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Lateral sulcus

The lateral sulcus, also known as the Sylvian fissure, is a deep and prominent groove on the lateral surface of each cerebral hemisphere that separates the frontal and parietal lobes superiorly from the temporal lobe inferiorly, while also bounding the insula deep within its cavity.^[1] This structure is the most consistent and distinct landmark on the lateral hemispheric surface of the brain, formed by the apposition of the frontoparietal and temporal opercula over the insula.^[1] It extends anteroposteriorly from near the basal forebrain, beginning at the anterior clinoid process and stem of the middle cerebral artery, to the lateral surface where it branches into three main rami.^[2] Anatomically, the lateral sulcus is divided into a superficial portion—comprising the stem and the anterior horizontal, anterior ascending, and posterior rami—and a deep portion known as the Sylvian cistern, which includes sphenoidal and operculoinsular compartments containing segments of the middle cerebral artery (M1-M3).^[1] The anterior horizontal ramus extends forward to separate the orbital and triangular parts of the inferior frontal gyrus, the ascending ramus rises to demarcate the triangular and opercular parts of the same gyrus, and the posterior ramus, the longest branch, runs backward to separate the parietal and temporal lobes before ending in the groove of the supramarginal gyrus.^[3] Deep to the sulcus lies the insular lobe, a hidden cortical region involved in various functions.^[3] Developmentally, the lateral sulcus emerges as an early feature during embryogenesis, becoming visible around 12-14 weeks of gestation through differential migration of neural cells from the frontal, parietal, temporal lobes, and insula, and achieving its full grooved form by approximately 19 weeks.^[1] Functionally, it demarcates regions critical for higher cognitive processes: the surrounding frontal and temporal cortices house language areas such as Broca's and Wernicke's areas, auditory processing in Heschl's gyrus, and visceral sensory integration within the insula.^[1] Clinically, the lateral sulcus holds significant relevance in neurology and neurosurgery; it is a common site for middle cerebral artery aneurysms, arachnoid cysts, and ischemic strokes, where imaging may reveal signs like the hyperdense middle cerebral artery on CT.^[1] In surgical contexts, it serves as a vital corridor for transsylvian approaches to access deep structures, such as for aneurysm clipping or tumor resection, often employing an "inside-out" technique to navigate its compartments safely.^[1] Radiographically, it appears as a clear cleft on MRI and CT, aiding in the assessment of adjacent pathologies and vascular relations.^[2]

Anatomy

Location and boundaries

The lateral sulcus, also known as the Sylvian fissure, is a deep horizontal fissure situated on the lateral surface of each cerebral hemisphere, demarcating the boundary between the frontal and parietal lobes superiorly and the temporal lobe inferiorly. It originates at the anterior perforated substance on the basal surface of the brain, immediately adjacent to the lateral olfactory stria, and extends posteriorly in an anteroposterior direction along the superolateral aspect of the hemisphere, terminating in the inferior parietal lobule near the supramarginal gyrus.^[4]^[5]^[1] The sulcus exhibits an average depth of approximately 1-2 cm, facilitating the accommodation of its principal extensions, including the anterior ramus, which projects forward to delineate subdivisions of the inferior frontal gyrus, and the posterior ramus, the longest branch that courses backward and slightly superiorly for about 8 cm before terminating near the supramarginal gyrus. The superior bank of the sulcus is formed by the frontal and parietal opercula, which are the lid-like extensions of the frontal and parietal lobes that overhang the sulcal depth. In contrast, the inferior bank comprises the superior temporal gyrus, providing a stable inferior margin along the temporal lobe's upper edge.^[6]^[5]^[7] Deep within the lateral sulcus lies the insula, a buried cortical region whose lateral surface is concealed by the approximation of the frontal, parietal, and temporal opercula, effectively closing over the sulcus in the mature brain and forming the lateral opercular wall. This configuration underscores the sulcus's role in encapsulating insular structures while maintaining clear lobar separations on the external cerebral surface.^[5]^[4]

Branches and relations

The lateral sulcus, also known as the Sylvian fissure, typically divides into three principal branches on the superolateral surface of the cerebral hemisphere: the anterior horizontal ramus, the anterior ascending ramus, and the posterior ramus.^[4] The anterior horizontal ramus is a short, horizontal extension that courses into the inferior frontal gyrus, separating the pars orbitalis from the pars triangularis.^[1] The anterior ascending ramus, also referred to as the vertical ramus, projects upward from the horizontal ramus into the inferior frontal gyrus, delineating the boundary between the pars triangularis and the pars opercularis.^[1] These anterior branches collectively contribute to the subdivision of the inferior frontal gyrus and are integral to the region's gyral architecture.^[4] The posterior ramus represents the longest branch of the lateral sulcus, extending horizontally and posteriorly along the superior margin of the superior temporal gyrus for an average length of approximately 75 mm, before ascending slightly to reach the temporoparietal junction.^[1] This ramus separates the temporal operculum inferiorly from the frontoparietal operculum superiorly and terminates in the inferior parietal lobule, in close proximity to the supramarginal gyrus and angular gyrus.^[1] Anteriorly, the stem of the lateral sulcus arises lateral to the anterior perforated substance and lies adjacent to the deeper extensions of the ambient cistern, including the transverse fissure of Bichat, which forms part of the boundary between the thalamus and parahippocampal structures.^[8] The middle cerebral artery traverses the length of the sulcus, with its main trunk and branches (including M1 sphenoidal, M2 insular, and M3 opercular segments) running within the fissure's deeper compartments, supplying adjacent cortical regions.^[9] The lateral sulcus is overlain by opercula from the surrounding lobes, a process known as opercularization, which conceals the underlying insula. The frontal operculum comprises the pars orbitalis, triangularis, and opercularis of the inferior frontal gyrus, forming the anterior covering.^[1] The temporal operculum consists primarily of the superior temporal gyrus, underlying the posterior ramus.^[1] Posteriorly, the parietal operculum includes the lower portion of the postcentral gyrus and the supramarginal gyrus, completing the superior margin over the sulcus.^[1] This opercular arrangement integrates the sulcus into the broader lateral convexity of the hemisphere, facilitating its role as a major anatomical divider.^[4]

Development and variation

Embryonic origins

The lateral sulcus, also known as the Sylvian fissure, begins to form during the early second trimester of gestation, becoming identifiable as a shallow depression on the lateral surface of the brain around 12 to 14 weeks. This initial structure arises from the invagination of the insular cortex, which emerges as a distinct conical region surrounded by the circular sulcus by approximately 18 weeks, creating the foundational fissure that separates the emerging temporal lobe from the frontal and parietal lobes.^[1]^[10] By 19 weeks, the fissure deepens into a groove, establishing the Sylvian fossa with the insula as its floor.^[1] The deepening of the lateral sulcus is driven by the expansion of the telencephalic vesicles, where differential growth rates occur between the temporal lobe and the adjacent frontal and parietal regions. Insular neurons migrate obliquely from the pallial/subpallial boundary around the basal ganglia, contrasting with the radial migration patterns in other cortical areas, which results in slower insular expansion relative to the overlying opercula. This heterogeneous growth— with opercular regions expanding at about 110% weekly compared to 90% for the insula—progresses notably from 19 to 24 weeks, widening and elongating the sulcus while accommodating the increasing cortical surface area.^[11]^[10] Opercular development further refines the sulcus by progressively covering the insula, beginning with the frontal operculum around 20 weeks of gestation, which grows dorsally to override the upper insula. The temporal operculum follows, covering the ventral insula by 23 weeks, while the parietal operculum develops later, contributing to the posterior coverage; these processes approximate complete enclosure by 28 to 29 weeks, though full maturation continues until birth. Major closure of the opercula over the insula occurs between 23 and 25 weeks, transforming the shallow fissure into its characteristic deep, C-shaped structure.^[12]^[1]^[10] Genetic factors play a key role in regulating the timing and coordination of opercular closure, with differential gene expression patterns distinguishing the insula from the opercula as early as 23 weeks; notable genes include SH3YL1 and SOCS7 in the subpial granular zone, and NTF3, IRX2, and DOCK7 in cortical layers, influencing neuronal migration and regional growth rates. The FOXP2 gene, involved in broader neural development and expressed in perisylvian regions critical for language, contributes to the maturation of frontal and temporal opercular areas, potentially affecting closure dynamics through its regulation of transcription networks in these domains.^[10]^[13] Evolutionarily, the lateral sulcus represents a conserved feature across primates, present in nonhuman species such as chimpanzees, where it delineates similar lobar boundaries but exhibits less asymmetry and depth. In humans, the sulcus deepens significantly due to accelerated cortical expansion and enhanced gyrification, accommodating the enlarged association cortices in the frontal, parietal, and temporal lobes, a adaptation linked to advanced cognitive functions.^[14]^[15]

Anatomical variations

The lateral sulcus, also known as the Sylvian fissure, displays notable anatomical variations in its morphology and branching patterns across human populations, influencing cortical organization without compromising function in healthy individuals. One variation involves incomplete opercularization, where the opercula fail to fully cover the insula, resulting in partial exposure of the insular surface. This is a rare finding often associated with developmental disorders. Asymmetries in sulcus length and depth represent another frequent variation, with the left lateral sulcus typically longer and extending more posteriorly than the right in 65-70% of cases. The right sulcus tends to be shallower and more curved superiorly, contributing to a steeper ascent at its posterior termination. These asymmetries are observed in 60-70% of right-handed individuals and show correlations with handedness, particularly in males, where consistent right-handers exhibit bilaterally longer horizontal segments compared to mixed-handers or left-handers.^[16]^[17] Accessory sulci and additional short rami arising from the main stem of the lateral sulcus occur in 10-15% of cases, often manifesting as minor branches such as the triangular or diagonal sulci within the frontoparietal operculum. These supplementary structures can subtly alter the boundaries of the temporal and frontal opercula, potentially expanding the adjacent temporal lobe margins by a few millimeters. Prevalence varies, with the triangular sulcus present in about 51% of hemispheres overall, though shorter accessory rami are less common and typically unilateral.^[18]^[19] Population-level prevalence of these variations differs across ethnic groups, with MRI studies indicating higher rates of asymmetry in East Asian cohorts compared to Caucasians. For instance, Chinese individuals demonstrate greater leftward dominance in sulcal length and depth in the temporal and insular regions, with asymmetry indices up to 20% higher than in Caucasian groups. In contrast, some Asian subgroups show relatively more symmetric configurations in 20-30% of cases, potentially linked to genetic factors influencing cortical folding.^[20]^[21] Despite these structural differences, anatomical variations in the lateral sulcus generally do not lead to functional deficits in healthy individuals, owing to the brain's neuroplasticity, which enables compensatory adjustments in cortical connectivity and folding patterns during development. Functional imaging reveals that inter-subject variability in sulcal morphology correlates with subtle shifts in activation during language and sensory tasks, but overall network efficiency remains preserved through adaptive reorganization of adjacent gyri.^[22]^[23]

Functions

Structural role in lobe separation

The lateral sulcus, also known as the Sylvian fissure, functions primarily as a deep anatomical landmark that delineates the boundaries between the temporal lobe inferiorly and the frontal and parietal lobes superiorly, thereby organizing the superolateral surface of the cerebral hemisphere into distinct lobar regions.^[24] This separation is essential for the basic compartmentalization of cortical areas, with the sulcus extending laterally from the basal forebrain to divide the expansive temporal lobe from the overlying frontal operculum and parietal operculum.^[25] By creating this vertical demarcation, the sulcus facilitates the spatial arrangement of gyri and sulci within each lobe, contributing to the overall architecture that supports modular brain functions.^[26] In terms of hemispheric asymmetry, the lateral sulcus exhibits notable differences between the left and right hemispheres, particularly in right-handed individuals, where the left sulcus is typically longer and more horizontally oriented, enhancing the exposure of perisylvian language areas and supporting left-hemisphere dominance for linguistic processing.^[27] This asymmetry, observed in structural MRI studies, correlates with the facilitation of language lateralization, as the extended leftward configuration allows for greater development of adjacent cortical regions involved in speech comprehension and production.^[28] Such variations underscore the sulcus's role in establishing functional hemispheric specialization from a structural base. The insula, folded inward and covered by the opercula of the frontal, parietal, and temporal lobes, lies deep to the sulcus.^[4] Furthermore, the presence and configuration of the lateral sulcus significantly influence adjacent gyral patterns, bounding the superior temporal gyrus along its inferior margin and the inferior frontal gyrus along its superior margin, thereby shaping the folding of these critical language- and auditory-related structures. This demarcation guides the parallel orientation of the superior temporal gyrus to the sulcus, promoting efficient packing of auditory association cortex.^[4] Comparatively, the lateral sulcus in humans is wider and more pronounced than in other mammals, reflecting the evolutionary expansion of association cortices in the temporal and frontal lobes to accommodate advanced cognitive capacities such as language and social cognition.^[29] In non-human primates and other mammals, the sulcus is shallower and less extensive, limiting the volume available for higher-order processing areas hidden within or adjacent to it.^[14] This human-specific widening enables greater cortical surface area for complex neural computations.^[29]

Involvement in cortical networks

The lateral sulcus plays a pivotal role in language networks by delineating key cortical regions involved in speech comprehension and production. Its posterior ramus forms the inferior boundary of the superior temporal gyrus, which encompasses Wernicke's area responsible for language comprehension.^[30] Similarly, the anterior portion of the lateral sulcus bounds the inferior frontal gyrus superiorly, where Broca's area resides and supports speech articulation. These boundaries facilitate the integration of phonological and semantic processing across the perisylvian region. In sensory integration, the superior bank of the lateral sulcus, particularly within the temporal operculum, hosts Heschl's gyrus, the site of the primary auditory cortex that initiates sound processing.^[31] This structure receives thalamic inputs and relays auditory information to higher association areas along the sulcal banks, enabling the decoding of complex acoustic signals such as speech.^[32] Connectivity along the lateral sulcus is bolstered by branches of the middle cerebral artery, which course through the sulcus to perfuse the surrounding cortex and white matter tracts, including those supporting the arcuate fasciculus.^[33] The arcuate fasciculus, arching superiorly around the sulcus endpoint, interconnects frontal, temporal, and parietal language hubs, facilitating rapid information transfer for verbal tasks.^[34] Beneath the sulcus, the insula integrates with the salience network, linking auditory and linguistic inputs to emotional and attentional processing for contextual awareness.^[35] Functional magnetic resonance imaging (fMRI) studies reveal robust activations adjacent to the lateral sulcus during speech production and comprehension tasks, with heightened signals in the superior temporal gyrus for semantic parsing and in perisylvian regions for articulatory planning.^[36] These patterns underscore the sulcus's role in coordinating dynamic neural ensembles for real-time language exchange.^[37]

Clinical significance

Associated neurological conditions

Damage to the arcuate fasciculus, a white matter tract that arches around the posterior end of the lateral sulcus (also known as the Sylvian fissure), near its posterior ramus, is a primary cause of conduction aphasia, characterized by impaired repetition of speech despite relatively preserved comprehension and fluency.^[9]^[38] Extensive lesions encompassing the perisylvian region surrounding the lateral sulcus, often in the territory of the left middle cerebral artery, result in global aphasia, involving severe impairments across all language modalities including comprehension, production, reading, and writing.^[39]^[40] Strokes affecting the middle cerebral artery branches that supply the insula—located deep within the lateral sulcus—frequently lead to neurological deficits due to insular involvement, with such infarcts occurring in a significant proportion of middle cerebral artery stroke cases.^[41] Right insular lesions are associated with spatial neglect, a condition where patients fail to attend to stimuli on the left side of space, contributing to functional impairments in daily activities.^[42] Additionally, insular strokes can disrupt autonomic regulation, resulting in cardiac arrhythmias, ventricular dysfunction, or stress responses such as ulcers, particularly following right-sided ischemia.^[43]^[44] Temporal lobe epilepsy often involves seizure origins near the banks of the lateral sulcus, including the superior temporal gyrus and adjacent opercular regions, with perisylvian propagation patterns observed in some cases in surgical cohorts.^[45]^[46] These seizures may manifest with complex auras, motor symptoms, or autonomic features due to the involvement of cortical areas bordering the sulcus.^[46] Schizencephaly, a developmental malformation characterized by clefts lined with gray matter that frequently involve the region of the Sylvian fissure (lateral sulcus), is associated with cognitive delays ranging from mild developmental impairment to severe intellectual disability, depending on the extent and bilaterality of the lesions.^[47]

Diagnostic and surgical relevance

The lateral sulcus, also known as the Sylvian fissure, is prominently visible on magnetic resonance imaging (MRI) and computed tomography (CT) scans due to its deep, fluid-filled structure, making it a reliable anatomical landmark for delineating the boundaries between the frontal, parietal, and temporal lobes in neuroimaging protocols.^[48] This visibility facilitates precise lobe identification during routine diagnostic evaluations and preoperative assessments.^[49] In volumetric analysis, measurements of the sulcus width and depth on MRI are utilized to quantify cortical atrophy, particularly in neurodegenerative conditions, where sulcal widening correlates with neuronal loss and tissue volume reduction.^[50] In neurosurgical procedures, the Sylvian fissure split technique involves meticulous dissection of the fissure to provide access to underlying structures, enabling safe exposure of the insula during aneurysm clipping of the middle cerebral artery or resection of insular tumors while preserving adjacent vascular and neural elements.^[51] This approach minimizes retraction injury by following the natural arachnoidal planes, allowing surgeons to navigate the proximal fissure for basal subarachnoid exposure without excessive manipulation of the frontal or temporal opercula.^[52] For middle cerebral artery aneurysms, intraoperative navigation systems leverage the sulcus branches as guiding landmarks to optimize exposure.^[53] Endoscopic techniques employing trans-sulcal trajectories utilize the fissure's corridor to reach deep-seated lesions, such as periventricular tumors or hemorrhages, by advancing instruments along the sulcal path to limit cortical transgression and associated damage.^[54] This minimally invasive method engages subcortical U-fibers sparingly, reducing the risk of postoperative deficits like seizures or motor impairments, and is particularly advantageous for eloquent brain regions where open approaches might cause greater disruption.^[55] Advances in diffusion tensor imaging (DTI) enable preoperative tracking of white matter fibers coursing along or adjacent to the lateral sulcus, such as the arcuate fasciculus, to inform trajectory planning and avoid disruption during surgery.^[56] By integrating DTI-derived fiber maps with neuronavigation, surgeons can visualize fiber orientation relative to the sulcus, enhancing the precision of resections near the insula or temporal lobe and improving functional outcomes.^[57]

History and nomenclature

Discovery and early descriptions

The first specific depiction of the lateral sulcus appeared in 1600 in the Tabulae Pictae by Girolamo Fabrici d'Acquapendente.^[1] A graphic representation and description followed in 1641 by Thomas Bartholin in Casp. Bartolini Institutiones Anatomicae, crediting his teacher Franciscus Sylvius.^[1] Sylvius provided a detailed description in his 1663 work Disputationem Medicarum, emphasizing the sulcus's role in demarcating the temporal lobe from the frontal and parietal lobes, marking a shift toward systematic neuroanatomical mapping.^[1] Building on this, Thomas Willis contributed significantly in 1664 with his Cerebri Anatome, featuring detailed illustrations—crafted with input from Christopher Wren—that highlighted the sulcus's considerable depth and its separation of cerebral lobes, advancing the understanding of brain topography through comparative dissections of human and animal specimens.^[58] By the 19th century, advancements linked the lateral sulcus to functional anatomy, particularly through Paul Broca's 1861 studies on patients with aphasia, where he localized speech production to the posterior inferior frontal gyrus adjacent to the sulcus, based on postmortem examinations that revealed lesions in this region.^[59] Broca's findings, presented at the Société d'Anthropologie de Paris, established an early connection between the sulcus's position and language-related cortical areas, influencing subsequent localization theories.^[60] Concurrently, early microscopic investigations were limited by technological constraints, but Camillo Golgi's refinements in the 1880s to his silver chromate staining technique—initially developed in 1873—enabled better visualization of neuronal architecture within and around sulcal regions, facilitating histological studies of cortical folding.^[61]

Naming conventions and eponyms

The eponym "Sylvian fissure" originated from the description provided by Franciscus Sylvius in his 1663 anatomical work Disputationem Medicarum, where he detailed the prominent cleft separating the cerebral hemispheres' lobes, leading to its naming in his honor despite earlier depictions by others.^[62] This term gained widespread adoption in anatomical literature during the 19th century, appearing frequently in texts by scholars such as Friedrich Arnold, who referenced it as a key landmark in cerebral topography by 1851.^[63] In the 20th century, there was a shift toward descriptive nomenclature to promote universality and avoid personal attributions, with "lateral sulcus" emerging as the preferred term in modern anatomical references. The Federative Committee on Anatomical Terminology's Terminologia Anatomica (1998) explicitly favored non-eponymous designations like sulcus lateralis cerebri for this structure, reflecting a broader policy discouraging eponyms such as "Sylvian fissure" in official usage.^[64] Alternative names persist in some contexts, including the misnomer "fissure of Rolando," which actually refers to the central sulcus separating the frontal and parietal lobes.^[65] Internationally, Latin forms like fissura Sylvii remain in use within classical and some contemporary texts, particularly in European anatomical traditions.^[66] Debates on eponym retention continue in neuroscience literature, with arguments for preserving historical names like "Sylvian fissure" for their familiarity in clinical and research settings, contrasted against calls for standardization to enhance global communication, as noted in reviews from the early 2000s onward.^[67] Standardization efforts by the International Federation of Associations of Anatomists (IFAA) further solidified this evolution; the Nomina Anatomica (6th edition, 1983) introduced fissura cerebri lateralis as the official term, a preference reaffirmed and refined in the Terminologia Anatomica updates of 1998 and 2019 under the Federative International Programme for Anatomical Terminology (FIPAT), emphasizing descriptive precision over eponyms.^[68]

Cultural and representational aspects

Depictions in art and media

The lateral sulcus, also known as the Sylvian fissure, has been a prominent feature in artistic and scientific depictions of the brain since the Renaissance, serving as a key landmark for illustrating cerebral lobe separation and cortical folding. Leonardo da Vinci's detailed anatomical sketches from around 1510, including those of the brain's external surface and sectional views, contributed to early neuroanatomical observations by blending artistic precision with studies of brain structures. These pen-and-ink drawings, preserved in collections such as the Royal Library at Windsor Castle, emphasized the brain's convoluted surface to explore human physiology beyond mere aesthetics.^[69] In the 19th century, advancements in histological techniques enabled more intricate engravings of brain architecture, particularly through Camillo Golgi's pioneering silver staining method introduced in 1885. Golgi's illustrations, derived from his "black reaction" technique, highlighted neuronal arborizations and dendritic patterns, revealing the intricate cytoarchitecture of the nervous system. These engravings, featured in Golgi's seminal works on the central nervous system, transformed artistic representations by providing microscopic fidelity that influenced subsequent neuroscientific visualizations.^[70] Contemporary depictions leverage digital technologies for enhanced clarity and interactivity in educational contexts. The 6th edition of Netter's Atlas of Human Anatomy (2014) incorporates 3D reconstructions and layered illustrations that prominently feature the lateral sulcus, delineating its role in dividing the frontal and parietal lobes from the temporal lobe to facilitate clinical and pedagogical comprehension. Similarly, MRI-based renderings in scientific literature, such as a 1997 study in Schizophrenia Bulletin analyzing anomalous lateral sulcus asymmetry via high-resolution imaging, produce volumetric models that quantify and visualize hemispheric differences in sulcal depth and orientation.^[71] These digital renderings underscore the sulcus's variability, aiding research into functional lateralization. The integration of the lateral sulcus into virtual reality (VR) models has further revolutionized its portrayal in medical education since the 2010s, allowing users to navigate immersive 3D brain simulations. Early VR applications position the lateral sulcus as a central interactive element in neuroanatomy resources, enabling learners to explore its contours, adjacent gyri, and clinical relevance in a dynamic environment that surpasses traditional 2D illustrations.^[72] This approach has been validated in studies showing improved spatial understanding and retention among medical students, with the sulcus often highlighted to demonstrate its boundaries in virtual dissections. Recent advancements as of 2024 include augmented reality (AR) models for neuroanatomy education that incorporate the lateral sulcus in interactive quizzes and simulations.^[72]

References in popular culture

The lateral sulcus, also known as the Sylvian fissure, appears in popular literature exploring neurological disorders, particularly through discussions of aphasia and related conditions. In Oliver Sacks' 1985 book The Man Who Mistook His Wife for a Hat, the author describes cases of patients with aphasia resulting from lesions in perisylvian regions, highlighting how damage near the lateral sulcus impairs language comprehension and production. Similarly, V.S. Ramachandran's 1998 book Phantoms in the Brain popularizes the structure in the context of phantom limb phenomena, noting its role in separating the temporal lobe from the parietal and frontal lobes, where sensory remapping occurs after amputation. In film and television, the lateral sulcus is alluded to in narratives centered on brain recovery and diagnostics. The medical drama series House M.D. (2004–2012) mentions the structure across multiple episodes during differential diagnoses of temporal lobe disorders, such as seizures or aphasia, underscoring its relevance to clinical puzzles. Educational media often simplifies the lateral sulcus for broader audiences, portraying it metaphorically as a "brain's highway divider" that separates key lobes for sensory and language processing. For instance, the 2015 YouTube episode "Central Nervous System: Crash Course Anatomy & Physiology #11" from the Crash Course series explains its role in dividing the temporal lobe, making complex neuroanatomy accessible.^[73] Popular depictions sometimes foster misconceptions by conflating the lateral sulcus with the central sulcus, leading to public misunderstandings about its distinction from motor-related functions versus language and auditory pathways.

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Results indicate that in humans there is a processing stream from AI on mesial HG to an associational auditory field (PLST) on the lateral surface of the ...
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Neuroanatomy, Middle Cerebral Artery - StatPearls - NCBI Bookshelf
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Arcuate Fasciculus - an overview | ScienceDirect Topics
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The Salience Network: A Neural System for Perceiving and ...
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Task-dependent modulation of regions in the left temporal cortex ...
Jan 1, 2015 · Our results not only confirm the critical role of the left lateral temporal cortex in auditory sentence comprehension but further demonstrate that task demands ...
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Our results argue that a shared neural mechanism supporting both production and comprehension facilitates communication.
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Dissociating the white matter tracts connecting the temporo-parietal ...
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Aphasia - StatPearls - NCBI Bookshelf - NIH
Oct 29, 2024 · Global Aphasia. Global aphasia results from lesions that vary in size and location, primarily affecting the brain areas in the peri-Sylvian ...Missing: extensive sulcus
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Global aphasia without hemiparesis: A case series - PMC - NIH
[1] Global aphasia occurs after large perisylvian lesions in the territory of left middle cerebral artery (MCA) and is associated with hemiparesis on the ...
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Middle Cerebral Artery Stroke - StatPearls - NCBI Bookshelf - NIH
The middle cerebral artery (MCA) is the most common artery involved in acute stroke. It branches directly from the internal carotid artery and consists of four ...
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Awareness of the Functioning of One's Own Limbs Mediated by the ...
Here, we use lesion mapping in 27 stroke patients to show that the right posterior insula is commonly damaged in patients with anosognosia for hemiplegia/ ...
[45]
Acute right insular ischaemic lesions and poststroke left ventricular ...
Jan 18, 2023 · Our results support preliminary evidence that acute ischaemic stroke in distinct brain regions of the central autonomic network may directly impair cardiac ...
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Ischemic insular damage and stress ulcer in patients of acute ...
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The Insula and Its Epilepsies - PMC - PubMed Central - NIH
Long-term seizure freedom rates are 66% in temporal lobe epilepsy, 46% in occipital and parietal lobe epilepsy, and 27% in frontal lobe epilepsy.
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Schizencephaly - StatPearls - NCBI Bookshelf - NIH
It most commonly presents as developmental delay, seizures, and weakness. This activity reviews the etiology, pathophysiology, evaluation, and treatment of ...
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[52]
Neuroimaging in posterior cortical atrophy: an integrative review for ...
On MRI, key anatomical landmarks for analysis include: Medial surface: parieto-occipital sulcus, calcarine sulcus; cuneus and lingual gyri.
[53]
Cortical and Subcortical Brain Atrophy Assessment Using Simple ...
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Transsylvian-Transinsular Approaches to the Insula and Basal Ganglia
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Sylvian fissure splitting revisited: Applied arachnoidal anatomy and ...
We introduce a live rat aortoiliac model to practice the basic skills of Sylvian fissure splitting based on its arachnoidal microanatomy.
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Intraoperative visualization of cerebral aneurysms using navigated ...
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[57]
Minimally invasive surgery and transsulcal parafascicular approach ...
Sep 26, 2019 · A trans-sulcal route minimises transgressed cortex, engages subcortical U-fibres, and can be applied to eloquent cortical and white matter ...
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Utilizing tubular retractors in colloid cyst resection - PubMed Central
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Fiber Tractography Based on Diffusion Tensor Imaging Compared ...
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surgical outcomes and predictive value of diffusion tensor imaging ...
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Thomas Willis and the background to Cerebri Anatome - PMC - NIH
In 1664 Thomas Willis (1621-1675) published a text on the brain and nerves that was to be deeply influential for the next two centuries. Initially, Cerebri ...Missing: lateral sulcus
[63]
high resolution MR imaging of the brains of Leborgne and Lelong
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Classics in the History of Psychology -- Broca (1861b English)
The faculty of articulated language is likely located in the anterior lobes, specifically the frontal lobe, possibly the third frontal convolution.
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A constant sulcus was not recognized until the mid-1600s; it was named "the fissure of Sylvius," after the person who had always been considered as the one who ...
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Historical Remarks (Chapter 1) - Applied Cranial-Cerebral Anatomy
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[68]
Toward a Common Terminology for the Gyri and Sulci of the Human ...
The triangular insula of Reil lies in the depths of the lateral sulcus and is covered by the frontal, frontoparietal, parietal, and temporal opercula (Türe et ...
[69]
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Central Nervous System | SpringerLink
Oct 29, 2020 · Fissura Sylvii (Sylvian fissure) splits the upper border of the temporal from the parietal lobes. Convolutions: High level of cerebral ...
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Eponymy in neuroscience has been used for a long time as a way to identify and recognize scientific issues, such as diseases, syndromes, methods, processes ...Missing: international variations Fissura Sylvii
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https://thejns.org/view/journals/j-neurosurg/141/3/article-p865.xml
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Leonardo da Vinci's studies of the brain - PubMed
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Leonardo da Vinci (1452-1519) - The brain - Royal Collection Trust
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[75]
The Original Histological Slides of Camillo Golgi and His ...
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[76]
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when virtual reality meets medical education - PubMed
The authors sought to construct, implement, and evaluate an interactive and stereoscopic resource for teaching neuroanatomy, accessible from personal computers.Missing: lateral sulcus 2010s
[78]
Creating a neuroanatomy education model with augmented reality ...
Apr 26, 2024 · This study evaluates augmented reality (AR)– and virtual reality (VR)–based educational models for neuroanatomy education.
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Central Nervous System: Crash Course Anatomy & Physiology #11
Mar 23, 2015 · Today Hank talks about your central nervous system. In this episode, we'll explore how your brain develops and how important location is for ...Missing: lateral sulcus highway divider