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Laughter

Laughter is a universal physiological and emotional response in humans, characterized by rhythmic, involuntary contractions of the diaphragm and other respiratory muscles, producing audible vocalizations and often accompanied by facial expressions such as smiling or grinning. It typically arises from stimuli like humor, social cues, or physical sensations such as tickling, serving as a nonverbal signal of positive affect and shared understanding. This response is distinct from other vocalizations, involving rapid bursts of exhalation and laryngeal activity that differentiate it from speech or crying.^[1] Physiologically, laughter triggers a cascade of bodily changes, including increased oxygenation through deeper breathing, stimulation of the heart, lungs, and muscles, and the release of endorphins and other neurotransmitters that promote feelings of well-being.^[2] These effects can lower blood pressure, enhance immune function, and reduce levels of stress hormones like cortisol, contributing to short-term relaxation and pain relief.^[3] For instance, studies have shown that laughter increases stroke volume and cardiac output while decreasing oxygen consumption during the activity.^[3] Psychologically, it fosters emotional resilience by alleviating anxiety and depression, often through the activation of reward pathways in the brain similar to those involved in social bonding.^[4] From an evolutionary perspective, laughter likely originated as a preadaptation in primates, gradually evolving into a sophisticated tool for social cohesion among early humans.^[5] It functions as a form of chorusing that synchronizes group interactions, triggering endorphin release to strengthen bonds and facilitate cooperation, particularly as hominin group sizes expanded.^[6] This social role underscores laughter's prevalence in interpersonal contexts, where over 80% of instances occur in response to others rather than solitary thoughts.^[7] Culturally, laughter manifests in diverse forms, from spontaneous guffaws to polite chuckles, reflecting its adaptability across societies while retaining core biological underpinnings.^[5]

Definition and Characteristics

Physical and Vocal Aspects

Laughter manifests through a combination of facial expressions, vocalizations, and bodily movements that are universally recognizable across human cultures. The primary facial expression associated with genuine laughter is the Duchenne smile, characterized by the contraction of the zygomaticus major muscle, which elevates the corners of the mouth, and the orbicularis oculi muscle, which raises the cheeks and produces crow's feet wrinkles around the eyes.^[8] This distinguishes it from a mere social smile, as the eye involvement signals authentic positive emotion. These facial changes occur rapidly, often within milliseconds of the laughter trigger, enhancing the expressiveness of the response.^[9] Vocalizations form the audible core of laughter, produced by the vibration of the vocal folds without the articulation of words, resulting in a series of rhythmic, vowel-like bursts such as "ha-ha" or "he-he." Acoustically, these sounds feature short notes averaging about 75 milliseconds in duration, repeated in sequences, with fundamental frequencies typically ranging from 100 to 700 Hz, with means around 200 Hz for males and 400 Hz for females, and ranges showing overlap but generally higher values for females.^[10]^[11] The voicing arises from pulsed airflow through adducted vocal folds, creating a noisy yet periodic quality distinct from speech, and can include unvoiced or mixed elements in some variants.^[12] Bodily movements accompany these vocal efforts, including spasmodic contractions of the diaphragm and chest muscles, leading to shoulder shaking, head tilting, and intermittent gasping as air is expelled in bursts following a deep initial inspiration.^[13] These physical actions engage the abdominal and intercostal muscles, producing visible tremors that amplify the overall display.^[14] Episodes of laughter vary in duration and intensity, generally lasting about 1 to 3 seconds per bout, with intensity influenced by the number of vocal repetitions and the force of muscular contractions.^[12] Softer laughter may involve subtle shoulder movements and lower-volume vocalizations, while intense episodes feature prolonged shaking and louder, more frequent bursts, reflecting the emotional arousal level.

Types and Variations

Laughter manifests in diverse forms, classified primarily by intent, emotional basis, and social context. Genuine laughter, also known as spontaneous or Duchenne laughter, arises from authentic joy or amusement and is characterized by involuntary, heartfelt responses to humorous stimuli.^[15] In contrast, social laughter serves affiliative or polite functions, often occurring in conversational settings to build rapport or signal agreement, even when the trigger lacks inherent humor.^[16] Nervous laughter functions as a de-escalative mechanism, providing relief from anxiety or tension during awkward or stressful situations.^[17] Cruel laughter, rooted in derision or schadenfreude, expresses dominance or amusement at others' misfortune, often diminishing social bonds.^[18] Simulated laughter, or forced laughter, is deliberately produced to conform to social expectations, such as in performative or obligatory scenarios.^[15] Cultural norms significantly influence the expression of laughter, leading to variations in volume, visibility, and restraint. In many Western cultures, laughter tends to be vocal and expressive, aligning with values of high emotional arousal and openness.^[19] Conversely, in some East Asian contexts, such as those influenced by Confucian principles emphasizing harmony and modesty, laughter is often more subdued, sometimes covered with the hand or expressed silently to avoid drawing undue attention or disrupting group equilibrium.^[20] Developmentally, laughter emerges in human infants around 3 to 4 months of age, initially as simple vocalizations in response to playful social interactions like tickling or peek-a-boo games, marking an early milestone in emotional and communicative growth.^[21] By 5 to 7 months, these responses become more frequent and differentiated, with infants laughing sooner and more robustly in the presence of encouraging parental cues, laying the foundation for the complex, context-dependent varieties observed in adulthood.^[21] Rare variants include pathological laughter, which occurs involuntarily and disproportionately to emotional context, as seen in conditions like pseudobulbar affect where episodes of uncontrollable laughing arise without genuine mirth.^[22]

Physiological Mechanisms

Neurological Processes

Laughter involves coordinated activation across multiple brain regions, reflecting its hybrid nature as both an emotional and motor response. The periaqueductal gray (PAG) in the midbrain plays a central role in motor control, gating the initiation of laughter vocalizations and integrating sensory inputs for reflexive expressions.^[23] The hypothalamus contributes to emotional integration, modulating affective states that drive laughter through connections to the limbic system and influencing autonomic responses.^[24] Meanwhile, the prefrontal cortex, particularly the ventromedial and medial regions, processes social context, enabling the interpretation of laughter's communicative intent and its alignment with interpersonal dynamics.^[1] Neural circuitry underlying laughter encompasses reward pathways and mechanisms for social contagion. Activation of the mesolimbic reward system, including dopamine release in the nucleus accumbens, occurs during mirthful laughter, reinforcing its pleasurable aspects similar to other rewarding stimuli.^[25] Contagious laughter, where hearing others laugh triggers one's own response, implicates mirror neuron networks in the inferior frontal gyrus and premotor areas, which facilitate imitation of observed or auditory emotional expressions.^[26] Functional magnetic resonance imaging (fMRI) and electroencephalography (EEG) studies reveal distinct patterns of activation, underscoring laughter's rapid emotional-motor integration. fMRI data show hybrid responses with early onset in the limbic system—including the amygdala and anterior cingulate cortex—for emotional processing, followed by motor areas like the supplementary motor area and frontal operculum for execution.^[23] EEG complements this by capturing temporal dynamics, such as pre-laughter preparatory activity in the periaqueductal gray approximately two seconds prior to vocalization.^[23] Recent neuroimaging up to 2025 highlights hemispheric asymmetries, with greater right-hemisphere connectivity observed during positive laughter and social smiling in infants, suggesting early lateralization for prosocial emotional processing.^[27] Advanced fMRI techniques further indicate that positive laughter engages more bilateral reward and motor networks, while negative or pathological forms show right-hemisphere dominance linked to emotional dysregulation.^[28]

Anatomical Involvement

Laughter's physical manifestations arise from coordinated actions across multiple anatomical systems, primarily involving the respiratory, muscular, and vocal structures. The respiratory system plays a central role through rapid, rhythmic contractions of the diaphragm, the primary muscle of respiration, which force air out of the lungs in irregular bursts. These diaphragmatic spasms, occurring at frequencies of 3 to 8 Hz, reduce lung volume suddenly across all compartments, producing the heaving quality of laughter and the associated audible exhalations.^[29] Accompanying intercostal and abdominal muscles further modulate this process, enhancing the expulsion of air and contributing to the overall convulsive rhythm.^[30] Facial and skeletal musculature provides the visible expressions of laughter, with key involvement from specific muscles in the face and torso. The zygomaticus major muscle, extending from the zygomatic bone to the corners of the mouth, contracts to pull the mouth upward into a broad smile, while the orbicularis oculi muscle around the eyes tightens to create the characteristic crinkling or "Duchenne" marker of genuine amusement.^[31] In vigorous laughter, abdominal muscles such as the rectus abdominis, internal obliques, and transverse abdominis engage in powerful, repetitive contractions, driving the diaphragm's action and producing the bodily convulsions or "doubling over" often observed.^[32] These muscular activations resemble those in moderate aerobic exercise, temporarily increasing heart rate and oxygen demand.^[33] The vocal tract generates laughter's distinctive sounds through specialized mechanics at the larynx and beyond. Rhythmic glottal pulses—brief openings and closures of the vocal folds—produce a series of unpitched, pulsed excitations at rates similar to the diaphragmatic contractions, resulting in the staccato bursts like "ha-ha-ha." Unlike speech, which relies on sustained phonation and precise articulation, laughter's vocal output features abrupt, less modulated airflow through the pharynx and oral cavity, often with minimal vowel shaping to emphasize the raw, repetitive quality.^[34] Laughter episodes trigger rapid hormonal responses that amplify its pleasurable effects. Endorphins, the body's natural opioids, are released immediately from the pituitary gland and hypothalamus, binding to receptors in the brain to induce euphoria and pain relief.^[35] In social laughter, oxytocin levels also rise, fostering trust and bonding by acting on limbic system pathways, though this response is more pronounced in group settings.^[36] These releases occur within seconds of onset, linking the anatomical output to broader emotional rewards.

Evolutionary and Biological Perspectives

Origins in Human Evolution

Laughter is believed to have originated as an exaptation from the play vocalizations of primate ancestors, evolving from rhythmic, labored breathing patterns observed during rough-and-tumble play that signaled non-threatening, cooperative interactions.^[37] This adaptation likely served to indicate safety and reduce tension in social encounters, transforming a physiological response to physical play into a broader communicative tool that fostered group bonding among early humans.^[38] Evolutionary biologists propose that such vocalizations provided an adaptive advantage by promoting affiliation and coordination in increasingly complex social groups, distinguishing human laughter from mere play signals through its ritualized form and emotional expressiveness.^[5] Fossil and comparative anatomical evidence suggests that proto-laughter emerged in early hominids around 2.5 million years ago, coinciding with the rise of the genus Homo and the development of larger social networks that demanded enhanced cohesion for survival.^[6] This timeline aligns with archaeological indicators of increased group living, where laughter-like vocalizations may have reinforced trust and cooperative behaviors essential for hunting, foraging, and defense against predators.^[39] While direct genetic markers specific to laughter remain elusive, phylogenetic analyses of vocal tract evolution point to shared ancestry with great ape play calls, underscoring laughter's role in maintaining social harmony during pivotal stages of human ancestry.^[40] In terms of comparative linguistics, human laughter is thought to predate the evolution of spoken language by millions of years, functioning as a pre-verbal mechanism for emotional signaling and social synchronization.^[41] This ancient vocalization likely facilitated rudimentary communication in proto-human groups, allowing individuals to convey shared positive affect without words, and serving as a foundational element for later linguistic developments.^[42] Recent phylogenetic studies, including those post-2020, reinforce this view by reconstructing laughter's trajectory through hominid lineages, highlighting its persistence as a universal, non-linguistic bond-strengthener that predates complex syntax and semantics.^[43]

Laughter in Non-Human Animals

Laughter-like vocalizations have been observed in various non-human primates during social play, providing comparative insights into the evolutionary roots of such behaviors. In chimpanzees (Pan troglodytes), distinct play vocalizations, often described as breathy pants or laughter-like calls, occur predominantly during rough-and-tumble interactions, accompanied by open-mouth play faces that mirror human expressions of amusement.^[44] These vocalizations are elicited by physical contact in both gentle and vigorous play, suggesting a role in signaling non-threatening intent and prolonging playful engagement.^[45] Similarly, bonobos (Pan paniscus) produce breathy, chuckling calls during play chases and tickling, characterized by vocal cord vibrations that resemble the rhythmic panting in human laughter.^[46] A 2025 study found that bonobos exhibit increased optimism after hearing conspecific laughter, providing experimental evidence of emotional contagion and positive affective responses in great apes.^[47] These sounds in great apes highlight shared acoustic features with human laughter, potentially linked to common reward pathways in the brain.^[48] Among rodents, laboratory rats (Rattus norvegicus) emit ultrasonic chirps at approximately 50 kHz during tickling and rough-and-tumble play, interpreted as an analogue to laughter due to their association with positive affective states.^[49] These vocalizations are elicited by manual stimulation mimicking conspecific play, and their production correlates with increased dopamine release in the nucleus accumbens, a key region for reward processing.^[50] Notably, administration of dopamine blockers, such as those targeting D2 receptors, abolishes these 50 kHz calls, underscoring the neurochemical basis of this response and its similarity to mechanisms underlying human joy.^[51] Evidence of laughter-like behaviors extends to other mammals, including canids and cetaceans. Domestic dogs (Canis familiaris) produce rapid, forced panting sounds, termed "play pants," during interactive play bouts, often paired with play bows to invite continued engagement and reduce aggression.^[52] Playback of these vocalizations has been shown to calm shelter dogs, eliciting pro-social responses and decreasing stress-related behaviors.^[53] In bottlenose dolphins (Tursiops truncatus), pulsed burst sounds—short, high-frequency clicks combined with whistles—emerge during play-fighting, distinguishing them from aggressive signals and serving to maintain affiliative interactions in social groups.^[54] These findings have sparked ethical debates on anthropomorphism in animal emotion research, with scholars advocating for critical, evidence-based attributions to avoid over-interpreting human-like qualities while acknowledging observable behavioral parallels, as seen in studies of rat chirps and ape play vocalizations.^[55] Recent research as of 2025 has also confirmed laughter-like vocalizations in birds, such as high-pitched calls in the kea parrot (Nestor notabilis), suggesting an even broader phylogenetic distribution across mammals and birds.^[56]

Functions and Roles

Health and Physiological Benefits

Laughter has been empirically linked to several physiological benefits, enhancing overall health through mechanisms that support immune function, cardiovascular health, pain modulation, and stress reduction. These effects stem from laughter's ability to trigger neurochemical changes, such as the release of beneficial hormones and peptides, which promote homeostasis and resilience in the body. One key benefit is the boost to the immune system, where laughter increases secretory immunoglobulin A (sIgA) levels, a primary antibody that defends mucosal surfaces against pathogens. Studies have shown that exposure to humorous stimuli leading to mirthful laughter elevates sIgA concentrations, potentially enhancing mucosal immunity.^[57] Additionally, laughter augments natural killer (NK) cell activity, which plays a crucial role in surveilling and destroying virally infected or cancerous cells. In controlled experiments, participants engaging in laughter sessions exhibited significantly higher NK cytotoxicity compared to participants watching a neutral video, indicating improved immune surveillance.^[58] In terms of cardiovascular effects, laughter contributes to lowered blood pressure and improved vascular function. Systematic reviews of interventional studies reveal that laughter interventions consistently reduce both systolic and diastolic blood pressure in pre-post measurements, with effects persisting across diverse populations.^[59] This is partly mediated by enhanced endothelial function, where laughter promotes vasodilation through the release of nitric oxide, a potent vasodilator produced by endothelial cells. Research demonstrates that viewing comedic content induces a measurable improvement in flow-mediated dilation, a marker of vascular health, by up to 22%, akin to the effects of moderate physical activity.^[60] Laughter also facilitates pain reduction via endorphin-mediated analgesia. Social laughter triggers the endogenous release of opioids in brain regions like the thalamus and anterior insula, which bind to mu-opioid receptors and elevate pain thresholds. Experimental data indicate that pain tolerance increases significantly following laughter episodes, with effects comparable to those from mild aerobic exercise due to similar endorphin elevations.^[61]^[62] This analgesia is particularly relevant for chronic pain management, as humor-induced endorphin surges help mitigate discomfort without pharmacological intervention.^[63] Regarding mental health, laughter reduces cortisol levels, providing stress relief by counteracting the hypothalamic-pituitary-adrenal axis hyperactivity. Meta-analyses of spontaneous laughter interventions show a substantial 36.7% average reduction in salivary cortisol, outperforming neutral activities and supporting physiological stress recovery.^[64] Furthermore, as an adjunct therapy for depression, laughter-based programs demonstrate efficacy in alleviating symptoms, with randomized controlled trials indicating moderate to large effect sizes in reducing depressive mood when combined with standard treatments. Meta-analyses confirm these benefits, highlighting laughter's role in enhancing emotional regulation and well-being, though effects may vary by population, such as showing no significant impact on depression in nursing students.^[65]^[66] Laughter serves as a key mechanism for signaling affiliation and fostering social bonds within groups, often described as a "social lubricant" that lightens interactions and promotes receptivity among participants.^[5] By facilitating endorphin release during shared laughter, it enhances perceptions of group membership and trust, thereby supporting cooperative behaviors without necessarily extending to prosocial actions toward outsiders.^[67] This function is particularly evident in conversational settings, where laughter punctuates exchanges to build rapport and reinforce in-group cohesion.^[5] The contagious nature of laughter further amplifies its communicative role, spreading through social interactions via neural mechanisms that heighten empathy. Mirror neurons in the auditory-motor system activate when individuals hear laughter, mimicking the emotional response and prompting reciprocal laughter that strengthens interpersonal connections.^[68] This process is linked to emotional contagion, where higher empathy traits correlate with better detection and replication of authentic laughter, facilitating synchronized group responses during conversations.^[69] Such contagion not only synchronizes moods but also builds collective empathy, making laughter a powerful tool for emotional alignment in social contexts.^[26] Gender dynamics influence laughter's signaling patterns, with women typically laughing more frequently than men, especially in mixed-sex interactions, as a cue reflecting power and status hierarchies. In group discussions, women laugh at men's humor at higher rates—up to 71% in some observations—compared to responses to female speakers, signaling deference or alliance in status-driven environments.^[70] This asymmetry underscores laughter's role in navigating social power structures, where it reinforces relational bonds while subtly acknowledging dominance cues.^[71] Across diverse societies, the ability to recognize genuine laughter demonstrates remarkable universality, allowing individuals to discern spontaneous from volitional laughter with accuracies ranging from 56% to 69%, well above chance levels.^[72] This cross-cultural consistency highlights laughter's innate communicative potency, enabling global understanding of authentic affiliation signals regardless of linguistic or cultural barriers.^[73]

Causes and Triggers

Psychological and Emotional Drivers

Laughter often arises from the perception of incongruity, where an unexpected mismatch between expectation and reality is resolved in a non-threatening manner. According to incongruity theory, this resolution triggers amusement by highlighting cognitive dissonance that is ultimately benign, such as in puns or situational ironies where the surprise element dissipates harmlessly.^[74] A modern refinement, the benign violation theory, posits that humor emerges when a situation simultaneously violates norms (creating tension) and appears benign (ensuring safety), explaining laughter at events like awkward accidents or wordplay.^[75] Historically, superiority theory suggested that laughter stems from a sense of triumph over others' misfortunes or shortcomings, as articulated by Thomas Hobbes, who described it as a "sudden glory" arising from recognizing one's superiority.^[76] Similarly, relief theory, advanced by Sigmund Freud, viewed laughter as the release of pent-up psychic energy, particularly from repressed sexual or aggressive impulses, allowing emotional catharsis. Modern critiques argue that superiority theory fails to account for self-deprecating or neutral humor without comparative judgment, rendering it overly narrow for diverse laughter triggers.^[77] Relief theory, meanwhile, is criticized for overemphasizing libidinal tensions and neglecting cognitive or social elements in non-conflictual laughter, such as spontaneous joy.^[78] Psychologically, laughter is elicited by a spectrum of positive emotions, primarily joy and amusement, which activate reward pathways in the brain, but also surprise when it leads to playful resolution rather than alarm.^[79] Additionally, it serves as a mechanism for tension release in states of anxiety or stress, where humorous reframing distances individuals from distress and restores emotional equilibrium.^[80] Individual differences in laughter frequency are linked to personality traits, with extraversion showing a positive correlation, as extraverted individuals exhibit higher rates of laughter and smiling due to greater reward sensitivity and social engagement.^[79] Studies using tools like the Situational Humor Response Questionnaire confirm this association, indicating that extraverts respond more robustly to humorous stimuli across contexts.^[81]

Cultural and Contextual Factors

Laughter's expression and interpretation are profoundly influenced by cultural norms and social contexts, which dictate when and how it is deemed appropriate. In many formal settings, such as professional environments or religious ceremonies, laughter is often suppressed to maintain decorum and focus. For instance, cultural tightness—characterized by strong norms and low tolerance for deviation—has been shown to reduce humor production and laughter in constrained social situations, as individuals prioritize conformity over spontaneous expression.^[82] Similarly, in certain religious traditions, laughter faces taboos rooted in spiritual discipline; early Christian monastic communities, influenced by the Desert Fathers of the 4th century, viewed excessive laughter as a sin that distracted from contemplation, leading to rules enforcing silence and restraint in monastic life.^[83] Cultural variations also manifest in preferred humor styles that elicit laughter, reflecting societal values on communication and interpersonal dynamics. Anglo-Saxon or Anglophone cultures frequently employ sarcasm as a humorous device, where irony and understatement serve to bond groups through subtle critique, differing markedly from other traditions.^[84] In contrast, Japanese humor often relies on puns known as dajare, which exploit phonetic similarities and polysemy for light-hearted wordplay, fostering amusement without direct confrontation and aligning with values of indirectness and harmony.^[85] These styles shape laughter's role: sarcastic humor in Western contexts may provoke knowing chuckles among insiders, while dajare in Japan elicits collective, gentle laughter to reinforce social cohesion. The digital age has amplified media's influence on laughter through comedy formats like memes, which adapt cultural contexts for viral sharing. Studies from the 2020s highlight how memes induce laughter by blending incongruity with relatable scenarios, particularly among younger users; for example, humorous memes on social platforms trigger positive emotional responses and engagement, such as shares and comments, in Generation Z cohorts.^[86] This digital comedy often mirrors cultural nuances, with meme styles varying by region—satirical in individualistic societies and more affiliative in collectivist ones—to evoke context-specific amusement. Gender and age further modulate laughter within these frameworks, influenced by societal expectations. Adolescents, especially in peer groups, exhibit heightened laughter as a tool for bonding and identity formation, with studies showing that middle-schoolers use humor more frequently during interactions to navigate social hierarchies and affirm friendships.^[87] Cross-national surveys reveal variations tied to cultural orientation: in collectivist societies like those in East Asia, laughter tends to emphasize harmony and group affiliation, with individuals laughing more to support relational balance rather than individual wit, contrasting with individualistic cultures where self-enhancing humor prevails.^[88] These patterns underscore how context shapes laughter as a socially adaptive behavior.

Negative Dimensions

Potential Health Risks

While laughter is generally benign, intense or prolonged episodes can occasionally lead to cardiovascular strain in vulnerable individuals. Laughter-induced syncope, a rare form of fainting, occurs due to vasovagal mechanisms where increased intrathoracic pressure from vigorous laughing reduces venous return to the heart, triggering a reflex drop in heart rate and blood pressure.^[89] This phenomenon has been documented in case reports, including a 2025 instance involving a patient with supraventricular tachycardia who experienced syncope during laughter.^[90] More severe events include rare cardiac complications such as arrhythmias or even rupture, as seen in extreme laughing fits that mimic the physiological stress of a Valsalva maneuver.^[91] Additionally, positive emotional triggers like laughter have been linked to takotsubo cardiomyopathy, or "broken heart syndrome," where acute stress causes transient left ventricular dysfunction, as reported in cases of recurrent episodes precipitated by mirth.^[92] Respiratory risks arise primarily in individuals with pre-existing swallowing disorders, or dysphagia, where laughter can disrupt coordinated swallowing and lead to aspiration of food or liquids into the airways. During laughter, the sudden closure of the vocal folds and altered breathing patterns may cause momentary loss of airway protection, increasing the chance of pulmonary aspiration and subsequent pneumonia in at-risk patients. Clinical guidelines recommend avoiding laughter or talking during meals for those with dysphagia to mitigate this hazard.^[93] Musculoskeletal strain from laughter typically manifests as transient discomfort, such as side stitches—sharp pains in the abdomen or flank—resulting from diaphragm spasms or irritation of the peritoneal lining during repetitive contractions. Prolonged laughing can also induce jaw fatigue or pain, particularly in those with temporomandibular joint (TMJ) disorders, where sustained mouth opening and facial muscle engagement exacerbate soreness or spasms. Case studies, including reports from 2022, highlight laughter as a potential migraine trigger in susceptible individuals, possibly due to transient vascular changes like cerebral blood flow alterations during the physiological response. Case studies describe "laugh headaches," reproducible episodes of severe head pain immediately following intense laughter, often resembling migraine auras or attacks without structural abnormalities on imaging.^[94] These events underscore the need for caution in migraine-prone patients during social situations involving humor. Derisive laughter, characterized by mockery and ridicule, serves as a tool for bullying that reinforces social hierarchies and leads to exclusion. In interpersonal dynamics, such laughter amplifies the emotional impact of insults, making victims feel more humiliated and isolated within groups. For instance, research demonstrates that the presence of an audience laughing in response to an insult prolongs and intensifies negative emotional processing in the brain, heightening perceptions of rejection and vulnerability.^[95] This form of laughter not only signals derision but also cues social exclusion, triggering physiological responses akin to rejection, such as heart rate deceleration indicative of a "freezing" state in affected individuals.^[96] Consequently, repeated exposure to derisive laughter in bullying contexts fosters long-term social withdrawal and diminished self-esteem among targets.^[97] Nervous laughter often emerges as an involuntary response to mask underlying discomfort, tension, or fear in awkward social situations. While it functions as a short-term defense mechanism to diffuse anxiety by discharging emotional energy, this avoidance strategy can inadvertently exacerbate the underlying distress over time. By suppressing genuine emotional expression, nervous laughter prevents resolution of the discomfort, potentially reinforcing cycles of heightened anxiety and social unease in future interactions.^[98] Studies suggest that such laughter ties into broader patterns of emotional dysregulation, where individuals struggling with anxiety use it to cope but find it hinders deeper self-awareness and relational authenticity.^[99] Inappropriate laughter in solemn or sensitive contexts, such as funerals or discussions of tragedy, can provoke offense and erode social bonds due to its misalignment with expected emotional norms. Laughter's meaning is profoundly context-dependent; when it occurs amid gravity, it may be interpreted as insensitivity or mockery, leading to interpersonal conflict or exclusion from the group. Cultural variations further complicate this, as what one society views as a neutral release of tension might be seen as disrespectful in another, amplifying relational discord.^[100] For example, unreciprocated or untimely laughter disrupts shared emotional synchronization, fostering resentment and perceptions of emotional ineptitude.^[101] Gelotophobia, defined as the pervasive fear of being laughed at, represents a significant psychological drawback, manifesting as hypervigilance to potential ridicule and avoidance of social settings involving humor. This condition, assessed via scales like GELOPH<15>, affects approximately 10-20% of individuals in population surveys, with higher rates in certain cultures such as the UK (around 14%).^[102] It stems from early experiences of mockery or bullying, leading to misinterpretation of neutral laughter as derisive, which perpetuates anxiety, low self-esteem, and social isolation.^[103] Affected individuals often exhibit elevated trait anxiety and reduced life satisfaction, underscoring gelotophobia's role in impairing interpersonal trust and emotional well-being.^[104]

Therapeutic and Applied Uses

Laughter Therapy Techniques

Laughter yoga, developed by Indian physician Madan Kataria in 1995, is a structured practice that induces laughter through simulated exercises rather than relying on humor or jokes.^[105] The protocol typically begins with warm-up activities such as rhythmic clapping, chanting "ho ho ha ha ha," and deep breathing exercises to prepare participants physically and mentally.^[106] Participants then engage in a series of simulated laughter exercises, including "milk shaking" (pretending to shake milk until it turns into butter while laughing) and "lion laughter" (sticking out the tongue and roaring with laughter), often performed in pairs or groups to foster interaction.^[107] These exercises combine elements of yoga, like pranayama breathing, with childlike playfulness, gradually transitioning simulated laughter into genuine outbursts through prolonged physical simulation.^[108] Clown therapy, also known as medical clowning, employs professional clowns trained in therapeutic techniques to deliver humor in hospital environments, particularly for pediatric patients.^[109] Key methods include improv games such as spontaneous role-playing scenarios, where clowns interact with children using exaggerated facial expressions, props, and absurd storytelling to elicit laughter and distraction from medical procedures.^[110] Techniques emphasize non-verbal communication, like mirroring patient movements or creating playful "magic" tricks with everyday objects, to build rapport and reduce anxiety without requiring verbal responses.^[111] Sessions are typically short, lasting 10-20 minutes per patient interaction, and are conducted by pairs of clowns to enhance dynamic improvisation.^[112] Group laughter therapy sessions, often modeled after laughter yoga protocols, are formatted to last 20-30 minutes and prioritize collective engagement to amplify the therapeutic effect.^[107] Participants form circles to maintain eye contact, which promotes trust and vulnerability, while incorporating synchronized breathing exercises like alternate nostril breathing to regulate oxygen intake and sustain laughter.^[108] The structure includes an initial warm-up with gentle stretches and clapping, followed by 15-20 minutes of laughter exercises, and concludes with relaxation techniques such as laughter meditation, where participants lie down and allow residual giggles to subside naturally.^[113] Evidence-based adaptations of laughter therapy have incorporated virtual reality (VR) since the early 2020s to enable remote or individualized induction. One such program, the Embodied Laugh Track system developed in 2025, immerses users in a virtual theater with simulated audiences that respond to comedy with multimodal laughter cues, including audio and haptic feedback, to trigger genuine laughter.^[114] Another example is a 2021 mobile VR self-management program for postpartum women, which integrates laughter therapy modules with guided exercises viewed through headsets, demonstrating feasibility for home-based use.^[115] These VR tools adapt traditional techniques by using interactive avatars and biofeedback to personalize laughter prompts, ensuring accessibility for those unable to attend in-person sessions.^[114]

Clinical and Wellness Applications

In dementia care, particularly for patients with Alzheimer's disease, humor-based interventions have demonstrated efficacy in reducing agitation through randomized controlled trials (RCTs). The Sydney Multisite Intervention of LaughterBosses and ElderClowns (SMILE) study, a cluster RCT involving 189 nursing home residents with dementia, found that weekly sessions with professional humorists—such as clowns and comedians—resulted in a 20% reduction in agitation behaviors compared to standard care, an effect comparable to antipsychotic medications without their side effects.^[116] This improvement was measured using the Cohen-Mansfield Agitation Inventory, highlighting laughter's role as a non-pharmacological option to manage behavioral symptoms in long-term care settings.^[117] For cancer support, group laughter therapy has shown promise in alleviating chemotherapy-related side effects. An RCT of 60 patients with gynecological cancer undergoing chemotherapy revealed that a structured laughter yoga program, conducted in groups for 20-30 minutes weekly over eight weeks, significantly reduced nausea severity and overall symptom burden, with participants reporting lower Rhodes Index of Nausea scores post-intervention.^[118] Similarly, another RCT involving cancer patients (majority with breast cancer) demonstrated that laughter yoga sessions decreased pain intensity and fatigue during treatment cycles, improving health-related quality of life as assessed by standardized scales like the EORTC QLQ-C30.^[119] These findings support the integration of group-based laughter into oncology care to mitigate treatment toxicities. Workplace wellness programs incorporating laughter have been linked to reduced burnout and enhanced productivity, as evidenced by recent studies. A 2022 RCT on 101 nurses found that eight weeks of laughter yoga sessions lowered burnout scores by approximately 21% on the Maslach Burnout Inventory, alongside decreased perceived stress.^[120] Broader evidence from a 2012 meta-analysis of positive humor in the workplace confirmed that it is associated with enhanced work performance, satisfaction, and coping effectiveness, while mitigating stress across professions.^[121] These programs, often delivered via short group sessions, foster resilience in high-stress environments like healthcare. Despite these outcomes, clinical applications of laughter face limitations, including the scarcity of long-term longitudinal studies tracking sustained effects beyond 12 weeks and insufficient representation of diverse populations, such as ethnic minorities or low-income groups, as highlighted in systematic reviews.^[122] Future research should prioritize larger, multi-site RCTs to address these gaps and validate generalizability.^[119]

Historical and Philosophical Explorations

Ancient Views and Thinkers

In ancient Greek philosophy, Plato expressed ambivalence toward laughter, viewing it as potentially beneficial but often harmful when excessive. In the Republic, he cautioned against allowing guardians to indulge in uncontrolled laughter, arguing that it leads to a loss of self-control and undermines the soul's rational order, likening it to a violent emotional upheaval that disrupts harmony.^[123] In the Philebus, Plato further analyzed laughter as a form of scornful pleasure, arising from the perception of others' ignorance or misfortune, which mixes pain with delight and can foster malice rather than virtue.^[124] Aristotle, building on such ideas, regarded laughter as a distinctive human trait that elevated civilization. In History of Animals, he observed that humans alone among creatures laugh, attributing this to the capacity for reflective emotion and physiological differences such as the structure of the heart and respiratory system that enable such responses, setting humanity apart from animals in a way that underscores rational and social sophistication.^[125] In the Poetics, he positioned laughter within comedy as an imitation of human flaws, portraying it as a civilized art form that invites gentle ridicule of the worse aspects of character without descending into vulgarity.^[125] Herodotus incorporated laughter into his historical narratives to illustrate cultural clashes and divine retribution. In the Histories, he recounted how the Persian king Cambyses mocked and laughed at the sacred Egyptian Apis bull during a ritual, wounding the animal in derision and questioning the divinity of such fleshly forms, an act the Egyptians interpreted as inviting madness and eventual punishment from the gods.^[126] Similarly, the Ethiopian king laughed at Persian envoys' jewelry, mistaking it for feeble restraints, highlighting laughter's role in underscoring ritual superiority and foreign misunderstandings.^[126] Biblical perspectives emphasized the timeliness of laughter as part of divine order. The Book of Proverbs advises that a cheerful disposition, akin to timely laughter, acts as medicine for the soul, promoting health while a broken spirit withers it.^[127] Ecclesiastes reinforces this by declaring a season for laughter amid life's rhythms, balanced against weeping and mourning to reflect wisdom in moderation.^[128] In Eastern thought, Confucian teachings promoted restraint in laughter to uphold social decorum. The Analects describe the ideal gentleman as one who laughs only when genuinely happy, ensuring his mirth remains measured and endearing without excess, thus preserving dignity and harmony in interactions. This approach contrasts with unchecked expression, aligning laughter with ritual propriety rather than impulsive emotion.^[129]

Modern Theories and Researchers

In the 17th century, English philosopher Thomas Hobbes articulated one of the earliest modern theories of laughter, framing it as an expression of "sudden glory" derived from a perceived superiority over others. In his treatise Human Nature (1650), Hobbes defined laughter as "nothing else but sudden glory arising from some sudden conception of some eminency in ourselves, by comparison with the infirmity of others, or with our own formerly," positioning it as a fleeting recognition of personal advantage that underscores human competitiveness and social hierarchy.^[130] This superiority theory, elaborated further in Leviathan (1651), portrayed laughter not merely as amusement but as a manifestation of power dynamics, influencing subsequent philosophical and psychological interpretations of humor as a tool for self-affirmation amid vulnerability.^[131] Hobbes's view marked a shift from earlier moralistic accounts, emphasizing laughter's mechanistic and egoistic roots in post-Enlightenment thought.^[76] Building on such foundations, French philosopher Henri Bergson offered a contrasting perspective in Laughter: An Essay on the Meaning of the Comic (1900), where he theorized laughter as a response to "mechanical inelasticity" in human behavior. Bergson contended that comedy emerges when vital, flexible life encounters rigidity—like a person's actions mimicking a machine's automatism—failing to adapt to fluid social or physical contexts, and laughter acts as a societal corrective to restore elasticity and vitality.^[132] He illustrated this through examples of repetitive gestures or social faux pas, arguing that such inelasticity disrupts the expected harmony of living organisms, prompting detached, corrective mirth to enforce communal norms without direct confrontation.^[133] Bergson's framework, emphasizing laughter's role in humanizing the mechanical, has enduringly shaped humor studies by highlighting its corrective function in modern, industrialized societies.^[134] Friedrich Nietzsche extended these ideas into a metaphysical dichotomy in works such as The Birth of Tragedy (1872) and later writings, contrasting Dionysian laughter as ecstatic release with Apollonian restraint. For Nietzsche, Dionysian laughter embodies uninhibited joy and dissolution of the self, a vital affirmation of life's chaos and suffering through exuberant, boundary-dissolving exuberance, as seen in the revelry of ancient Greek rites.^[135] In opposition, Apollonian elements impose form, individuation, and sober illusion, tempering laughter's wildness to channel it into structured art or philosophy, preventing total anarchy.^[136] This duality positions laughter as a bridge between instinctual excess and rational order, essential for cultural vitality and personal overcoming, with Nietzsche advocating its Dionysian form as a counter to nihilistic resignation.^[137] Immanuel Kant, in Critique of Judgment (1790), proposed that laughter arises from the sudden transformation of a strained expectation into nothing, highlighting the play between imagination and understanding. Arthur Schopenhauer further developed the incongruity theory, arguing in The World as Will and Representation (1818) that laughter results from the frustration of a concept by reality, revealing the inadequacies of abstract thought.^[138] The 20th century saw significant empirical advancements in the scientific study of laughter, known as gelotology, with psychologist Willibald Ruch contributing foundational models from the 1990s. Ruch's work, including his research on humor appreciation styles (e.g., affiliative vs. aggressive) and temperamental dispositions like cheerfulness, differentiated laughter from smiling and explored its role in emotional contagion, cognitive processing, and social bonding.^[139]^[140] This approach bridged earlier theories, such as Hobbes's superiority and Bergson's social correction, with measurable outcomes in human behavior. In the 2020s, gelotological insights have converged with positive psychology, theorizing laughter as a key enhancer of resilience by buffering stress and amplifying adaptive coping. Researchers have demonstrated that interventions promoting laughter, such as structured exercises, elevate positive affect and emotional regulation, fostering resilience in high-stress contexts like healthcare during pandemics.^[141] For instance, laughter therapy has been shown to mitigate anxiety and bolster psychological fortitude, aligning with positive psychology's emphasis on strengths like optimism to counteract adversity.^[142] This integration reframes laughter not just as reactive mirth but as a proactive mechanism for building enduring well-being, extending Nietzsche's Dionysian release into evidence-based practices for modern mental health. Feminist critiques have illuminated the gendered underpinnings of laughter, revealing how theories like superiority and inelasticity often overlook patriarchal biases in its expression and reception. Scholars argue that women's laughter is disproportionately scrutinized or weaponized, reinforcing stereotypes of hysteria or frivolity, while male laughter asserts dominance unchecked.^[143] For example, Hélène Cixous's écriture féminine posits laughter as a subversive, bodily revolt against phallocentric restraint, disrupting linear, Apollonian narratives with joyful excess akin to Dionysian liberation.^[144] These analyses extend Bergson's social corrective to critique how gendered laughter perpetuates inequality, yet also empowers resistance through ironic or collective humor that challenges norms.^[145] Emerging 2020s research on AI-generated humor probes laughter's philosophical mechanics through computational lenses, testing whether machines can replicate superiority, inelasticity, or Dionysian elements. Studies find AI capable of crafting jokes eliciting laughter comparable to human efforts in controlled settings, such as meme creation, but faltering on contextual nuance and emotional depth.^[146] This work highlights gaps in AI's grasp of laughter's social elasticity, as theorized by Bergson, and its resilient, affirmative role in positive psychology, suggesting hybrid human-AI models may enrich future gelotological theories.^[147]

References

[1]
Pathological laughter. A review of the literature - PubMed
Normal laughter is a unique human behavior with characteristic facial and respiratory patterns elicited by a variety of stimulus conditions.
[2]
The social life of laughter - PMC - PubMed Central
Laughter is characterized by very rapid contractions of the intercostal muscles, resulting in large exhalations followed by individual bursts of laughter: the ...
[3]
Stress relief from laughter? It's no joke - Mayo Clinic
Laughter enhances your intake of oxygen-rich air, stimulates your heart, lungs and muscles, and increases the endorphins that are released by your brain.Missing: definition | Show results with:definition
[4]
The Laughter Prescription: A Tool for Lifestyle Medicine - PMC - NIH
Abstract. Laughter is a normal and natural physiologic response to certain stimuli with widely acknowledged psychological benefits.
[5]
Laughter therapy: A humor-induced hormonal intervention to reduce ...
Laughter therapy can physiologically lessen the pro-stress factors and increase the mood-elevating anti-stress factors to reduce anxiety and depression.<|separator|>
[6]
THE EVOLUTION AND FUNCTIONS OF LAUGHTER AND HUMOR
We consider laughter to have been a preadaptation that was gradually elaborated and co‐opted through both biological and cultural evolution. We hypothesize that ...
[7]
Laughter and its role in the evolution of human social bonding
Sep 21, 2022 · Laughter, a form of chorusing, evolved to increase social bonding by triggering the endorphin system, likely with early Homo, when group size ...
[8]
Shared Laughter as Behavioral Indicator of Relationship Well-Being
Laughter is a pervasive human behavior that most frequently happens in a social context. However, data linking the behavior of laughter with psychological or ...
[9]
The Complexity and Phylogenetic Continuity of Laughter and Smiles ...
Activations of orbicularis oculi raise the cheeks, causing the wrinkling around the eye corners, i.e., crow's feet, which characterizes Duchenne laughter/ ...
[10]
[PDF] The deliberate Duchenne smile: perceptions and social outcomes.
Jun 7, 2013 · The Duchenne smile, which is a smile that involves activation of the cheek raiser muscle that creates crow's feet around the eyes, ...
[11]
'Should we laugh?' Acoustic features of (in)voluntary laughters in ...
Nov 23, 2023 · Laughter was acoustically characterised by Provine (1996) as follows: short vowel-like notes (75 ms long in general), which were recurred ...
[12]
[PDF] ACOUSTIC ANALYSIS OF LAUGHTER - LabROSA
The range of FO was observed to be 100 to 155 Hz for the mil speaker with an average value of 138 Hz; for the female speak the range was 161 to 476 Hz with an ...
[13]
An acoustic analysis of laughter produced by congenitally deaf and ...
An unvoiced sound was one containing 25% or less voicing, mixed sounds contained between 25% and 75% voicing, and voiced sounds had 75% or more voicing.
[14]
Respiratory dynamics during laughter - ResearchGate
Aug 10, 2025 · laughter is produced by a deep inspiration followed by short, interrupted, spasmodic contractions of the chest, and especially of the diaphragm.
[15]
[PDF] Rhythmic Body Movements of Laughter
Nov 16, 2014 · Body movements are important markers allowing distinguishing laughter from smiling (be- sides facial and vocal expressions). The presence of ...
[16]
[PDF] On Laughter Intensity Level: Analysis and Estimation - ISCA Archive
This work focuses on laughter intensity level, the way it is perceived and suggests ways to estimate it automatically. In the first part of this paper, ...<|separator|>
[17]
Laughter and its role in the evolution of human social bonding - PMC
Sep 21, 2022 · I show, first, that human laughter both upregulates the brain's endorphin system and increases the sense of bonding between those who laugh together.Missing: exaggerated | Show results with:exaggerated
[18]
Different types of laughter and their function for emotion regulation in ...
Aug 4, 2022 · Spontaneous laughter is an impulsive, uncontrolled laughing reaction. The voluntary type, on the other hand, is an artificial expression and the ...
[19]
Classification of social laughter in natural conversational speech
Various types of laughter were categorized into either polite or genuinely mirthful categories and the analysis of these laughs forms the core of this report.
[20]
[PDF] CLASSIFYING LAUGHTER - University of Pennsylvania
1. Individuals can classify instances of laughter by type. 2. Affiliative, de-escalative, and power laughter differ in the following acoustic properties: ...
[21]
The different shades of laughter: when do we laugh and when ... - NIH
Sep 21, 2022 · Shared laughter signals a shared understanding of the situation and ultimately trust [9]. At the same time, laughing at someone degrades that ...
[22]
differences in emotional arousal level between the East and the West
Westerners value, promote, and experience high arousal emotions more than low arousal emotions, whereas the vice versa is true for Easterners.
[23]
To Be or Not To Be Humorous? Cross Cultural Perspectives on Humor
Oct 4, 2016 · The authors suggest that Westerners regard humor as a common and positive disposition; the Chinese regard humor as a special disposition ...
[24]
Laughing Matters: Infant Humor in the Context of Parental Affect - PMC
By 7 months, infants smiled and laughed more often and sooner when their parents cued them than when they remained neutral. Thus generally speaking, the social- ...
[25]
Pseudobulbar affect - Symptoms and causes - Mayo Clinic
May 16, 2018 · Pseudobulbar affect (PBA) is a condition that's characterized by episodes of sudden uncontrollable and inappropriate laughing or crying.
[26]
Motor and Limbic System Contribution to Emotional Laughter across ...
May 14, 2020 · We characterized the neural correlates of emotional laughter using the onsets and the duration of laughter bursts to inform functional magnetic resonance ...Missing: EEG studies
[27]
Laughter is in the air: involvement of key nodes of the emotional ...
An involvement of the lateral hypothalamus in human laughter was first suggested by findings in pathological situations (Martin, 1950), relating, in particular ...
[28]
Humor modulates the mesolimbic reward centers - PubMed - NIH
We present new evidence that humor engages a network of subcortical regions including the nucleus accumbens, a key component of the mesolimbic dopaminergic ...Missing: laughter | Show results with:laughter
[29]
Modality-Specific Contagion of Laughter and Yawning in the ... - NIH
Feb 17, 2022 · Interestingly, the auditory mirror neuron system in particular contributes to contagious laughter (Billing et al., 2021), which can be an ...
[30]
Social Smiling and Laughter Are Linked to Enhanced Functional ...
Sep 25, 2025 · Neuroimaging results showed that on average infants displayed greater functional connectivity in the right than in the left hemisphere of the ...
[31]
Hemispheric asymmetry in the expression of positive and ... - PubMed
Pathological laughing was associated with predominantly right-sided damage, whereas pathological crying was associated with predominantly left-sided lesions. In ...
[32]
Respiratory dynamics during laughter - PubMed
We conclude that fits of laughter consistently lead to sudden and substantial decrease in lung volume in all respiratory compartments and remarkable dynamic ...
[33]
The Health Implications of Laughter: From Ab Workouts to Stress ...
Dec 11, 2023 · Laughter causes the diaphragm, chest and abdominal muscles to tighten, driving the lungs to work harder through forcing the remaining air ...
[34]
Anatomy, Head and Neck: Facial Muscles - StatPearls - NCBI - NIH
Apr 20, 2024 · Notably, the orbicularis oculi and zygomaticus major are the fastest-moving muscles in the human body. .[10]. Go to: Embryology. The facial ...
[35]
Laugh your abs off - AP News
Oct 27, 2018 · When we laugh, our diaphragm, internal obliques and transverse abdominis, which is the deepest abdominal muscle, contract and force air up into ...
[36]
The Physiological Effects of Laughter - Find a Psychologist
Similar to aerobic exercise, a hearty laugh involves contraction and relaxation of facial, chest, abdominal and skeletal muscles, easing muscle tension and ...
[37]
Analysis of production characteristics of laughter - ScienceDirect.com
In the current study, we examine changes in the glottal excitation source characteristics and associated changes in the vocal tract system characteristics, ...
[38]
Social Laughter Triggers Endogenous Opioid Release in Humans
Social laughter releases immunoenhancers (such as β-endorphins), but it also increases the activity of natural killer cells (lymphocytes) and lowers cortisol ...
[39]
Finding humor in hormones: Oxytocin promotes laughing and smiling
Jun 3, 2022 · In this study, we investigated whether OT would increase laughing and smiling in a favorable environment.
[40]
The evolution of laughter in great apes and humans - PMC - NIH
It has long been claimed that human emotional expressions, such as laughter, have evolved from nonhuman displays.
[41]
The evolutionary origins of laughter are rooted more in survival than ...
Apr 13, 2016 · Laughter probably evolved from laboured breathing during play such as tickling, which encourage cooperative and competitive behaviour in young mammals.
[42]
The Search for Laughter's Evolutionary Origins | Psychology Today
May 30, 2023 · A comprehensive theory to explain why we laugh must provide a meaningful account of its origins. Can we learn about its meaning or purpose ...
[43]
[PDF] Evolution, Structure, and Functions of Human Laughter
Laughter is a nonverbal vocalization with rhythmic respiratory and laryngeal activity, involving air forced through the glottis, and rapid opening/closing of ...
[44]
The Evolution of the Primal Defense Mechanism Called Laughter
Jul 20, 2009 · Laughter is ancient, predating the development of language. It's ubiquitous; all mammals do it, panting with delight in response to tickling or ...
[45]
What's the point of laughter? - BBC Science Focus Magazine
Her work suggests that laughter arose from a common primate ancestor millions of years ago – long before language evolved. Why does tickling make us laugh?
[46]
Evolution of laughter from play - PMC - NIH
Apr 8, 2024 · In this hypothesis, I discuss how laughter from physical play could have evolved to being induced via visual or even verbal stimuli, ...
[47]
Chimpanzees (Pan troglodytes) Produce the Same Types of 'Laugh ...
Jun 10, 2015 · The results on chimpanzee open-mouth faces and laughter revealed substantial commonalities with humans. The chimpanzees showed altogether 14 ...
[48]
Laughter, play faces and mimicry in animals: evolution and social ...
Sep 21, 2022 · Phylogenetic research on hominids provided empirical evidence on shared ancestry across these emotional expressions, including human laughter ...Missing: post- | Show results with:post-
[49]
When Apes Laugh, They Offer a Window Into Human Evolution
Jun 30, 2023 · All the great apes use a breathy, chuckling, panting laughter during rough-and-tumble play and play chases. They are especially fond of tickling ...
[50]
Human Laughter Echoes Chimp Chuckles - WIRED
Jun 4, 2009 · ... breath, and that bonobo laughter involved vibrations of the vocal cords. Previous work also found vocal cord vibrations during chimp laughter.
[51]
effects of social housing and genetic variables - PubMed
50-kHz chirping (laughter?) in response to conditioned and unconditioned tickle-induced reward in rats: effects of social housing and genetic variables.
[52]
Tickling increases dopamine release in the nucleus accumbens and ...
Mar 27, 2013 · Our study demonstrates that tickling stimulation in adolescent rats increases dopamine release in the nucleus accumbens, leading to the generation of 50 kHz ...
[53]
α- and β-Adrenergic Receptors Differentially Modulate the Emission ...
Oct 26, 2011 · Reduction of dopamine synaptic activity: degradation of 50-kHz ultrasonic vocalization in rats. ... 50-kHz chirping (laughter?) in response ...
[54]
[PDF] Dogs Produce Distinctive Play Pants: Confirming Simonet et al. (2001)
behaviors (e.g., play bow) or tickling and cuddling. These preliminary findings suggest that a laugh-like play pant is used by dogs during play; future ...
[55]
Dog 'laugh' silences other dogs - Phys.org
Dec 5, 2005 · The scientists say the long, loud pant they recorded has a calming or soothing effect on the behavior of other dogs, ABC News reported. Nancy ...
[56]
An Acoustic Play-Fight Signal in Bottlenose Dolphins (Tursiops ...
Aug 6, 2025 · (2005) found that play-fighting dolphins typically emitted a short burst pulse combined with a whistle, acoustically different from aggressive ...
[57]
What are animals saying? AI may help decode their languages
Oct 15, 2024 · A groundbreaking research project is finally building the tools to translate just how whales and other creatures communicate.Missing: laughter 2023
[58]
How Scientists Started to Decode Birdsong | The New Yorker
Oct 14, 2024 · Language is said to make us human. But, as Rivka Galchen writes, some ornithologists and bird-watchers believe that birds talk, too.
[59]
maja białek * the new anthropomorphism debate and researching ...
Oct 2, 2023 · Researchers of non-human animal emotions tend to defend some forms of anthropomorphism and seek ways to make it more critical, self-aware, ...
[60]
Humor and Laughter May Influence Health IV. Humor and Immune ...
Dec 5, 2007 · Natural killer (NK) cells are lymphocytes which are classified as a non-B, non-T or null cells. NK cells are able to lyze tumor cell line in ...
[61]
The effect of mirthful laughter on stress and natural killer cell activity
... laughter (Humor Response Scale), and immune function (chromium release natural killer [NK] cell cytotoxicity assay). Results: Stress decreased for subjects ...Missing: IgA antibodies
[62]
Impact of cinematic viewing on endothelial function - PMC - NIH
The present study was designed to compare the effect of mental stress versus laughter on endothelial function.
[63]
Social Laughter Triggers Endogenous Opioid Release in Humans
Jun 21, 2017 · Social laughter increased pleasurable sensations and triggered endogenous opioid release in thalamus, caudate nucleus, and anterior insula.
[64]
Social laughter is correlated with an elevated pain threshold - PMC
Sep 14, 2011 · Another possibility is that laughter plays a more generalized role in social bonding at the group level [2], thereby facilitating the enhanced ...Missing: displays | Show results with:displays<|control11|><|separator|>
[65]
Humor Therapy: Relieving Chronic Pain and Enhancing Happiness ...
The use of humor consistently results in improvements in pain thresholds [29]. Humor also leads to the release of endorphins in the brain, which help to control ...
[66]
Laughter as medicine: A systematic review and meta-analysis of ...
May 23, 2023 · Current evidence demonstrates that spontaneous laughter is associated with greater reduction in cortisol levels as compared with usual activities.Missing: 2020-2025 | Show results with:2020-2025<|control11|><|separator|>
[67]
A meta‐analysis of randomized controlled trials of laughter and ...
May 23, 2025 · Conclusions This meta‐analysis revealed that laughter and humour interventions are effective in relieving depression, anxiety, and improve sleep ...
[68]
The Effectiveness of Laughter-Based Interventions on Psychological ...
Aug 12, 2025 · This comprehensive systematic review and meta-analysis examined the effects of laughter-based interventions on psychological, physiological and ...Missing: relief | Show results with:relief
[69]
Laughter influences social bonding but not prosocial generosity to ...
Aug 13, 2021 · We show that laughter does trigger the endorphin system and, through that, seems to enhance social bonding, but it does not reliably influence donations to ...Missing: lubricant | Show results with:lubricant
[70]
Positive Emotions Preferentially Engage an Auditory–Motor “Mirror ...
Dec 13, 2006 · Our findings demonstrate that listening to nonverbal vocalizations can automatically engage preparation of responsive orofacial gestures.Auditory Stimuli · Fmri Data Analysis · Fmri StudyMissing: contagion | Show results with:contagion<|separator|>
[71]
High emotional contagion and empathy are associated with ...
To conclude, the current study identified for the first time a link between higher trait levels of emotional contagion and empathy and enhanced ability to ...
[72]
Laughter Punctuates Speech: Linguistic, Social and Gender ...
Audiences of both males and females laughed more to male than female speakers. These baseline data provide insights into gender differences, normal and ...
[73]
[PDF] Getting A Laugh: Gender, Status, and Humor in Task Discussions*
Women laugh more than men in group conversations (Dovidio et al. 1988,. Dovidio & Ellyson 1982) as well as display lower levels of nonverbal dominance ...
[74]
https://journals.sagepub.com/doi/abs/10.1177/0956797610376073
[75]
The Perception of Spontaneous and Volitional Laughter Across 21 ...
Here, we examined whether listeners around the world, irrespective of their own native language and culture, can distinguish between spontaneous laughter and ...
[76]
Benign Violations: Making Immoral Behavior Funny - Sage Journals
Five experimental studies show that benign moral violations tend to elicit laughter and amusement in addition to disgust.
[77]
[PDF] Benign Violations: Making Immoral Behavior Funny
We tested the benign-violation hypothesis by examining reac- tions to moral violations, or behaviors people consider wrong. Moral violations provide a ...
[78]
The Place of Laughter in Hobbes's Theory of Emotions - jstor
It is important to note that Hobbes's superiority theory of laughter com- pletely dissociates laughter from its most apparent source, the comic ("wit" and ...
[79]
[PDF] Superiority in Humor Theory - Bucknell Digital Commons
Thus, Hobbes believes there is more to laughter than superiority and appears to hold a theory of laughter that places novelty and incongruity in a central ...
[80]
[PDF] Philosophy of Humour and Laughter – a critical analysis
The second theory was the relief theory by. Freud. Freud posited that laughter came about from an excess of energy that had no other way of being released ...
[81]
Personality predicts activity in reward and emotional regions ... - PNAS
Nov 7, 2005 · Both empirical and anecdotal observations point to extroverts as having a higher frequency of laughter, smiling, feelings of subjective well- ...Missing: extraversion | Show results with:extraversion
[82]
[PDF] Distinct Correlates of Laughter and Smiling During Bereavement
Laughter facilitates the adaptive response to stress by increasing the psychological distance from distress and by enhancing social relations.
[83]
An analysis of the Situational Humor Response Questionnaire (SHRQ
This study was an attempt to determine whether the degree of laughing in a variety of situations is related to Extraversion.
[84]
Cultural tightness reduces humor production: Evidence from multiple ...
Oct 16, 2025 · Studies 5a (N = 233) and 5b (N = 246) with priming found that cultural tightness hindered humor production. Drawing on cross-cultural evidence, ...
[85]
Religions with or without Sense of Humor: A Psychological ... - MDPI
But laughter is viewed as a sin in the 4th century by Desert Fathers in the early Church history (Smith 1931). The source were friars, instructor monks that ...
[86]
The English classroom as “warai no ba”: Instructor views on humor ...
While sarcasm certainly exists in the Japanese language, the frequency and purpose differ from the sarcasm of anglophone cultures (Okamoto, 2007). And although ...
[87]
(PDF) Japanese Puns Are Not Necessarily Jokes - ResearchGate
In this paper we describe a phonetic classification of Japanese puns (dajare). Basing on real life examples gathered from available sources (books, Internet), ...Missing: styles | Show results with:styles
[88]
Psycho-physiological impact of virtual non-verbal communication on ...
This study is perhaps the first of its kind to examine the gender-based psycho-physiological impact of memes as virtual nonverbal communication, on Gen Z.
[89]
Adolescent Humor During Peer Interaction - jstor
Humor serves a number of purposes in interaction among adolescent friends. A study of predominantly female peer groups in a middle-school setting revealed ...
[90]
Cultural Differences in Humor Perception, Usage, and Implications
The aim of this article provides a review of how culture influences humor perception and usage as well as the relationship between humor and psychological well ...
[91]
Laughter-induced syncope - PMC - NIH
Laughter-induced syncope is a rare entity and is thought to be caused by vasovagal mechanisms. The increase in intrathoracic pressure reduces venous return to ...
[92]
A Case of Laughing‐Induced Syncope and a Review of the Literature
Oct 15, 2025 · This case highlights a unique presentation of laughter‐induced syncope in a patient with a history of supraventricular tachycardia (SVT), ...Missing: events attack fainting
[93]
Laughter and MIRTH (Methodical Investigation of Risibility ...
Dec 12, 2013 · Laughter in Angelman's (“happy puppet”) syndrome can cause asystolic arrest, apparently of vagal origin. Laughing fit to burst can cause cardiac ...Missing: events fainting
[94]
(PDF) The idiom, laughter is the best medicine is not always true ...
The idiom, laughter is the best medicine is not always true. Takotsubo Cardiomyopathy precipitated by positive emotion, recurrence in the patient.
[95]
Aspiration Pneumonia - StatPearls - NCBI Bookshelf - NIH
Mar 20, 2024 · The common risk factors associated with aspiration pneumonia include advanced age, dysphagia, altered mental status, neurological disorders, and ...Aspiration Pneumonia · Evaluation · Treatment / ManagementMissing: laughter | Show results with:laughter<|control11|><|separator|>
[96]
Aspiration pneumonia: Treatment, complications, and outlook
Several conditions are associated with dysphagia and increase a person's risk of developing aspiration pneumonia. ... avoiding laughing or talking while eating ...
[97]
TMJ Disorders: Symptoms & Treatment - Cleveland Clinic
TMD causes jaw pain, headaches and trouble chewing. It's common and treatable with therapies that ease pain and improve jaw function.Jaw Pain · Jaw popping · Otolaryngologist · MalocclusionMissing: fatigue laughter
[98]
Laugh Headache, Not a Joke! A Case Report - PMC - NIH
Feb 15, 2022 · We present a case of a young student whose laughing aloud is a potent headache precipitant and is consistently reproducible despite normal brain imaging.Missing: jaw fatigue
[99]
Full article: No laughing matter: How the presence of laughing ...
The presence of a laughing crowd has a direct effect on the neurocognitive processing of insults, leading to stronger and more elongated emotional processing.
[100]
Laughter as a social rejection cue: Gelotophobia and transient ...
Jul 1, 2014 · They fear the laughter of other persons and are hypervigilant toward signs of derision and persons that might ridicule them (Ruch, Hofmann, ...
[101]
Excluded by laughter: laughing until it hurts someone else - PubMed
Given the host of ways exclusion is communicated, we examined if exclusive laughter could produce the aversive consequences accordant with social exclusion.Missing: derisive research paper
[102]
Why We Laugh When We're Nervous | Psychology Today
Aug 4, 2021 · Nervous laughter can be viewed as a defense mechanism subconsciously employed to protect one from feeling overwhelmed with anxiety.
[103]
Nervous Laughter Explained | Walden University
Psychologists agree that nervous laughter is the body's way of dealing with stress, anxiety, or overwhelming emotions that the mind is struggling to process.
[104]
Why do we laugh inappropriately? - BBC
Mar 22, 2015 · We often find ourselves laughing in the strangest situations, revealing the profound nature of this odd human behaviour.
[105]
Inappropriate laughter: Causes, treatments, and coping strategies
Feb 11, 2022 · Inappropriate or uncontrollable laughter means that a person laughs when they do not want to, in a setting in which laughter would not usually be appropriate.Missing: solemn offense<|separator|>
[106]
Gelotophobia, No Laughing Matter - CBS News
Jul 9, 2008 · The incidence in the U.S. is about 14 percent, slightly below that of Britain. Ruch declined to say which country topped the list globally ...
[107]
Gelotophobia in Israel: on the assessment of the fear of ... - PubMed
Gelotophobia is defined as the fear of being laughed at. Empirical studies revealed that it is a valid and useful concept which deserves further attention.
[108]
The association between trait anxiety and the fear of being laughed ...
Sep 30, 2022 · We evaluated the association of GELOPH < 15 > scores with both self‐reported experiences of bullying victimization and trait anxiety measures.
[109]
The impact of laughter yoga as a NIC on health parameters in ...
Oct 29, 2024 · Laughter yoga was designed by an Indian doctor named Madan Kataria in 1995 [7]. Laughter yoga is a laughter exercise that combines yoga and ...
[110]
Laughter Yoga International: Promoting Health, Happiness, and Peace Through Laughter
### Summary of Laughter Yoga Protocols by Dr. Madan Kataria (1995)
[111]
[PDF] Your Laughter Yoga Guide
But before you begin to laugh, I want to share with you a breakthrough technology called Laughter Yoga, which. I discovered in 1995. It started as a social.Missing: protocols | Show results with:protocols
[112]
8 Best Laughter Yoga Therapy Exercises for Your Classes
Feb 22, 2022 · Laughter yoga involves gentle stretching, chanting, clapping, eye contact, and body movements. Breathing exercises prepare the lungs for a good bout of ...Missing: format 20-30
[113]
Clowning in Health Care Settings: The Point of View of Adults - NIH
Aug 19, 2016 · We used the following terms: “clown” OR “clown doctor” OR “clown therapy” OR “medical clowning” OR “hospital clown” OR “clinic clown.” The ...Missing: games | Show results with:games
[114]
Identification of Medical Clowns' Communication Skills and ...
Nov 17, 2022 · The various medical clowning skills were identified through the video-recorded simulations. The interviews then shed light on the MCs' ...
[115]
“I made you a small room in my heart”: how therapeutic clowns meet ...
Jul 27, 2023 · Although the specifics of therapeutic clowning vary according to local context, clown practices typically use embodied and artistic techniques ...
[116]
Hospital Clowning as Play Stimulus in Healthcare - PMC
Oct 30, 2014 · As a best practice, regular clowndoctor visits (“clown rounds”) to pediatric hospital wards last between 3 to 5 h and are carried out by two ...<|separator|>
[117]
Tips to Get the Most Out of Your Zoom Laughter Yoga Session
Jan 19, 2021 · We meet online for 20 minutes twice weekly. In the Laughter Yoga sessions, I guide you through a gentle warm-up, a series of laughter and deep ...
[118]
Embodied Laugh Track: Supporting VR Comedy Viewing ...
Apr 25, 2025 · Virtual reality (VR) comedy viewing with virtual audiences offers promising opportunities for social entertainment experiences.Missing: post- evidence-
[119]
Self-Management Mobile Virtual Reality Program for Women with ...
Feb 5, 2021 · We are grateful to experts in the areas of exercise, diet, laughter therapy, newborn first aid, and virtual reality, who helped develop the self ...2. Methods · 2.2. Mobile Vr Program... · 3. Results
[120]
cluster randomised trial of humour therapy in nursing homes
Humour therapy should be considered as a psychosocial intervention to reduce agitation, before starting medication. Strengths and limitations of this study.Missing: comedy | Show results with:comedy
[121]
The effects of humor therapy on nursing home residents ... - PubMed
Conclusion: We confirmed that humor therapy decreases agitation and also showed that it increases happiness. Researchers may consider evaluating impacts of ...
[122]
A structured laughter yoga therapy program on patients with ... - NIH
This study explores the potential effectiveness of laughter yoga, a combination of exercise and voluntary laughter, in alleviating chemotherapy-induced nausea ...Missing: migraine vascular
[123]
Effects of laughter yoga on health-related quality of life in cancer ...
Jun 12, 2023 · Laughter yoga in the present study had similarly alleviated pain among cancer patients undergoing chemotherapy. Researches have also ...O Outcomes · O Sample Size And... · Discussion
[124]
The effect of laughter yoga on perceived stress, burnout, and life ...
Jul 5, 2022 · A randomized controlled study was conducted on the effects of laughter yoga in reducing the perceived stress and burnout levels in nurses ...Missing: 2020s productivity
[125]
“Beyond laughter”: a systematic review to understand how ... - Frontiers
The current review found that comedy/humour interventions are beneficial for mental health recovery and wellbeing.
[126]
http://classics.mit.edu/Herodotus/history.3.iii.html
[127]
Plato on Laughter and Moral Harm - Oxford Academic
This chapter examines exactly Plato's views on the moral harmfulness of laughter, as expressed in his three distinct analyses.Missing: ambivalence | Show results with:ambivalence
[128]
https://www.biblegateway.com/passage/?search=Ecclesiastes+3%3A4&version=NIV
[129]
The History of Herodotus - The Internet Classics Archive
But it shall cost you dear that you have made me your laughing-stock." When he had so spoken, he ordered those whose business it was to scourge the priests, and ...
[130]
https://open.ocolearnok.org/whatsfunny/chapter/thomas-hobbes-human-nature/
[131]
https://pluto.huji.ac.il/~msheyd/files/Hobbes_laughter.pdf
[132]
https://www.gutenberg.org/files/4352/4352-h/4352-h.htm
[133]
Human Nature (1650) – What is Funny? - OPEN OCO
I may therefore conclude, that the passion of laughter is nothing else but sudden glory arising from some sudden conception of some eminency in ourselves, by ...
[134]
[PDF] The Place of Laughter in Hobbes's Theory of Emotions Author(s)
It is important to note that Hobbes's superiority theory of laughter com- pletely dissociates laughter from its most apparent source, the comic ("wit" and ...
[135]
An Essay on the Meaning of the Comic, by Henri Bergson
Jul 26, 2009 · Laughter is, above all, a corrective. Being intended to humiliate, it must make a painful impression on the person against whom it is directed.
[136]
[PDF] Abstract Bergson's concept of 'mechanical inelasticity' from his ...
Abstract. Bergson's concept of 'mechanical inelasticity' from his influential essay Laughter (1900,. 2010, p. 5) remains a staple of comic theory.
[137]
For Henri Bergson, laughter is what keeps us elastic and free - Aeon
Jul 7, 2020 · For philosopher Henri Bergson, laughter solves a serious human conundrum: how to keep our minds and social lives elastic.
[138]
[PDF] laughter in nietzsche's thought: a philosophical tragicomedy
Laughter is an important image in Nietzsche's writings; it is even expressed as the consummate goal to which he is calling his readers.
[139]
Nietzschean Laughter - jstor
Tragic art and Greek culture could escape decadence, Nietzsche argues, only so long as "Dionysiac poetry" and Apollonian dream could become, and remain, ...
[140]
[PDF] Nietzsche and Comedy: Provocative Laughter Amidst a Tragic ...
This is the laughter of the Dionysian reveler Silenus. As we saw above in ... Nietzsche's assertion above, recast in terms of the Apollonian and Dionysian.
[141]
[PDF] Psychology of humor Willibald Ruch
Jun 18, 2008 · A review of studies reveals that in experiments smiling occurs roughly five times more often than laugh- ter (Ruch 1990). However, “smiling” is ...
[142]
[PDF] Ruch, W. & Köhler, G. (1998). A temperament approach to humor. In
The need for a state-trait model of cheerfulness, seriousness, and bad mood arose from the experimental study of the emotional responses to humor (Ruch 1990).
[143]
The Effect of Laughter Yoga on the Psychological Resilience and ...
This study aims to reveal the effect of laughter yoga on the psychological resilience and sleep quality of nurses during the COVID-19 pandemic.Missing: positive 2020s<|separator|>
[144]
Nursing interventions to reduce mental health problems in nursing ...
Jul 1, 2025 · Each laughter therapy session includes clapping, warm-ups, breathing exercises, games, and laughter exercises. Significantly improved self- ...
[145]
[PDF] Feminist Philosophy of Humor (Author Preprint) - PhilArchive
Some key approaches to humor studies rely on idealized models of scripts and their linguistic incongruities, bracketing out politicized, gendered, embodied, and ...
[146]
https://aclanthology.org/2025.chum-1.8.pdf
[147]
Affect Theory in the Throat of Laughter | Feminist Media Histories
Apr 1, 2021 · This article pursues laughter as an affect that bridges the gap between feminist comedy studies and feminist affect theory.
[148]
[PDF] Can AI Make Us Laugh? Comparing Jokes Generated by Witscript ...
Jan 19, 2025 · Some AI-written jokes ranked higher than some of the human-written jokes, and the funniest joke, as measured by quantity of laughter, was ...Missing: 2020s | Show results with:2020s
[149]
Can Artificial Intelligence Learn the Nuances of Human Humor?
Jul 28, 2025 · Toplyn is among a number of researchers who believe that a more humorous A.I. could produce real-world benefits. As the loneliness epidemic ...Missing: 2020s | Show results with:2020s