyond deterministic evolution.

Materialism and Physicalism

Materialism and in the assert that mental phenomena are entirely reducible to or supervenient upon physical processes, particularly those occurring in the , rejecting any non-physical substances or properties. These views emerged as responses to , emphasizing scientific and the explanatory power of physics and . Reductive , a core variant, posits that mental states are identical to physical states, specifically states, as articulated in the mind- identity theory. This theory holds that sensations and other conscious experiences are not distinct from neural processes but are one and the same. The identity theory was pioneered by U.T. Place in his 1956 paper "Is a Process?", where he argued that constitutes a specific type of activity, treatable as a scientific amenable to empirical verification rather than a logical . Place suggested that the apparent gap between phenomenal experience and physical description arises from linguistic and conceptual confusions, proposing that statements about sensations can be translated into neurophysiological terms. Building on this, J.J.C. Smart's 1959 article "Sensations and Processes" advanced a type-identity version, claiming that every type of corresponds to a specific type of state, such as C-fibers firing for . Smart defended this by invoking topic-neutral translations, where mental reports are rephrased as hypothetical statements about events, avoiding direct reference to . Eliminative materialism takes reduction further by arguing that common-sense folk psychology—concepts like beliefs, desires, and intentions—forms a false theory that will be supplanted by mature , much like outdated notions in earlier sciences. , a leading proponent, outlined this in his 1981 paper "Eliminative Materialism and the Propositional Attitudes," contending that propositional attitudes lack neuroscientific correlates and predict behavior poorly, warranting their elimination in favor of vector coding and connectionist models in the brain. Churchland emphasized that folk psychology's stagnation contrasts with rapid advances in , predicting its eventual discard without loss, as caloric or phlogiston theories were abandoned. Physicalism, a broader ontological claim, asserts that everything in the universe is physical or supervenes on the physical, with token-identity theory accommodating . Token physicalism maintains that every particular is identical to some particular physical event, allowing the same (e.g., ) to be realized by different physical substrates across or systems, thus avoiding strict type-identity's anthropocentric limitations. This variant, implicit in Donald Davidson's 1970 , reconciles mental causation with physical laws by token-identifying events while denying strict psychophysical laws due to the anomalism of mental descriptions. Key arguments for these positions include the of the physical domain, which states that every physical event has a sufficient physical cause, leaving no room for non-physical mental causes without or . formalized this in works like his paper "The Myth of Nonreductive Materialism," arguing that violations of would undermine physics' , compelling mental events to be physical to preserve causal . Additionally, favors physicalist explanations by preferring simpler ontologies that do not posit extraneous non-physical entities, as noted in defending identity theory against dualism's added complexities. Historically, these views trace to 19th-century , which, through Auguste Comte's emphasis on phenomena and scientific laws, laid groundwork for rejecting metaphysical speculation about the mind in favor of empirical study. This evolved into 20th-century , which bridged to by focusing solely on as the proper subject of , eschewing . John B. Watson's 1913 manifesto "Psychology as the Behaviorist Views It" declared an objective of prediction and control, dismissing mental states as unscientific. B.F. Skinner extended this in , as in his 1953 book Science and Human , analyzing through and environmental contingencies, paving the way for neuroscientific reductions of mental processes.

Functionalism and Emergentism

in the posits that mental states are defined not by their intrinsic physical composition but by their functional roles, specifically the causal relations they bear to sensory inputs, behavioral outputs, and other mental states. This approach, pioneered by in his 1967 paper "The Nature of Mental States," treats the mind as a of states analogous to computational processes, where, for example, is identified as a functional state involving stimulation from , tendencies to cry out, and desires to avoid further harm. further elaborated this in his 1978 entry "What Is ?," distinguishing it as a metaphysical that allows mental states to be realized in diverse physical substrates, such as biological brains or silicon-based computers, emphasizing over type-identity with specific neural structures. Machine functionalism extends this framework to artificial systems, suggesting that if a device performs the appropriate input-output functions, it possesses the corresponding mental states, with implications for the Turing test as a criterion for intelligence. Alan Turing's 1950 proposal in "Computing Machinery and Intelligence" framed machine intelligence in terms of behavioral indistinguishability from humans, aligning with functionalist criteria by focusing on observable performance rather than internal mechanisms. However, John Searle's 1980 Chinese Room argument critiques this view, illustrating a scenario where a person following syntactic rules manipulates Chinese symbols to pass a Turing test without understanding the semantics, thereby challenging the sufficiency of functional roles for genuine mentality and highlighting the syntax-semantics distinction. Contemporary debates, particularly surrounding large language models as of 2024, question whether purely computational functionalism captures embodied and situated cognition, with embodied cognition theories arguing that mentality requires environmental interaction beyond abstract symbol manipulation. Emergentism complements by proposing that mental properties arise from complex physical interactions but are not reducible to them, exhibiting novel characteristics that supervene on the physical base. Early British emergentists, such as Samuel Alexander in his 1920 work Space, Time, and Deity, argued that mind emerges as a higher-order quality from material processes in an evolutionary hierarchy, where each level introduces unpredictable qualities irreducible to lower ones. In contemporary terms, weak , as analyzed by in his 2006 paper "Strong and Weak Emergence," describes mental phenomena as dependent on physical systems yet unpredictable from complete knowledge of parts due to , as seen in models of neural networks. Strong emergence, in contrast, posits that higher-level properties exert genuine causal influence, including downward causation, where mental states affect physical processes without violating fundamental physical laws. Jaegwon Kim's 1992 analysis in ""Downward Causation" in Emergentism and Nonreductive Physicalism" debates this, questioning whether such causation leads to overdetermination but acknowledging its role in nonreductive accounts where emergent wholes constrain part behaviors. Weak emergentism avoids strong downward causation by treating mental influences as higher-level descriptions of physical interactions, maintaining compatibility with physicalist foundations. Applications of these theories to include Giulio Tononi's , which quantifies via the measure Φ, representing the irreducible causal power of a system's integrated , emerging from neural complexity without reducing to individual neuron firings.

Mind-Body Relations

The Mind-Body Problem

The mind-body problem concerns the fundamental relationship between mental phenomena, such as thoughts, sensations, and , and physical processes in the body, particularly the . This issue arises from the apparent ontological distinction between the immaterial nature of the mind and the material nature of the body, questioning how, if at all, they interact or relate. Historically, formulated the problem in the through his substance , positing that mind and body are distinct substances—res cogitans (thinking substance) and res extensa (extended substance)—that causally interact, with the mind influencing the body via the . ' thus established the core challenge of explaining this causal interplay without violating the conservation of physical laws. In response to interactionist difficulties, alternative variants emerged. Thomas Huxley introduced in the , viewing mental states as byproducts of physical processes that lack causal efficacy on the , akin to steam whistles on a that signal but do not drive the engine. proposed parallelism through his doctrine of pre-established , where mind and do not interact but run in perfect synchrony, as if two clocks set by God to tick together eternally. Similarly, Nicolas Malebranche's occasionalism maintained that no direct causal interaction occurs between mind and ; instead, God intervenes on every occasion to produce correlated effects, ensuring without genuine mind-body causation. In modern philosophy, restated the mind-body problem in 1995 by distinguishing the —explaining why physical processes give rise to subjective experience ()—from the "easy problems" of accounting for cognitive functions like or memory through scientific explanation. Arguments for the irreducibility of mental states to physical facts include Frank Jackson's 1982 , illustrated by "Mary's room": a scientist who knows all physical facts about color but, confined to a environment, learns something new upon seeing for the first time, implying beyond physical description. Addressing causal issues, Donald Davidson's (1970) posits that mental events are identical to physical events yet lack strict psychophysical laws, allowing mental causation through token identity while preserving the nomological character of physical sciences.

Neural Correlates and Brain Processes

The (NCC) refer to the minimal set of neuronal events and mechanisms sufficient for a specific conscious percept. Pioneering work by and proposed that NCC could be identified through phenomena like binocular rivalry, where conflicting images presented to each eye alternate in despite constant stimulation, allowing dissociation of stimulus from . Their research highlighted 40 Hz gamma oscillations in the as potential correlates of visual , synchronizing activity across regions during conscious but not during unconscious processing. These oscillations facilitate binding of sensory features into unified percepts, as evidenced in studies using (MEG) to track rivalry-induced shifts. Specific brain networks underpin various mental states. The (DMN), comprising regions like the medial and posterior cingulate, activates during and self-referential thought, deactivating during externally focused tasks. This network supports internal mentation, such as retrieval, with hyperactivity linked to spontaneous rumination. In contrast, thalamocortical loops, involving reciprocal connections between the and , regulate and , modulating through rhythmic bursting in low- states and tonic firing during heightened vigilance. These loops integrate sensory inputs to sustain conscious states, with disruptions impairing overall . Key brain processes link neural activity to mental functions via and . Hebbian learning, encapsulated in the principle "cells that fire together wire together," describes how correlated pre- and postsynaptic activity strengthens synaptic connections, enabling experience-dependent modifications underlying formation. This mechanism, formalized in Donald Hebb's 1949 theory, relies on (LTP) in hippocampal circuits. Neurotransmitters like further shape mental states by signaling reward prediction errors; neurons phasically respond to unexpected rewards, reinforcing learning and in the and . Non-invasive imaging techniques reveal these correlates by mapping activity to mental tasks. (fMRI) measures blood-oxygen-level-dependent (BOLD) signals, which increase in regions engaged by cognitive demands, such as prefrontal activation during . BOLD responses correlate with local neural firing and metabolism, providing spatial resolution for task-evoked mental processes like . (EEG), with its high temporal precision, captures millisecond-scale dynamics, such as event-related potentials (ERPs) reflecting perceptual awareness or alpha-band desynchronization during focused . Recent advances in have established causal roles for specific circuits in mental states using animal models. In 2025 studies, optogenetic activation of distinct hypothalamic populations, such as VMHdmSF1 cells, elicited predator-imminence responses in mice, including freezing and avoidance, demonstrating direct manipulation of affective states. These findings extend NCC research by proving that targeted neural interventions can control conscious experiences like .

Development of the Mind

Evolutionary Origins

The evolutionary origins of the mind are rooted in proto-mental capacities observed in simple organisms, where basic reflexive behaviors served adaptive functions for survival. In single-celled organisms like the protist Paramecium, reflexive responses to environmental stimuli, such as avoiding obstacles or seeking nutrients, demonstrate early forms of non-neural information processing and associative learning, predating multicellular nervous systems by billions of years. These proto-mental traits evolved into more integrated sensory-motor coordination in invertebrates during the Cambrian explosion around 540 million years ago, as seen in cnidarians like jellyfish, which use nerve nets for directed swimming and prey capture, and in annelid worms exhibiting habituation and classical conditioning to optimize foraging and predator avoidance. Such mechanisms laid the phylogenetic foundation for mental phenomena by enabling selective environmental responsiveness without centralized brains. In vertebrates, pivotal milestones marked the transition to more sophisticated mental faculties. Reptiles and amphibians, emerging around 350 million years ago, developed structures homologous to the mammalian , including the , which underpin basic emotional processing for instinctual behaviors like territorial defense and reproduction, enhancing in variable environments. The full , incorporating the and for and , crystallized in early mammals approximately 200 million years ago, allowing for affective learning that integrated sensory inputs with motivational states to support nurturing and social bonding. Concurrently, the arose as a mammalian from a thin dorsal cortex, initially small and sensory-focused in early mammals but expanding dramatically in to facilitate advanced , such as and , through layered neural architectures that process multimodal information. Human-specific advancements in mental evolution occurred within the hominin , diverging from other 6-7 million years ago. The gene, a regulating vocal and neural plasticity, underwent two substitutions in the , fixed at least 400,000 years ago in the common of modern humans and Neanderthals, contributing to fine-tuned orofacial movements essential for articulate speech and . Mirror neurons, first identified by Rizzolatti and colleagues in the of macaques, are present in and thought to have contributed to the development of in hominins, enabling the simulation of observed actions and intentions that facilitated cooperative hunting and communication in expanding social groups. Evolutionary theories emphasize the adaptive sculpting of mental architecture for survival challenges. Tooby and Cosmides' massive modularity hypothesis proposes that the mind comprises numerous domain-specific modules, each honed by for recurrent ancestral problems, such as a cheater detection module that enhances reciprocity in social exchanges by intuitively identifying violations of norms, as demonstrated in experimental tasks mimicking evolutionary dilemmas. This modular framework explains how mental traits confer advantages, from predator evasion to alliance formation, across phylogenetic scales. Fossil records provide tangible evidence of mental evolution through encephalization in hominins. Brain volume increased from approximately 600 cm³ in Homo habilis (circa 2.3 million years ago), associated with rudimentary Oldowan stone tools for scavenging and basic group coordination, to about 1,400 cm³ in Homo sapiens (emerging 300,000 years ago), correlating with sophisticated Acheulean and later technologies, symbolic art, and complex social structures supporting larger, kin-based networks up to 150 individuals. This tripling of brain size over 2 million years reflects selection pressures for enhanced problem-solving and social intelligence, driving the uniquely human mind.

Individual Development

The development of the mind begins prenatally, with foundational neural structures emerging early in . By the third and fourth weeks of embryonic development, the forms through primary , starting as an open that folds and closes to establish the precursor of the , including the and . , a process that refines neural connections by eliminating excess synapses to enhance efficiency, also initiates , contributing to the organization of the fetal even before birth. In infancy, key cognitive and emotional milestones mark the initial maturation of mental faculties during Piaget's sensorimotor stage, which spans from birth to about 18-24 months. A pivotal achievement is the development of around 8-12 months, where infants grasp that objects continue to exist even when out of sight, as demonstrated through tasks involving hidden toys; this concept, central to Piaget's theory, reflects the transition from reflexive actions to intentional mental representations. Basic emotions such as , distress, interest, and emerge reliably by 6 months, enabling infants to express and respond to , which supports early bonding and environmental interaction. During childhood, more advanced mental processes solidify, including the acquisition of —the ability to attribute mental states to oneself and others—typically around age 4. This is evidenced by success in false belief tasks, such as those developed by Wimmer and Perner, where children predict behavior based on another's mistaken belief about an object's location, indicating an understanding that mental representations can differ from reality. Concurrently, like , , and grow through the maturation of the , which undergoes progressive myelination and synaptic refinement from onward, allowing children to plan, focus, and adapt behaviors more effectively. In and early adulthood, synaptic refinement continues, with peak pruning and reorganization of prefrontal connections occurring around age 25, as longitudinal MRI studies reveal a wave of reduction that streamlines neural circuits for complex and impulse regulation. persists throughout adulthood, facilitating by enabling structural changes such as dendritic growth and synaptic strengthening in response to experiences, which sustains cognitive adaptability beyond developmental peaks. Environmental influences play a crucial role in shaping mental development across stages, interacting with biological timelines. Critical periods, such as the window for native-like extending from early infancy to , underscore the brain's heightened sensitivity to linguistic input during this phase, as proposed by Lenneberg based on parallels between cerebral lateralization and skill attainment. formed through consistent caregiver responsiveness, as outlined in Bowlby's theory, further molds emotional regulation and by providing a stable base for exploring mental models of relationships.

Minds Beyond Humans

Animal Cognition and Consciousness

Animal encompasses a range of mental processes observed in non-human species, including problem-solving, memory, and social reasoning, which suggest the presence of sophisticated minds. New Caledonian crows (Corvus moneduloides) demonstrate advanced tool use by manufacturing hooked sticks from twigs or leaves to extract food from crevices, a behavior that requires planning and causal understanding. This skill, documented in wild populations, highlights corvids' capacity for innovation beyond simple . Similarly, great apes exhibit self-recognition, as evidenced by the developed by Gordon Gallup, where chimpanzees marked with odorless dye on their faces use the reflection to touch the mark, indicating awareness of self. Such abilities in and challenge traditional views of as uniquely . Comparative psychology has further illuminated animal minds through controlled experiments on communication and quantification. In the 1960s, R. Allen Gardner and Beatrix T. Gardner raised the Washoe in a human-like , teaching her over 150 signs from , which she combined creatively to express novel ideas, such as naming a "water bird." This suggests rudimentary linguistic competence, though debates persist on whether it constitutes true . Pigeons (Columba livia) also display numerical competence comparable to , accurately ordering visual arrays by and learning abstract rules like "same/different" across numerosities up to 9 items. These findings indicate that basic arithmetic-like processing is widespread among vertebrates. Indicators of consciousness in animals include behavioral and neurophysiological responses to subjective experiences, such as and . The 2012 Cambridge Declaration on Consciousness, signed by leading neuroscientists at the Memorial Conference, asserts that non-human animals, including all mammals and , possess the neurological substrates of , and many other organisms like octopuses also exhibit intentional behaviors. In cephalopods, octopuses show affective responses, avoiding locations associated with injury, displaying location-specific grooming after noxious injections, and altering in ways indicative of emotional distress rather than mere . These observations support the view that arises from convergent evolutionary pressures across diverse taxa. Neural homologies provide a biological basis for these cognitive parallels. In birds, the nidopallium caudolaterale serves functions akin to the mammalian , supporting executive control, , and , despite lacking a laminated . Mammalian homologs to human association areas, such as the prefrontal regions involved in higher , are evident in and cetaceans, underscoring shared neural architectures for complex mental states. Debates in ethology balance the risk of anthropomorphism—attributing human-like emotions without evidence—against C. Lloyd Morgan's canon, which urges interpreting animal behavior with the simplest psychological explanation possible. Morgan's 1894 principle promotes caution but has been critiqued for potentially underestimating animal minds. Recent ethology research, including 2025 studies on self-directed behaviors in captive Asian elephants reflecting social stress and empathy, reinforces evidence for emotional contagion and consolation in elephants, where individuals comfort distressed conspecifics through tactile reassurance. These updates highlight elephants' empathic responses, such as investigating and aiding injured group members, aligning with broader patterns of social cognition.

Artificial Intelligence and Synthetic Minds

Artificial intelligence (AI) has sought to replicate aspects of the human mind through computational systems, beginning with classical approaches that emphasized symbolic manipulation. In the mid-20th century, researchers developed Good Old-Fashioned AI (GOFAI), which modeled intelligence using explicit rules and logical representations to mimic human reasoning. A seminal example is the General Problem Solver (GPS), created by Allen Newell, J.C. Shaw, and in 1959, which employed means-ends analysis to break down complex problems into subgoals, demonstrating early successes in tasks like theorem proving and puzzle solving. This symbolic paradigm, as articulated by philosopher John Haugeland in his 1985 analysis, treated the mind as a of representations and rules, aiming for general intelligence through hierarchical planning and search algorithms. Shifting from rigid symbolism, emerged in the 1980s as an alternative framework inspired by neural structures, positing that intelligence arises from interconnected networks processing information in parallel. David E. Rumelhart and James L. McClelland's two-volume work, Parallel Distributed Processing (1986), formalized this approach, describing how simple units linked by weighted connections could learn patterns through distributed representations, enabling robust handling of ambiguity and generalization. A key enabler was the algorithm, introduced by Rumelhart, Geoffrey E. Hinton, and Ronald J. Williams in 1986, which allowed multilayer networks to adjust weights by propagating errors backward from output to input layers, facilitating training on diverse datasets for tasks like . Unlike GOFAI's top-down logic, connectionist models emphasized bottom-up , aligning with functionalist ideas of where mind-like functions could be substrate-independent. Debates on whether AI can achieve true consciousness—often termed , implying genuine understanding—have centered on philosophical critiques of syntactic processing. John Searle's 1980 argument posits that a system manipulating symbols according to rules, like a person following instructions to respond in Chinese without comprehension, lacks semantic understanding, distinguishing it from weak AI as mere . In response, (IIT), developed by since 2004 and refined in 2014, proposes measuring consciousness via Φ, the quantity of irreducible, integrated information generated by a system's causal interactions; applications to AI suggest that certain architectures could theoretically yield high Φ values, though current models fall short of biological levels. These discussions highlight ongoing tensions between behavioral mimicry and intrinsic mental states in synthetic systems. By 2025, large language models (LLMs) represent a pinnacle of connectionist evolution, with successors to like OpenAI's GPT-5, released on August 7, 2025, exhibiting scaled-up capabilities in and reasoning. Trained on vast multimodal datasets, these models demonstrate emergent behaviors, such as proxy — inferring mental states from context in social scenarios—emerging at parameter scales beyond 100 billion. A 2025 mechanistic analysis reveals that LLMs encode theory-of-mind representations through sparse, attention-related parameters, though debates persist on whether this constitutes genuine understanding or statistical pattern matching. Ethical considerations in synthetic minds have prompted discussions on for advanced entities, exemplified by the 2017 granting of to , a developed by , by —the first instance of legal for a non-biological entity. This symbolic act, intended to promote innovation, sparked global debates on robot , including obligations for ethical treatment and potential in decision-making, influencing frameworks like the UN's discussions on governance. Such developments underscore the need for policies addressing accountability in systems that simulate mind-like traits, balancing technological progress with societal implications.

Mental Health and Pathology

Normal Mental Functioning

Normal mental functioning encompasses the adaptive cognitive and emotional processes that enable healthy individuals to navigate daily life effectively. Cognitive equilibrium refers to the balanced allocation of attentional resources, allowing individuals to focus on relevant stimuli while filtering distractions, which supports efficient information processing in routine tasks. This balance is achieved through flexible attentional networks that prioritize goal-directed activities, as demonstrated in studies of regulation in healthy adults. , a key component of this equilibrium, occurs predominantly during , with rapid eye movement () cycles playing a critical role in stabilizing declarative and procedural memories by reactivating neural traces formed during wakefulness. Problem-solving in normal functioning often relies on heuristics, as outlined in Kahneman's dual-process model, where provides intuitive, rapid judgments through and availability biases, while engages deliberate, for more complex challenges. Emotional aspects of normal mental functioning involve adaptive regulation that promotes and . Positive psychology, pioneered by Seligman, emphasizes states—periods of deep immersion in activities where challenges match skills, leading to heightened and intrinsic motivation—as central to emotional flourishing. , another key element, is fostered through Seligman's PERMA model, which integrates positive , , relationships, meaning, and accomplishment to buffer against stressors and sustain psychological health. This emotional regulation is supported by mechanisms, particularly parasympathetic activity, which modulates physiological responses to maintain during emotional experiences and prevent dysregulation. Social functioning in healthy individuals includes and interpersonal inference, enabling accurate interpretation of others' mental states to facilitate cooperation and conflict resolution. This capacity is underpinned by the social brain hypothesis, which posits that human evolution supports stable social groups of approximately 150 members, allowing for meaningful relationships within cognitive limits. Metrics of normality often reference intelligence quotients (IQ) from standardized tests like the , which follow a with a mean of 100 and standard deviation of 15, encompassing about 68% of the population between 85 and 115. However, this unidimensional measure is critiqued in favor of Gardner's , which identifies distinct domains such as linguistic, logical-mathematical, and interpersonal intelligences, providing a more holistic view of adaptive mental capabilities. Daily integration of mental functioning is influenced by circadian rhythms, which synchronize alertness and cognitive performance with the 24-hour cycle, typically peaking in the late morning to early afternoon for most individuals. Recent research highlights that aligning tasks with personal chronotypes—morning or evening preferences—optimizes mental peaks, with misalignment leading to reduced efficiency in and .

Psychological Disorders and Impairments

Psychological disorders represent significant impairments in mental processes, disrupting , regulation, and functioning in ways that deviate markedly from typical mental states. These conditions often involve persistent alterations in , thought patterns, or , leading to substantial distress or impaired daily activities. Major categories include mood disorders, anxiety disorders, neurodevelopmental disorders, and psychotic disorders, each characterized by specific symptom profiles outlined in the DSM-5-TR. Mood disorders, such as major depressive disorder (MDD) and bipolar disorder, profoundly affect emotional stability and motivation. In MDD, individuals experience at least five symptoms during a two-week period, including depressed mood or markedly diminished interest or pleasure in activities, along with changes in appetite or weight, sleep disturbances, psychomotor agitation or retardation, fatigue, feelings of worthlessness or excessive guilt, diminished ability to think or concentrate, and recurrent thoughts of death or suicidal ideation. These symptoms cause clinically significant distress or impairment, contrasting with normal mood fluctuations by their intensity and duration. Bipolar disorder involves at least one manic episode for bipolar I, characterized by a distinct period of abnormally elevated, expansive, or irritable mood and increased energy lasting at least one week (or any duration if hospitalization is required), accompanied by symptoms like grandiosity, decreased need for sleep, talkativeness, flight of ideas, distractibility, increased goal-directed activity, or excessive involvement in risky behaviors. Bipolar II requires at least one hypomanic episode (similar but less severe, lasting four days) and one major depressive episode, highlighting cycles of extreme highs and lows that impair judgment and functioning far beyond typical emotional variability. Anxiety disorders manifest as excessive fear or worry that interferes with mental clarity and adaptive responses, differing from normal apprehension by their pervasiveness and resistance to reassurance. (GAD) involves excessive anxiety and worry occurring more days than not for at least six months, about various events or activities, accompanied by symptoms such as restlessness, , difficulty concentrating, irritability, muscle tension, and disturbance. The lifetime prevalence of GAD among U.S. adults is approximately 5.7%, underscoring its commonality as a impairment in sustained and emotional control. In contrast, (PTSD) arises after exposure to actual or threatened death, serious injury, or , featuring intrusion symptoms like recurrent distressing memories, nightmares, or intense psychological distress at exposure to reminders, including flashbacks where the individual feels or acts as if the traumatic event were recurring. PTSD also includes persistent avoidance of trauma-related stimuli, negative alterations in cognitions and mood (e.g., inability to experience positive emotions), and marked alterations in arousal and reactivity (e.g., , exaggerated ), lasting more than one month and causing significant functional impairment. Neurodevelopmental disorders emerge early in life and involve deficits in maturation that affect social, communicative, and behavioral regulation, setting them apart from acquired s in adulthood. is defined by persistent deficits in social communication and social interaction across multiple contexts, such as deficits in social-emotional reciprocity, nonverbal communicative behaviors, and developing or maintaining relationships, alongside restricted, repetitive patterns of behavior, interests, or activities, including stereotyped or repetitive motor movements, insistence on sameness, highly restricted interests, or hyper- or hyporeactivity to sensory input. Symptoms must be present in early developmental period, even if not fully manifest until social demands exceed limited capacities, and cause clinically significant . Attention-deficit/hyperactivity disorder (ADHD) requires at least six symptoms (five for adolescents and adults) of inattention (e.g., failure to give close attention to details, difficulty sustaining attention, not following through on instructions) and/or hyperactivity-impulsivity (e.g., , leaving seat when remaining seated is expected, excessive talking, interrupting others) for children, or five for those over 17, persisting for at least six months to a degree inconsistent with developmental level and interfering with functioning in multiple settings. These symptoms must onset before age 12, distinguishing ADHD from situational inattention in typical development. Psychotic disorders, exemplified by , entail profound disruptions in testing and thought organization, far exceeding normal perceptual variations. is characterized by positive symptoms such as delusions (fixed false beliefs, e.g., persecutory or grandiose), hallucinations (often auditory), disorganized thinking (e.g., loose associations), and grossly disorganized or abnormal motor behavior (e.g., catatonia), alongside negative symptoms like diminished emotional expression (flat affect), (lack of motivation), (poverty of speech), (inability to feel pleasure), and . At least two of these symptoms (one must be delusions, hallucinations, or disorganized speech) must be present for a significant portion of one month, with continuous signs for at least six months, leading to marked social or occupational dysfunction. The hypothesis posits that involves hyperactivity in mesolimbic pathways, contributing to positive symptoms, and hypoactivity in mesocortical pathways, linked to negative symptoms and cognitive deficits. As of 2025, Compass Pathways' phase 3 trial (COMP005) for -assisted interventions in successfully met its primary endpoint in June 2025, building on phase 2 trials showing rapid and sustained symptom reduction in (MDD) and (TRD) populations involving over 500 participants across multiple studies. The U.S. granted designation for in 2018. This single-dose treatment demonstrated significant and sustained alleviation of depressive symptoms compared to up to 12 weeks, without traditional mechanisms. These developments underscore evolving understandings of mind-altering substances in addressing refractory mood impairments.

Fields of Inquiry

Psychological Approaches

Psychological approaches to studying the mind emphasize observable behaviors, internal mental processes, and therapeutic interventions, drawing on experimental methods and clinical observations to understand , , and . These disciplines prioritize from controlled studies and self-reports, focusing on how individuals perceive, learn, and adapt to their environments through behavioral patterns and cognitive frameworks. Behavioral psychology, pioneered by and , centers on conditioning as a mechanism for learning and mental functioning. Pavlov's demonstrated how neutral stimuli, such as a bell, could elicit reflexive responses like salivation when paired with unconditioned stimuli like food, establishing foundational principles for associative learning in the mind. Skinner extended this to , showing that behaviors are shaped by reinforcements and punishments, as detailed in his 1938 work where voluntary actions increase or decrease based on consequences in controlled environments like the Skinner box. These principles underpin applied therapies, including (CBT) developed by , which targets maladaptive thought patterns through behavioral techniques to restructure cognitive distortions and alleviate psychological distress. Cognitive psychology examines internal mental representations, such as schemas and models, to explain how the mind processes information. Jean Piaget's theory of and describes how children integrate new experiences into existing cognitive structures () or modify those structures to fit novel information (), facilitating adaptive mental development across stages. Experimental paradigms like the Stroop test, introduced by John Ridley Stroop in 1935, reveal cognitive interference, where automatic reading processes conflict with color-naming tasks, slowing response times and highlighting the mind's selective attention mechanisms. Humanistic approaches shift focus to subjective experience and personal growth, viewing the mind as inherently oriented toward . Abraham Maslow's , outlined in his 1943 paper, posits a of motivations from physiological and safety needs at the base to esteem and at the apex, arguing that fulfillment of lower needs enables higher psychological integration. Carl ' person-centered therapy, elaborated in his 1951 book, emphasizes , , and congruence to foster clients' innate capacity for self-understanding and actualization, promoting through non-directive dialogue. Developmental psychology explores how social interactions shape mental growth, particularly through Lev Vygotsky's concept of the (ZPD), which defines the gap between independent performance and potential achievement with guidance from more knowledgeable others, as synthesized in his 1978 collection of works. This sociocultural framework underscores as key to internalizing cognitive tools and advancing mental capabilities. Quantitative methods in , such as , provide rigorous tools for assessing mental constructs through standardized tests. The (MMPI), developed in 1943, exemplifies this by measuring traits and with scales demonstrating high reliability (test-retest coefficients often exceeding 0.80) and validity (correlations with clinical diagnoses around 0.70-0.90), ensuring dependable inference about mental states.

Neuroscientific Methods

Neuroscientific methods encompass a range of techniques that probe the biological underpinnings of the by visualizing, recording, or manipulating structure and activity. These approaches provide empirical insights into neural mechanisms supporting , , and , often revealing correlates of mental processes such as and . Structural imaging techniques, such as (MRI), enable high-resolution mapping of anatomy without , allowing researchers to delineate cortical and subcortical regions implicated in mental functions. MRI has been instrumental in studying neuroanatomical variations across individuals and populations, facilitating the identification of structural bases for cognitive traits. Diffusion tensor imaging (DTI), an extension of MRI, quantifies the diffusion of water molecules to infer the integrity and orientation of tracts, which form the connective networks linking distributed areas involved in mental processing. For instance, DTI reveals disruptions in tracts like the in conditions affecting interhemispheric communication, highlighting their role in integrated mental operations. Functional imaging methods track dynamic activity during mental tasks. Positron emission tomography () measures regional glucose metabolism as a proxy for neural energy demands, showing increased uptake in task-relevant areas such as the during executive function challenges. This technique, using tracers like 18F-fluorodeoxyglucose, provides quantitative insights into metabolic correlates of mental effort. Functional MRI (fMRI), based on blood-oxygen-level-dependent (BOLD) signals, captures hemodynamic responses—changes in blood flow and oxygenation following neural activation—to localize active regions with millimeter and seconds-long temporal . Seminal work demonstrated that these responses reliably index neuronal firing patterns during cognitive tasks, enabling the study of mental states like and . Electrophysiological methods offer direct measures of neural electrical activity. Single-cell recording, typically performed in animal models, involves microelectrodes to capture action potentials from individual neurons, revealing how specific cells encode mental representations such as spatial in the . This invasive approach in behaving animals has elucidated the fine-grained dynamics of neural circuits underlying . Non-invasively, () detects the weak magnetic fields generated by synchronized neuronal currents, providing millisecond temporal resolution for tracking rapid mental processes like without interference from skull or scalp. has been pivotal in mapping oscillatory patterns associated with and . Invasive techniques allow precise manipulation of neural activity to test causal roles in mental functions. (DBS) delivers electrical pulses via implanted electrodes to modulate dysfunctional circuits in disorders like , alleviating symptoms such as motor rigidity and cognitive inflexibility by normalizing pathological oscillations in networks. , pioneered in 2005, uses light-sensitive proteins (opsins) expressed in targeted neurons via to control their firing with millisecond precision, enabling dissection of cell-type-specific contributions to behaviors and mental states in animal models. This has revolutionized in by allowing bidirectional control of excitation and inhibition. As of 2025, innovations in brain-computer interfaces (BCIs) represent a frontier for direct readout and interaction with mental activity. Neuralink's N1 Implant, tested in human clinical trials for individuals with quadriplegia, decodes neural signals to enable thought-controlled cursor movement and operation, achieving high-bandwidth communication between and . These trials demonstrate the potential for BCIs to restore agency in impaired mental-motor functions, with ongoing feasibility studies expanding to assistive .

Philosophical Investigations

Philosophical investigations into the mind encompass key and metaphysical questions, probing the nature of about mental states and the boundaries of itself. In , the concept of privileged access posits that individuals have a superior epistemic position regarding their own mental states through , which is often regarded as more reliable than external observation for accessing one's thoughts and experiences. This view traces to classical sources but faces challenges concerning the reliability of , as empirical studies and philosophical critiques suggest it may be prone to error or bias, undermining claims of infallibility. Complementing this is the , which questions how one can justify beliefs about the mental states of others, typically relying on from rather than direct access, leading to about or the certainty of intersubjective . Metaphysically, the challenges traditional boundaries of the mind by arguing that cognitive processes can extend beyond the biological brain into the environment, particularly through interactions with tools or artifacts. Proposed by Andy Clark and , this view uses the example of , who relies on a notebook for memory in a manner functionally equivalent to Inga's biological recall, suggesting that such external aids constitute part of the mind if they are reliably coupled and play a constitutive role in . This active externalism implies that the mind is not confined to intracranial processes but distributed across brain-body-world systems, influencing debates on and cognitive enhancement. The intersection of and the mind further complicates metaphysical inquiries, particularly in light of deterministic processes. , as articulated by , reconciles with by redefining it as the capacity for rational and control within a causally determined framework, where agents act in accordance with their motivations without external coercion, even if neural events are predictable. In contrast, asserts the existence of genuine to preserve alternative possibilities for action, rejecting strict compatibility with and emphasizing non-physical or quantum indeterministic elements in decision-making. These positions highlight tensions between philosophical and emerging neuroscientific evidence of predictive activity preceding conscious choices. Phenomenology offers a descriptive approach to the mind's structures, focusing on the of . Edmund Husserl's method of , or , involves suspending judgments about the external world's existence to isolate and describe the pure phenomena of , aiming to uncover invariant essences of mental acts without presuppositions. This technique has profoundly influenced studies of —the subjective, qualitative aspects of experience—by providing a framework for analyzing how presents itself, independent of causal explanations, and fostering inquiries into the irreducibility of phenomenal properties. Contemporary philosophical issues extend these traditions into models of selfhood, such as Thomas Metzinger's simulation theory, which portrays the as a generated by the brain's transparent self-model. In this view, the phenomenal emerges from neural simulations that create an illusory first-person , integrating into a coherent but non-veridical representation, akin to a in a computational . This theory draws on the self-model theory of subjectivity to explain phenomena like out-of-body experiences and challenges naive about the mind, suggesting that is a functional rather than a direct reflection of reality.

Cognitive Science Integrations

Cognitive science integrates multiple disciplines to develop computational and experimental models of the mind, drawing on , , , , and to understand as an information-processing system. Pioneers Allen Newell and Herbert laid foundational groundwork by proposing that the mind operates through symbolic computation, as exemplified in their development of the program, which automated and demonstrated machine intelligence akin to human problem-solving. This interdisciplinary approach, formalized in the 1970s, treats the mind as a "society" of interacting processes, enabling unified theories that bridge behavioral observations with mechanistic simulations. A key method in this integration is computational modeling, particularly through cognitive architectures like , developed by John R. Anderson, which simulates human by combining (facts stored in chunks) with procedural rules (productions) to model retrieval, learning, and . posits that emerges from a where activation levels in determine the speed and accuracy of information access, allowing predictions of human performance in tasks such as or driving. This architecture has been validated against empirical data from and , providing a unified framework for testing hypotheses across domains. Embodied cognition further enriches these models by emphasizing that mental processes are grounded in the body's interactions with the environment, rather than being abstract computations. George Lakoff and Mark Johnson's theory of conceptual metaphors illustrates this, arguing that abstract thought relies on mappings from sensorimotor experiences—such as "grasping" an idea from physical handling—to structure language and reasoning. For instance, metaphors like "argument is war" derive from bodily confrontations, influencing how cognition shapes and is shaped by physical contexts, integrating insights from linguistics and anthropology. David Marr's levels of analysis provide a structured for this synthesis, delineating three complementary perspectives: the computational level, which specifies the task's goal and input-output mapping (the "what"); the algorithmic level, detailing representations and procedures (the "how"); and the implementational level, addressing physical realization in neural hardware (the "how it works physically"). This hierarchy ensures that models from disparate fields align, for example, by linking psychological algorithms to neuroscientific implementations without reducing one to the other. As of 2025, frontiers in increasingly center on the Bayesian brain hypothesis within predictive processing frameworks, positing that the mind functions as a hierarchical engine that minimizes prediction errors between internal models and sensory data to unify , action, and learning. This approach, advanced by , integrates and by modeling the as generating top-down predictions to anticipate environmental changes, with empirical support from studies showing error signals in cortical hierarchies. Recent reviews highlight its role in explaining adaptive behaviors, such as and belief updating, positioning it as a convergent across disciplines.

Broader Implications

Cultural and Social Dimensions

Conceptions of the exhibit significant , with Western traditions often emphasizing an individualistic, autonomous focused on internal states and rational analysis, while Eastern philosophies promote a holistic view integrating the with broader relational and contextual elements. For instance, in Western analytic , individuals prioritize objects and categories, attributing to inherent properties, which aligns with a decontextualized understanding of mental processes. In contrast, East Asian holistic attends to the entire field, emphasizing relationships and dialectical harmony, shaping a perceived as embedded in social and environmental dynamics. This dichotomy reflects deeper metaphysical differences, where Westerners view the as rule-bound and categorical, whereas Easterners see it as dynamic and context-dependent. A prominent Eastern example is the Hindu concept of in , which posits the individual self as identical to , the universal underlying all reality, transcending personal boundaries to encompass a unified, eternal awareness. The social construction of the mind underscores how cultural tools, particularly , mediate thought and . Lev Vygotsky's sociocultural theory argues that higher mental functions, including thought, emerge through social interactions, with serving as a primary cultural tool that internalizes external speech into verbal thinking. This process transforms the mind from a biologically driven entity into one shaped by communal practices, where tools like enable the through guided interactions. Variants of the Sapir-Whorf hypothesis, known as , further suggest that structures influence cognitive categories and perceptions, such that speakers of different languages conceptualize —and thus the mind's operations—distinctly, though not deterministically. For example, languages with nuanced spatial terms may foster corresponding mental frameworks for navigation and relational thinking. In collectivist cultures influenced by Confucianism, the relational self redefines the mind as interdependent, prioritizing harmony in social networks over isolated autonomy, which impacts empathy and decision-making. The Confucian emphasis on ren (benevolence) and role-based ethics cultivates empathy directed toward in-group relations, enhancing prosocial responses within familial and communal contexts. This relational orientation leads to decision-making that balances individual desires with collective propriety (li), often subordinating personal gain to maintain group equilibrium, as observed in East Asian business practices where moral actions stem from ingrained social roles. Such influences contrast with individualistic frameworks, fostering a mind attuned to contextual obligations rather than abstract rights. Modern media and technology, particularly social platforms, reshape mental processes by fostering addictive behaviors through reward mechanisms. Platforms use elements like likes and unpredictable notifications to create compulsive checking behaviors via variable reinforcement schedules, which can trigger dopamine releases and mimic addictive patterns. Studies indicate that heavy social media use correlates with reduced attention spans, impairing working memory and cognitive control, as constant stimulation disrupts deeper mental engagement. Anthropological perspectives highlight indigenous animism, where minds are attributed to non-human entities like animals, , and landscapes, challenging anthropocentric views that confine mentality to humans. In cultures such as the Ngöbe of , agency is relationally ascribed to non-humans based on communicative and ecological interactions, viewing the world as populated by persons with graded rather than binary human-nonhuman divides. This ecocentric attribution fosters a mind-world , informing sustainable practices and contrasting scientific materialism's exclusion of mentality from non-sentient forms.

Ethical and Legal Considerations

Discussions of in the context of the mind often center on the implications of for assigning blame in ethical judgments. Joshua Greene's dual-process posits that moral decision-making involves an automatic, emotion-driven process that favors deontological intuitions and a slower, deliberative utilitarian process, with the former potentially undermining perceptions of rational agency and thus in cases where emotional biases override deliberate choice. This framework suggests that diminished , as evidenced in studies of moral dilemmas, could reduce blame attribution for actions driven by intuitive rather than controlled , influencing ethical on . In legal systems, assessments of mental capacity play a critical role in determining criminal responsibility, particularly through the and evaluations of competency to stand trial. The , established in following the trial of , define as a defect of reason from a disease of the mind that prevents the accused from knowing the nature and quality of their act or that it was wrong, thereby excusing liability if proven. Complementing this, competency to stand trial requires that defendants understand the proceedings, charges, and consequences, as well as consult with counsel, with U.S. federal law under 18 U.S.C. § 4241 mandating hearings if doubts arise about mental competence. These standards ensure that only those with sufficient mental capacity face full legal accountability, protecting rights. Advancements in , such as brain-computer interfaces (BCIs), raise profound neuroethical concerns regarding and the potential for mind-reading or thought . Neuroethicists argue that BCIs, which decode neural signals to interpret intentions or emotions, could erode mental by enabling unauthorized access to private thoughts, akin to "brainjacking," necessitating safeguards like rights to prevent abuses. As of November 2025, international bodies, including , have adopted standards emphasizing that brain data's intimate nature demands strict confidentiality protections; on November 7, 2025, adopted the first global Recommendation on the Ethics of to uphold against invasive applications. Extending philosophical arguments about to non-human entities, Peter Singer's utilitarian framework in Animal Liberation asserts that moral consideration should extend to all beings capable of , regardless of , challenging human-centric views and advocating protections for animals based on their mental experiences. This principle has inspired analogous debates on rights, where regulations like the EU Act of 2024 classify high-risk systems—including those simulating cognitive processes—as subject to transparency, accountability, and human oversight requirements to mitigate harms from potentially sentient-like technologies. As of 2025, ethical debates on mind enhancement intensify around nootropics and transhumanist visions, questioning the moral permissibility of cognitive boosters like that enhance or in healthy individuals, potentially exacerbating inequalities without clear long-term safety data. Transhumanists advocate for such interventions as pathways to transcending human limitations, yet critics highlight risks of and loss of authenticity in altered mental states. Concurrently, consent issues in mind-altering therapies, particularly psychedelics like , demand nuanced models that account for transformative experiences impairing anticipatory decision-making, with bioethicists calling for ongoing capacity assessments during treatment. These concerns underscore the need for regulatory frameworks balancing therapeutic benefits against violations.

References

  1. [1]
    Mind - APA Dictionary of Psychology
    Apr 19, 2018 · In this sense, the mind is considered more the province of humans and of human consciousness than of organisms in general. human ...
  2. [2]
    A Neurologist Looks at Mind and Brain: “The Enchanted Loom” - PMC
    The concept of mind encompasses functions that include consciousness, cognition, language, perception, emotion, memory, sleep and dreaming. Thus, we come ...
  3. [3]
    [PDF] The Mind-Body Problem
    With few exceptions, philosopher had accepted the following claims: (1) that one's own mind is better known than one's body, (2) that the mind is.
  4. [4]
    None
    ### Core Definition of the Mind in Philosophy of Mind
  5. [5]
    20th WCP: Mind, Intelligence and Spirit
    ABSTRACT: The mind is a collection of various classes of processes that can be studied empirically. To limit the field of mental processes we must follow ...
  6. [6]
    Mind - Etymology, Origin & Meaning
    Originating from Old English gemynd (memory, intellect) and Proto-Germanic *ga-mundiz, "mind" means the intellect, memory, and to remember or pay attention.
  7. [7]
    Ancient Theories of Soul - Stanford Encyclopedia of Philosophy
    Oct 23, 2003 · Thus the soul, as Plato conceives of it in the Phaedo, is crucially characterized by cognitive and intellectual features: it is something that ...The Greek Notion of Soul · Plato's Theories of Soul · Hellenistic Theories of Soul
  8. [8]
    Aristotle's Psychology - Stanford Encyclopedia of Philosophy
    Jan 11, 2000 · Aristotle describes mind (nous, often also rendered as “intellect ... active and in some ways passive. Although both mind and the sensory ...The Active Mind of De Anima iii 5 · Controversies Surrounding...
  9. [9]
    Dualism - Stanford Encyclopedia of Philosophy
    Aug 19, 2003 · Descartes argues that mind and body are distinct substances characterised by thought (which for Descartes, includes all conscious mental states) ...
  10. [10]
    Functionalism - Stanford Encyclopedia of Philosophy
    Aug 24, 2004 · Functionalism in the philosophy of mind is the doctrine that what makes something a mental state of a particular type does not depend on its internal ...
  11. [11]
    Computational Theory of Mind | Internet Encyclopedia of Philosophy
    The Computational Theory of Mind (CTM) claims that the mind is a computer, so the theory is also known as computationalism.Classical CTM · Computational Neuroscience · Computational Explanation
  12. [12]
    Cognitive Science - Stanford Encyclopedia of Philosophy
    Sep 23, 1996 · Cognitive science is the interdisciplinary study of mind and intelligence, embracing philosophy, psychology, artificial intelligence, neuroscience, linguistics ...
  13. [13]
    Emotion - Stanford Encyclopedia of Philosophy
    Sep 25, 2018 · No aspect of our mental life is more important to the quality and meaning of our existence than the emotions. They are what make life worth ...
  14. [14]
    [PDF] Nagel-What-is-it-like-to-be-a-bat.pdf - UConn Philosophy Department
    WHAT IS IT LIKE TO BE A BAT? CONSCIOUSNESS is what makes the mind-body problem really intractable. Perhaps that is why current discussions of the problem give ...
  15. [15]
    [PDF] David J. Chalmers - The conscious mind - LSE
    I wrote the first version of this work (then known as Toward a Theory of Consciousness) in a heady six-month period in 1992 and 1993.1 had useful discussions ...
  16. [16]
    The Unconscious Mind - PMC - NIH
    This research, in contrast with the cognitive psychology tradition, has led to the view that the unconscious mind is a pervasive, powerful influence over such ...
  17. [17]
    Priming. - APA PsycNet - American Psychological Association
    This chapter is about the wide variety of priming encountered in cognitive and social psychology. In cognitive psychology, the priming paradigm is mainly ...
  18. [18]
    Unconscious influences on decision making: A critical review
    Jan 24, 2014 · This article presents a novel framework for evaluating these claims and reviews evidence from three major bodies of research in which unconscious factors have ...
  19. [19]
    Time of Conscious Intention to Act in Relation to Onset of Cerebral ...
    Aug 6, 2025 · It is concluded that cerebral initiation of a spontaneous, freely voluntary act .can begin unconsciously, that is, before there is any (at least ...
  20. [20]
    Does the Prefrontal Cortex Play an Essential Role in Consciousness ...
    Abstract. A central debate in philosophy and neuroscience pertains to whether PFC activity plays an essential role in the neural basis of consciousness.
  21. [21]
    An integrative view of the role of prefrontal cortex in consciousness
    May 15, 2024 · The PFC has been shown to play a critical role in controlling the levels of consciousness as observed during anesthesia.
  22. [22]
    Memory and consciousness. - APA PsycNet
    Describes laboratory and clinical attempts to relate different memory systems (procedural, semantic, and episodic) to corresponding varieties of consciousness.Missing: types | Show results with:types
  23. [23]
    The Modularity of Mind - MIT Press
    Hardcover · Description. This study synthesizes current information from the various fields of cognitive science in support of a new and exciting theory of mind.
  24. [24]
    Psychology from an empirical standpoint : Brentano, Franz, 1838-1917
    Jun 19, 2023 · Psychology from an empirical standpoint. by: Brentano, Franz, 1838-1917. Publication date: 1973. Topics: Psychology. Publisher: London : ...
  25. [25]
    [PDF] Mind_and_the_World_Order_-_Lewis_05-KEE-260.pdf
    The conceptions presented in this book have grown out of investigations which began in the field of exact logic and its application to mathe matics.
  26. [26]
    [PDF] Consciousness: The First-Person and Third-Person Views
    Dec 30, 1987 · Now, it is a central observation that any smart being would claim to be conscious; it would be third-person-conscious. For a start, it must ...
  27. [27]
    [PDF] Meditations 1 & 2 - rintintin.colorado.edu
    Meditations 1 & 2 by René Descartes (1641) translated by John Cottingham (1984). FIRST MEDITATION. What can be called into doubt. Some years ago I was struck ...
  28. [28]
    [PDF] The Two-Dimensional Argument Against Materialism
    Arguments of this sort include the conceivability argument, the knowledge argument, the explanatory-gap argument, and the property dualism argument. Such.
  29. [29]
    [PDF] The Principles of Human Knowledge - Sandiego
    To do this, you need to have ideas of two principal powers called 'will' and 'understanding', these 17 Page 9 Principles George Berkeley 1–50 ideas being ...
  30. [30]
    [PDF] Correspondence between Descartes and Princess Elisabeth
    All of. Descartes' letters are written from Egmond (Holland) except for two from France in vii.1644, one from The Hague in 6.vi.1647, one from Paris vi.1648) ...
  31. [31]
    [PDF] 13 Remarks on the Mind-Body Question - The Information Philosopher
    F. Dyson, in a very thoughtful article,1 points to the everbroadening scope of scientific inquiry. Whether or not the relation of mind to body.
  32. [32]
    [PDF] Sensations and Brain Processes Author(s): J. J. C. Smart Source
    Sensations and Brain Processes. Author(s): J. J. C. Smart. Source: The Philosophical Review, Vol. 68, No. 2 (Apr., 1959), pp. 141-156. Published by: Duke ...
  33. [33]
    Kim on Mental Causation and Causal Exclusion - jstor
    For three decades Jaegwon Kim has articulated and defended the view that mental properties are distinct from physical properties, are supervenient on phys-.
  34. [34]
    Psychology as the Behaviorist Views it. John B. Watson (1913).
    Psychology, as the behaviorist views it, is a purely objective, experimental branch of natural science which needs introspection as little as do the sciences ...
  35. [35]
    [PDF] Chapter 10 The Nature of Mental States Hilary Putnam - CSULB
    I propose the hypothesis that pain, or the state of being in pain, is a functional state of a whole organism. To explain this it is necessary to introduce some ...
  36. [36]
    [PDF] 2 What Is Functionalism? - Ned Block
    Shoe- maker says, ''On one construal of it, functionalism in the philosophy of mind is the doctrine that mental or psychological terms are in principle ...
  37. [37]
    Emergent Properties - Stanford Encyclopedia of Philosophy
    Aug 10, 2020 · Strong emergentists maintain that at least some higher-level phenomena exhibit a weaker dependence/stronger autonomy than weak emergence permits ...Introduction · Weak Emergence · Strong Emergence · Weak vs. Strong Emergence...
  38. [38]
    Samuel Alexander - Stanford Encyclopedia of Philosophy
    Jun 2, 2014 · He is best known for advancing “British Emergentism”, a movement that held mind “emerges” from matter. Alexander rejected idealism, and ...
  39. [39]
    [PDF] Strong and Weak Emergence - David Chalmers
    Strong emergence has much more radical consequences than weak emergence. If there are phenomena that are strongly emergent with respect to the domain of physics ...
  40. [40]
    An information integration theory of consciousness
    Nov 2, 2004 · The theory states that the quantity of consciousness available to a system can be measured as the Φ value of a complex of elements. Φ is the ...Missing: seminal | Show results with:seminal
  41. [41]
    René Descartes: The Mind-Body Distinction
    Descartes' mind-body dualism posits that mind (thinking, non-extended) and body (extended, non-thinking) are distinct substances that can exist without each ...
  42. [42]
    Epiphenomenalism - Stanford Encyclopedia of Philosophy
    Jan 18, 1999 · Epiphenomenalism is the view that mental events are caused by physical events in the brain, but have no effects upon any physical events.Traditional Arguments (B) Con... · Self-stultification · Arguments in the Age of...
  43. [43]
    Leibniz's Philosophy of Mind
    Sep 22, 1997 · Leibniz's account of mind-body causation was in terms of his famous doctrine of the pre-established harmony.Denial of Mind-Body... · Language and Mind · Perception and Appetition
  44. [44]
    Occasionalism - Stanford Encyclopedia of Philosophy
    Oct 20, 2008 · One way to view occasionalism is to see it as one of three possible responses to the aforementioned problem of mind-body interaction. The ...The History of Occasionalism · Occasionalism in Context · The Arguments for...
  45. [45]
    [PDF] Facing Up to the Problem of Consciousness - David Chalmers
    The really hard problem of consciousness is the problem of experience. When we think and perceive, there is a whir of information-processing, but there is ...
  46. [46]
    [PDF] What Mary Didn't Know Frank Jackson The Journal of Philosophy ...
    Dec 17, 2007 · Mary, confined to a black-and-white room, would not know what it is like to sense red, despite knowing all physical facts, which is the point ...
  47. [47]
    Anomalous Monism - Stanford Encyclopedia of Philosophy
    Nov 8, 2005 · ... mental events – what makes an event a mental event. Davidson argues that part of what identifies events as mental is their causal nature.E. Mental Causation and... · D. Mental Anomalism · C. Physical Causal Closure...
  48. [48]
    [PDF] Towards a neurobiological theory of consciousness
    The effects of the 40 Hz oscillations is probably greater than the same amount of random firing for two reasons: first, because spikes arriving at a neuron ...
  49. [49]
    Can binocular rivalry reveal neural correlates of consciousness?
    This essay critically examines the extent to which binocular rivalry can provide important clues about the neural correlates of conscious visual perception.
  50. [50]
    A default mode of brain function - PNAS
    These decreases suggest the existence of an organized, baseline default mode of brain function that is suspended during specific goal-directed behaviors.
  51. [51]
    Experience sampling during fMRI reveals default network and ...
    A particularly prominent view is that default network recruitment reflects internally focused thought (2, 3) that can occur in the form of mind wandering (4–6) ...
  52. [52]
    SLEEP AND AROUSAL: Thalamocortical Mechanisms
    Thalamocortical activity exhibits two distinct states: (a) synchronized rhyth- mic activity in the form of delta, spindle, and other slow waves during EEG-.
  53. [53]
    Thalamic contributions to the state and contents of consciousness
    May 15, 2024 · The thalamus is a particularly important downstream target of the ascending arousal system, and its specific interactions with cortical circuits ...
  54. [54]
    The Organization Of Behavior A Neuropsychological Theory
    Jan 23, 2017 · The Organization Of Behavior A Neuropsychological Theory. by: D. O. Hebb. Publication date: 1949. Topics: RMSC. Collection: digitallibraryindia ...
  55. [55]
    The Organization of Behavior: A Neuropsychological Theory
    Apr 11, 2005 · Hebb was also the first to examine the mechanisms by which environment and experience can influence brain structure and function, and his ideas ...<|control11|><|separator|>
  56. [56]
    EEG Oscillations Reveal Neural Correlates of Evidence Accumulation
    In this study we examine what frequency bands of brain oscillations best reflect evidence accumulation as predicted by accumulator models. We also test whether ...
  57. [57]
    Article Population coding of predator imminence in the hypothalamus
    Apr 16, 2025 · Summary. Hypothalamic VMHdmSF1 neurons are activated by predator cues and are necessary and sufficient for instinctive defensive responses.
  58. [58]
    A Ventromedial Hypothalamic Neuron Subset Encodes a ... - bioRxiv
    May 30, 2025 · Summary. The VMHSF1 neurons encode a predator-orientated internal state that drives innate defensive responses.
  59. [59]
    Distinct neuron populations in the hypothalamus encode states ...
    May 13, 2025 · "Using optogenetics to turn these cells off or on, we showed that these cells were necessary for a mouse to show fear behaviors in response to a ...<|control11|><|separator|>
  60. [60]
    [PDF] Reconsidering the evidence for learning in single cells
    Jan 4, 2021 · This raises the question of whether unicellular organisms are also capable of learning, despite lacking nervous systems, as an evolutionary ...
  61. [61]
    [PDF] The Distribution and Evolution of Animal Consciousness
    All animals are, to some degree, capable of selectively processing and responding to environmental information, and very complex cognition can in theory occur ...
  62. [62]
    The evolutionary and genetic origins of consciousness in the ...
    Hameroff (1998) suggested that consciousness first evolved in the Cambrian in simple worms, urchins, or even in one-celled organisms (suctorians), due to ...
  63. [63]
    The reptilian brain - PMC - PubMed Central - NIH
    Apr 20, 2015 · Surrounding the R-complex is the limbic system or mammalian brain, which evolved tens of millions of years ago in ancestors who were mammal but ...
  64. [64]
    https://pmc.ncbi.nlm.nih.gov/articles/PMC4406946/
  65. [65]
    Human Genetics: The Evolving Story of FOXP2 - ScienceDirect.com
    Jan 21, 2019 · FOXP2 mutations cause a speech and language disorder, raising interest in potential roles of this gene in human evolution.
  66. [66]
    Mirror neurons - Scholarpedia
    Oct 21, 2011 · Mirror neurons represent a distinctive class of neurons that discharge both when the monkey executes a motor act and when it observes another individual.
  67. [67]
    The Smithsonian Institution's Human Origins Program - Brains
    Jan 3, 2024 · Over the course of human evolution, brain size tripled. The modern human brain is the largest and most complex of any living primate.
  68. [68]
    Hominin cognitive evolution: identifying patterns and processes in ...
    We show that hominin brain evolution was likely to be the result of a mix of processes; punctuated changes at approximately 100 kya, 1 Mya and 1.8 Mya.
  69. [69]
    Embryology, Neural Tube - StatPearls - NCBI Bookshelf - NIH
    It starts during the 3rd and 4th week of gestation. This process is called primary neurulation, and it begins with an open neural plate, then ends with the ...
  70. [70]
    The Brain before Birth: Using fMRI to Explore the Secrets of Fetal ...
    Nov 20, 2018 · In a process known as synaptic pruning, the brain organizes its connectome to perform more efficiently, removing inefficient connections to ...
  71. [71]
    Developmental Stages of Social Emotional Development in Children
    Sep 18, 2022 · Social-emotional development includes self (temperament) and attachment. Milestones include smiling (1-2 months), stranger anxiety (6-12 months ...Continuing Education Activity · Introduction · Function · Clinical Significance
  72. [72]
    Prefrontal cortex and executive function in young children - Frontiers
    Dec 16, 2013 · Recent neuroanatomical research suggests that children with ADHD exhibit a marked delay in maturation of the prefrontal areas (Shaw et al., 2007) ...Abstract · Neural Basis of Cognitive... · EF in Children With Attention...
  73. [73]
    Adolescent brain development in normality and psychopathology - NIH
    The field of adolescent brain development has flourished, as researchers have investigated the underpinnings of adolescent risk-taking behaviors.
  74. [74]
    Neural plasticity across the lifespan - PMC - NIH
    Dec 1, 2016 · A review of current data suggests that plasticity encompasses many distinct phenomena, some of which operate across most or all of the lifespan.Neural Plasticity Across The... · Introduction · Hebbian Plasticity
  75. [75]
    The Critical Period Hypothesis in Second Language Acquisition - NIH
    Lenneberg's critical period stretched from two years of age to puberty (which he posits at about 14 years of age) [2], whereas other scholars have drawn the ...
  76. [76]
    Environmental and genetic influences on early attachment - PMC
    Environmental factors. Bowlby's attachment theory is a truly environmental theory as it has explained individual differences in attachment patterns (attachment ...
  77. [77]
    Chimpanzees: Self-Recognition - Science
    After prolonged exposure to their reflected images in mirrors, chimpanzees marked with red dye showed evidence of being able to recognize their own reflections.
  78. [78]
    [PDF] The Cambridge Declaration on Consciousness*
    Jul 7, 2012 · The Declaration was publicly proclaimed in Cambridge, UK, on July 7, 2012, at the Francis Crick Memorial. Conference on Consciousness in Human ...Missing: original source
  79. [79]
    Neural Correlates of Executive Control in the Avian Brain
    Our findings indicate that neurons in the avian nidopallium caudolaterale participate in one of the core forms of executive control.
  80. [80]
    [PDF] A GENERAL PROBLEM-SOLVING PROGRAM FOR A COMPUTER
    This paper deals with the theory of problem solving. It describes a program for a digital computer, called. General Problem Solver I (GPS), which is part of ...
  81. [81]
    Parallel Distributed Processing - MIT Press
    These volumes by a pioneering neurocomputing group suggest that the answer lies in the massively parallel architecture of the human mind.
  82. [82]
    Learning representations by back-propagating errors - Nature
    Oct 9, 1986 · Cite this article. Rumelhart, D., Hinton, G. & Williams, R. Learning representations by back-propagating errors. Nature 323, 533–536 (1986).
  83. [83]
    http://iiif.library.cmu.edu/file/Newell_box00039_fld03042_doc0001/Newell_box00039_fld03042_doc0001.pdf
  84. [84]
    How large language models encode theory-of-mind - Nature
    Aug 28, 2025 · This paper investigates the emergence of Theory-of-Mind (ToM) capabilities in large language models (LLMs) from a mechanistic perspective, ...
  85. [85]
    Saudi Arabia becomes first country to grant citizenship to a robot
    Oct 26, 2017 · Sophia made global headlines when she was granted Saudi citizenship, making the kingdom the first country in the world to offer its citizenship to a robot.Missing: source | Show results with:source
  86. [86]
    Sophia - Hanson Robotics
    She is the world's first robot citizen and the first robot Innovation Ambassador for the United Nations Development Programme. Sophia is now a household ...
  87. [87]
    Attention: The grounds of self‐regulated cognition - Rueda - 2023
    Oct 25, 2021 · In this article we argue that paying attention consists in tuning the mind with the environment in a conscious and controlled mode.
  88. [88]
    The REM Sleep–Memory Consolidation Hypothesis - PMC
    It has been hypothesized that REM (rapid eye movement) sleep has an important role in memory consolidation. The evidence for this hypothesis is reviewed and ...
  89. [89]
    [PDF] A Review of Daniel Kahneman's Thinking, Fast and Slow
    Nov 16, 2012 · As the title of the book suggests, System 1 corresponds to thinking fast, and System 2 to thinking slow. Kahneman describes System 1 in many ...
  90. [90]
    What Is Flow in Positive Psychology?
    Oct 9, 2025 · Flow is a state where you are so immersed in an activity that you lose track of time, self-consciousness fades, and you feel a deep sense of ...What Is Flow in Positive... · The Flow Theory of Optimal...
  91. [91]
    PERMA™ Theory of Well-Being and PERMA™ Workshops
    Seligman's PERMA™ theory of well-being is an attempt to answer these fundamental questions. There are five building blocks that enable flourishing – Positive ...Missing: states | Show results with:states
  92. [92]
    Emotion Regulation, Parasympathetic Function, and Psychological ...
    Aug 2, 2022 · Emotion regulation skills play an important role in the relationship between stressful life events and mental health outcomes, such as ...Abstract · Introduction · Materials and Methods · Discussion
  93. [93]
    'Dunbar's number' deconstructed - PMC - NIH
    May 5, 2021 · Dunbar's number is the idea that humans can maintain stable relationships with about 150 people, based on primate brain size.<|separator|>
  94. [94]
    Wechsler Intelligence Scale - an overview | ScienceDirect Topics
    The Wechsler scales yield a standard score with a mean of 100 and a standard deviation of 15. The WIPPSI-R is appropriate for children ages 3 years to 1 years ...
  95. [95]
    Gardner's Theory Of Multiple Intelligences - Simply Psychology
    Mar 26, 2025 · Howard Gardner's theory of multiple intelligences posits that individuals possess various distinct types of intelligences, rather than a single ...
  96. [96]
    Chronotype and synchrony effects in human cognitive performance
    Based on the findings of this review, we conclude that chronotype (on its own) does not strongly or consistently impact cognitive function in healthy adults. We ...Results · Chronotype, Tod And... · Chronotype, Tod, And...
  97. [97]
    Diagnostic and Statistical Manual of Mental Disorders (DSM-5-TR)
    The manual will help clinicians and researchers define and classify mental disorders, which can improve diagnoses, treatment, and research.About DSM-5-TR · Updates to DSM Criteria, Text · Educational Resources
  98. [98]
    [PDF] Major depressive disorder - American Psychiatric Association
    DSM is the manual used by clinicians and researchers to diagnose and classify mental disorders. The American Psychiatric. Association (APA) will publish DSM-5- ...
  99. [99]
    [PDF] Bipolar I and Bipolar II Disorders | American Psychiatric Association
    The definitions for the bipolar severity specifiers in DSM-5 (i.e., mild, moderate, severe) make sense only if the current episode is a major depressive episode ...
  100. [100]
    Generalized Anxiety Disorder - National Institute of Mental Health
    Prevalence of Generalized Anxiety Disorder Among Adults​​ An estimated 5.7% of U.S. adults experience generalized anxiety disorder at some time in their lives.Prevalence of Generalized... · Generalized Anxiety Disorder...
  101. [101]
    None
    ### DSM-5 Criteria for PTSD: Flashbacks and Avoidance
  102. [102]
    None
    ### DSM-5 Diagnostic Criteria for Autism Spectrum Disorder
  103. [103]
    None
    ### DSM-5 Diagnostic Criteria for ADHD
  104. [104]
    The Role of Dopamine in Schizophrenia from a Neurobiological and ...
    May 19, 2014 · The revised dopamine hypothesis states that dopamine abnormalities in the mesolimbic and prefrontal brain regions exist in schizophrenia.
  105. [105]
    Psilocybin with psychotherapeutic support for treatment-resistant ...
    Oct 2, 2025 · Modern clinical trials have assessed the efficacy of psilocybin therapy in MDD and TRD populations, with over 500 participants across nine ...
  106. [106]
    Psychedelic and Dissociative Drugs as Medicines - NIDA - NIH
    Jan 24, 2024 · The FDA has also granted “breakthrough therapy” designation for two formulations of psilocybin being studied for safety and efficacy as a ...
  107. [107]
    Classical Conditioning - StatPearls - NCBI Bookshelf - NIH
    Pavlov observed several phenomena related to classical conditioning. He found that the rate of acquisition during the initial stages of learning depended on the ...
  108. [108]
    Operant Conditioning - PMC - NIH
    The term operant conditioning was coined by B. F. Skinner in 1937 in the context of reflex physiology, to differentiate what he was interested in—behavior that ...
  109. [109]
    Cognitive Behavior Therapy - StatPearls - NCBI Bookshelf - NIH
    In the 1960s, Aaron Beck developed cognitive behavior therapy (CBT) or cognitive therapy. Since then, it has been extensively researched and found to be ...
  110. [110]
    Piaget - StatPearls - NCBI Bookshelf - NIH
    Through assimilation and accommodation of the object, Piaget's theory of cognitive development is characterized by a stepwise move toward adaptation.
  111. [111]
    Person-Centered Therapy (Rogerian Therapy) - StatPearls - NCBI
    Feb 9, 2023 · Person-centered therapy, also referred to as non-directive, client-centered, or Rogerian therapy, was pioneered by Carl Rogers in the early 1940s.
  112. [112]
    [PDF] Mind in Society
    Vygotsky believed that the internalization of culturally produced sign systems hrings 'lbout hehavioral transformations and forms the bridge between early and ...
  113. [113]
    Minnesota Multiphasic Personality Inventory - StatPearls - NCBI - NIH
    May 27, 2020 · The Minnesota Multiphasic Personality Inventory (MMPI) is the most common psychometric test devised to assess personality traits and psychopathology.Missing: source | Show results with:source
  114. [114]
    Self-Knowledge - Stanford Encyclopedia of Philosophy
    Feb 7, 2003 · By assimilating introspection to perception, inner sense accounts construe mentality as epistemically continuous with the nonmental, and thus ...
  115. [115]
    Other Minds - Stanford Encyclopedia of Philosophy
    May 2, 2019 · The problem here has most commonly been thought to arise within epistemology: how do I know (or how can I justify the belief) that other beings exist who have ...
  116. [116]
    Extended Mind | Analysis - Oxford Academic
    Andy Clark, David Chalmers; The Extended Mind, Analysis, Volume 58, Issue 1, 1 January 1998, Pages 7–19, https://doi.org/10.1093/analys/58.1.7.
  117. [117]
    Compatibilism - Stanford Encyclopedia of Philosophy
    Apr 26, 2004 · Compatibilism is the thesis that free will is compatible with determinism. Because free will is typically taken to be a necessary condition ...Arguments for Incompatibilism · State of the Art · IncompatibilistMissing: brain | Show results with:brain
  118. [118]
    Phenomenology - Stanford Encyclopedia of Philosophy
    Nov 16, 2003 · We are to practice phenomenology, Husserl proposed, by “bracketing” the question of the existence of the natural world around us. We thereby ...The History and Varieties of... · Phenomenology and... · Phenomenology in...
  119. [119]
    Self models - Scholarpedia
    Oct 25, 2007 · The concept of a self-model plays the central role in a philosophical theory of consciousness, the phenomenal self and the first-person perspective.
  120. [120]
    (PDF) Newell and Simon's Logic Theorist: Historical Background ...
    Aug 10, 2025 · Notably, Newell and Simon's development of the Logic Theorist and General Problem Solver in the 1950s demonstrated that computers could ...
  121. [121]
    [PDF] Cognitive Science: The Newest Science of the Artificial*
    Cognitive science is, of course, not really a new discipline, but a recognition of a fundamental set of common concerns shared by the disciplines of ...
  122. [122]
    ACT-R
    ACT-R is a cognitive architecture: a theory for simulating and understanding human cognition. Researchers working on ACT-R strive to understand how people ...About · Software · 2025 ACT-R Workshop · Workshops
  123. [123]
    [PDF] A simple theory of complex cognition - ACT-R
    A production-sys- tem model called ACTE was proposed to embody this joint procedural-declarative theory. After 7 years of working with variants of that system, ...
  124. [124]
    Explaining Embodied Cognition Results - Lakoff - Wiley Online Library
    Sep 7, 2012 · Primary metaphors are motivated by embodied experiences coming together regularly. For example, when children are held affectionately by their ...Abstract · Metaphorical thought and... · Explaining experimental...
  125. [125]
    Embodied Imagination: Lakoff and Johnson's Experientialist View of ...
    This paper reviews an embodied or experientialist view of conceptual understanding. It focuses on George Lakoff and Mark Johnson's theory of embodied cognition.
  126. [126]
    The importance of Marr's three levels of analysis for understanding ...
    Jan 19, 2017 · Marr proposed that complex information processing systems be analysed at three different levels, those of computation, algorithm and implementation.
  127. [127]
    Bayesian brain theory: Computational neuroscience of belief
    Feb 6, 2025 · Bayesian brain theory (BBT) mathematically formalizes the dynamic of information processing through belief encoding and perceptual inference.
  128. [128]
    An adaptive representational account of predictive processing in ...
    Mar 14, 2025 · The predictive processing theory advocates that the brain is a hierarchical predictive model based on Bayesian inference, and its purpose is to ...
  129. [129]
    http://act-r.psy.cmu.edu/wordpress/wp-content/uploads/2012/12/97ACT.ASimpleTheory.pdf
  130. [130]
    Thought and Language - MIT Press
    In this highly original exploration of human mental development, Vygotsky analyzes the relationship between words and consciousness, arguing that speech is ...Missing: sociocultural | Show results with:sociocultural
  131. [131]
    [PDF] LINGUISTIC RELATIVITY
    The linguistic relativity hypothesis, the proposal that the particular language we speak influences the way we think about reality, forms one part of the.Missing: variants | Show results with:variants
  132. [132]
    https://academic.oup.com/book/338/chapter/134987510
  133. [133]
    https://www.sciencedirect.com/science/article/abs/pii/S0306452224007048
  134. [134]
    Moral Cognition - Joshua Greene
    As explained in this paper and in Moral Tribes, our dual-process moral brains are very good at solving some kinds of moral problems and very bad at solving ...
  135. [135]
    [PDF] The Cognitive Neuroscience of Moral Judgment* Joshua D. Greene
    According to the dual-process theory, these behavioral effects are the result of the aforementioned conflict between emotional intuition and controlled ...Missing: implications | Show results with:implications<|separator|>
  136. [136]
    insanity defense | Wex | US Law | LII / Legal Information Institute
    The ''M'Naghten Rule'' ... The first famous legal test for insanity came in 1843, in theM'Naghten case. Englishman Daniel M'Naghten shot and killed the secretary ...
  137. [137]
    18 U.S. Code § 4241 - Determination of mental competency to stand ...
    The defendant or the attorney for the Government may file a motion for a hearing to determine the mental competency of the defendant.
  138. [138]
    Competency to Stand Trial in Criminal Law Cases - Justia
    Oct 18, 2025 · A defendant cannot be convicted of a crime if they are not mentally competent to stand trial. This would violate constitutional protections for defendants.
  139. [139]
    Neurorights, Mental Privacy, and Mind Reading | Neuroethics
    Jul 9, 2024 · ... mental privacy; despite an extensive record of privacy in law and philosophy, there is no universally accepted definition of mental privacy [1].
  140. [140]
    Ethics of neurotechnology - UNESCO
    Mental privacy and brain data confidentiality. Brain data reveals our most private thoughts; its collection through neurotechnology must be strictly ...Towards an International... · Ad Hoc Expert Group · UNESCO appoints...
  141. [141]
    Animal Rights Theory and Utilitarianism: Relative Normative Guidance
    In Animal Liberation, Singer argues that in assessing the consequences of our actions, it is necessary to take the interests of animals seriously and to weigh ...<|separator|>
  142. [142]
    EU AI Act: first regulation on artificial intelligence | Topics
    Feb 19, 2025 · In June 2024, the EU adopted the world's first rules on AI. The Artificial Intelligence Act will be fully applicable 24 months after entry into ...
  143. [143]
    A Narrative Overview of Nootropics and “Smart Drug” Use and Misuse
    Sep 11, 2025 · While nootropics are designed to treat cognitive problems linked to medical conditions, many healthy people now use “smart drugs” to try to ...
  144. [144]
    Bioethics and Transhumanism - Oxford Academic
    May 11, 2017 · For example, transhumanists consider nootropics as a human enhancement technology, because nootropics ... nootropics, “mind-uploading,” and more.
  145. [145]
    Ethical Issues and Recommendations in Psychedelic Research and ...
    Aug 7, 2025 · One author described how participants may consent to one option then change their mind during therapy and how assessing whether a client had ...
  146. [146]
    Psychedelic Use in Psychiatry Demands New Informed Consent ...
    Aug 27, 2024 · Bioethicists call for a new paradigm for obtaining informed consent from patients prior to the administration of psychedelics—to ensure they ...<|control11|><|separator|>