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1.
Hum Brain Mapp ; 45(9): e26771, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38925589

RESUMO

Neuroimaging studies have consistently demonstrated concurrent activation of the human precuneus and temporal pole (TP), both during resting-state conditions and various higher-order cognitive functions. However, the precise underlying structural connectivity between these brain regions remains uncertain despite significant advancements in neuroscience research. In this study, we investigated the connectivity of the precuneus and TP by employing parcellation-based fiber micro-dissections in human brains and fiber tractography techniques in a sample of 1065 human subjects and a sample of 41 rhesus macaques. Our results demonstrate the connectivity between the posterior precuneus area POS2 and the areas 35, 36, and TG of the TP via the fifth subcomponent of the cingulum (CB-V) also known as parahippocampal cingulum. This finding contributes to our understanding of the connections within the posteromedial cortices, facilitating a more comprehensive integration of anatomy and function in both normal and pathological brain processes. PRACTITIONER POINTS: Our investigation delves into the intricate architecture and connectivity patterns of subregions within the precuneus and temporal pole, filling a crucial gap in our knowledge. We revealed a direct axonal connection between the posterior precuneus (POS2) and specific areas (35, 35, and TG) of the temporal pole. The direct connections are part of the CB-V pathway and exhibit a significant association with the cingulum, SRF, forceps major, and ILF. Population-based human tractography and rhesus macaque fiber tractography showed consistent results that support micro-dissection outcomes.


Assuntos
Imagem de Tensor de Difusão , Macaca mulatta , Vias Neurais , Lobo Parietal , Lobo Temporal , Humanos , Lobo Temporal/diagnóstico por imagem , Lobo Temporal/fisiologia , Lobo Temporal/anatomia & histologia , Lobo Parietal/diagnóstico por imagem , Lobo Parietal/fisiologia , Lobo Parietal/anatomia & histologia , Animais , Imagem de Tensor de Difusão/métodos , Masculino , Adulto , Feminino , Vias Neurais/diagnóstico por imagem , Vias Neurais/anatomia & histologia , Vias Neurais/fisiologia , Adulto Jovem , Axônios/fisiologia , Conectoma , Substância Branca/diagnóstico por imagem , Substância Branca/anatomia & histologia , Substância Branca/fisiologia , Giro do Cíngulo/diagnóstico por imagem , Giro do Cíngulo/fisiologia , Giro do Cíngulo/anatomia & histologia
2.
Nature ; 629(8013): 861-868, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38750353

RESUMO

A central assumption of neuroscience is that long-term memories are represented by the same brain areas that encode sensory stimuli1. Neurons in inferotemporal (IT) cortex represent the sensory percept of visual objects using a distributed axis code2-4. Whether and how the same IT neural population represents the long-term memory of visual objects remains unclear. Here we examined how familiar faces are encoded in the IT anterior medial face patch (AM), perirhinal face patch (PR) and temporal pole face patch (TP). In AM and PR we observed that the encoding axis for familiar faces is rotated relative to that for unfamiliar faces at long latency; in TP this memory-related rotation was much weaker. Contrary to previous claims, the relative response magnitude to familiar versus unfamiliar faces was not a stable indicator of familiarity in any patch5-11. The mechanism underlying the memory-related axis change is likely intrinsic to IT cortex, because inactivation of PR did not affect axis change dynamics in AM. Overall, our results suggest that memories of familiar faces are represented in AM and perirhinal cortex by a distinct long-latency code, explaining how the same cell population can encode both the percept and memory of faces.


Assuntos
Reconhecimento Facial , Memória de Longo Prazo , Reconhecimento Psicológico , Lobo Temporal , Animais , Face , Reconhecimento Facial/fisiologia , Macaca mulatta/fisiologia , Memória de Longo Prazo/fisiologia , Neurônios/fisiologia , Córtex Perirrinal/fisiologia , Córtex Perirrinal/citologia , Estimulação Luminosa , Reconhecimento Psicológico/fisiologia , Lobo Temporal/anatomia & histologia , Lobo Temporal/citologia , Lobo Temporal/fisiologia , Rotação
3.
World Neurosurg ; 183: e540-e548, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38163584

RESUMO

BACKGROUND: For surgical interventions, a precise understanding of the anatomical variations of the brain and defined anatomical landmarks to demarcate the regions of the temporal lobe is essential. Many anatomical studies have facilitated important surgical approaches to the temporobasal region. Because there is considerable sulcal variability, morphological analysis of the brain is imperative. The aim of this study was to define the boundaries of the temporal and occipital lobes and to define the variations in sulci and gyri in the inferior aspect. METHODS: In 110 cerebral hemispheres variations were identified and the major landmarks of the gyral-sulcal pattern at the inferior aspect of the brain were defined. RESULTS: The anatomy of the inferior aspect of the brain is defined in detail by morphological analysis of formalin-fixed hemispheres with a view to informing important surgical approaches. CONCLUSIONS: Since the literature defines no clear separation between the temporal and occipital lobes, certain landmarks such as the preoccipital notch and a basal temporo-occipital line were suggested as ways of making the distinction. The parahippocampal ramus is a constant structure that can be used as a reliable landmark for the posterior end of the hippocampus.


Assuntos
Neurocirurgia , Humanos , Lobo Occipital/cirurgia , Lobo Occipital/anatomia & histologia , Lobo Temporal/cirurgia , Lobo Temporal/anatomia & histologia , Encéfalo , Cadáver
4.
Surg Radiol Anat ; 45(7): 849-858, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37195302

RESUMO

INTRODUCTION: Optic radiations are tracts of particular interest for neurosurgery, especially for temporal lobe resection, because their lesion is responsible for visual field defects. However, histological and MRI studies found a high inter-subject variability of the optic radiation anatomy, especially for their most rostral extent inside the Meyer's temporal loop. We aimed to better assess inter-subject anatomical variability of the optic radiations, in order to help to reduce the risk of postoperative visual field deficiencies. METHODS: Using an advanced analysis pipeline relying on a whole-brain probabilistic tractography and fiber clustering, we processed the diffusion MRI data of the 1065 subjects of the HCP cohort. After registration in a common space, a cross-subject clustering on the whole cohort was performed to reconstruct the reference optic radiation bundle, from which all optic radiations were segmented on an individual scale. RESULTS: We found a median distance between the rostral tip of the temporal pole and the rostral tip of the optic radiation of 29.2 mm (standard deviation: 2.1 mm) for the right side and 28.8 mm (standard deviation: 2.3 mm) for the left side. The difference between both hemispheres was statistically significant (p = 1.10-8). CONCLUSION: We demonstrated inter-individual variability of the anatomy of the optic radiations on a large-scale study, especially their rostral extension. In order to better guide neurosurgical procedures, we built a MNI-based reference atlas of the optic radiations that can be used for fast optic radiation reconstruction from any individual diffusion MRI tractography.


Assuntos
Imagem de Difusão por Ressonância Magnética , Imagem de Tensor de Difusão , Humanos , Voluntários Saudáveis , Imagem de Difusão por Ressonância Magnética/métodos , Imagem de Tensor de Difusão/métodos , Lobo Temporal/anatomia & histologia , Imageamento por Ressonância Magnética , Vias Visuais
5.
Brain Struct Funct ; 228(2): 677-685, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36786881

RESUMO

The relationship among brain structure, brain function, and behavior is of major interest in neuroscience, evolutionary biology, and psychology. This relationship is especially intriguing when considering hominoid-specific brain structures because they cannot be studied in widely examined models in neuroscience such as mice, marmosets, and macaques. The fusiform gyrus (FG) is a hominoid-specific structure critical for face processing that is abnormal in individuals with developmental prosopagnosia (DPs)-individuals who have severe deficits recognizing the faces of familiar people in the absence of brain damage. While previous studies have found anatomical and functional differences in the FG between DPs and NTs, no study has examined the shallow tertiary sulcus (mid-fusiform sulcus, MFS) within the FG that is a microanatomical, macroanatomical, and functional landmark in humans, as well as was recently shown to be present in non-human hominoids. Here, we implemented pre-registered analyses of neuroanatomy and face perception in NTs and DPs. Results show that the MFS was shorter in DPs than NTs. Furthermore, individual differences in MFS length in the right, but not left, hemisphere predicted individual differences in face perception. These results support theories linking brain structure and function to perception, as well as indicate that individual differences in MFS length can predict individual differences in face processing. Finally, these findings add to growing evidence supporting a relationship between morphological variability of late developing, tertiary sulci and individual differences in cognition.


Assuntos
Reconhecimento Facial , Humanos , Animais , Camundongos , Lobo Temporal/anatomia & histologia , Neuroanatomia , Cognição , Reconhecimento Visual de Modelos , Imageamento por Ressonância Magnética
6.
Oper Neurosurg (Hagerstown) ; 24(2): e92-e103, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36637312

RESUMO

BACKGROUND: Current approaches for mesial temporal lobe epilepsy may result in suboptimal seizure control and cognitive decline. An incomplete treatment of the epileptogenic zone and unnecessary violation of functional cortical and subcortical areas may contribute to suboptimal results. OBJECTIVE: To describe and test the anatomic feasibility of a novel endoscopic anterior transmaxillary (ATM) approach to the temporal lobe and to compare the described technique to other transfacial approaches. METHODS: Twenty-four cadaveric brain hemispheres fixed in formalin were used to study anterior temporal surface anatomy. Two additional hemispheres were fixed in formalin and then frozen for white matter dissections. Subsequently, bilateral dissections on 4 injected cadaveric heads were used to describe the endoscopic ATM approach and to evaluate various anterior endoscopic corridors for the temporal pole and mesial temporal lobe structures. RESULTS: The ATM approach was considered superior because of direct visualization of the temporal pole and natural alignment with the mesial temporal structures. The mean exposure corridor covered 49.1° in the sagittal plane and 66.2° in the axial plane. The ATM allowed direct access lateral to the maxillary and mandibular nerves with an anterior-posterior trajectory aligned to the longitudinal axis of the hippocampus formation, allowing for a selective amygdalohippocampectomy with preservation of the trigeminal branches and the lateral temporal neocortex. CONCLUSION: The ATM approach is anatomically feasible, providing a direct and selective approach for the temporal pole and mesial temporal lobe structures, with a substantial angle of visualization because of its direct alignment with the mesial temporal lobe structures.


Assuntos
Epilepsia do Lobo Temporal , Humanos , Epilepsia do Lobo Temporal/cirurgia , Tonsila do Cerebelo/anatomia & histologia , Lobo Temporal/cirurgia , Lobo Temporal/anatomia & histologia , Hipocampo/cirurgia , Hipocampo/anatomia & histologia , Cadáver
7.
Neuroimage ; 265: 119776, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36460275

RESUMO

The surface of the cerebral cortex is very convoluted, with a large number of folds, the cortical sulci. These folds are extremely variable from one individual to another, and this large variability is a problem for many applications in neuroscience and brain imaging. In particular, sulcal geometry (shape) and sulcal topology (branches, number of pieces) are very variable. "Plis de passages" (PPs) or "annectant gyri" can explain part of the topological variability, namely why sulci have a variable number of pieces across subjects. The concept of PPs was first introduced by Gratiolet (1854) to describe transverse gyri that interconnect both sides of a sulcus, that are frequently buried in the depth of sulci, and that are sometimes apparent on the cortical surface, hence seemingly interrupting the course of sulci and separating them in several pieces. Nevertheless, the difficulty of identifying PPs and the lack of systematic methods to automatically detect them has limited their use. However, based on a recent characterization of PPs in the superior temporal sulcus, we present here a method to automatically detect PPs in the superior temporal sulcus. Local morphology within the sulcus is characterized using cortical surface profiling, and the three-dimensional PP recognition problem is performed as a two-dimensional image classification problem with class-imbalance. This is solved by using an ensemble support vector machine model (EnsSVM) with a rebalancing strategy. Cross validation and quantitative experimental results on an external dataset show the effectiveness and robustness of our approach.


Assuntos
Córtex Auditivo , Lobo Temporal , Humanos , Lobo Temporal/diagnóstico por imagem , Lobo Temporal/anatomia & histologia , Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/anatomia & histologia , Lobo Occipital , Encéfalo , Aprendizado de Máquina , Imageamento por Ressonância Magnética/métodos
8.
Anat Rec (Hoboken) ; 306(8): 2030-2043, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36371781

RESUMO

The literature describing the complex anatomy of the middle cerebral artery (MCA), lenticulostriate arteries, and recurrent artery of Heubner, does not discuss the comparative anatomy of the cerebrum, MCA, the recurrent artery of Heubner, and the relationship of the MCA with the rhinal sulci. The entorhinal literature does not detail the comparative anatomic modification of the rhinal and endorhinal sulci, piriform lobe and the hippocampus's compressed positional change in the temporal lobe. This investigation's objectives were to analyze the comparative anatomic modifications of the cerebrum, the MCA, lenticulostriate arteries, recurrent artery of Heubner, olfactory tubercule, anterior perforate substance, rhinal sulcus, endorhinal sulcus, piriform lobe, entorhinal cortex, and hippocampus. Brain dissections of adult iguana, rabbit, sheep, cat, dog, macaque, human and human fetal specimens were analyzed. The MCA branches enter the striate nuclei via the endorhinal sulcus, with few branches present in the rhinal sulcus. Modifications of the cerebrum, with the development of gyri and sulci and opercula covering the insula, changes the linear surface configuration of the MCA into a tridimensional one. Similar changes are present in human fetal specimens. The cerebral neocortical expansion changes the position of the rhinal and endorhinal sulci, their relationship with the MCA, the size of the olfactory tubercule, the position and size of the piriform lobe, and the diagonal course of the lenticulostriates and recurrent artery of Heubner. The hippocampus becomes compressed in the inferomedial region of the human temporal lobe. The lenticulostriate arteries are likely the first developed component of the MCA.


Assuntos
Córtex Entorrinal , Artéria Cerebral Média , Adulto , Humanos , Animais , Cães , Coelhos , Ovinos , Córtex Entorrinal/anatomia & histologia , Anatomia Comparada , Hipocampo , Lobo Temporal/anatomia & histologia , Córtex Cerebral/anatomia & histologia
9.
Neurol Med Chir (Tokyo) ; 62(11): 502-512, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36130902

RESUMO

The sylvian fissure stem and its deep cisternal part (SDCP) consist mainly of the orbital gyrus (OG) and anterior medial portion of the temporal lobe. SDCP's adhesion has been found to make a trans-sylvian approach difficult due to the various patterns of adhesion. Thus, in this study, we aim to clarify the morphological features of the SDCP, and to guide a safe trans-sylvian approach. We retrospectively classified the morphology of the SDCP in 81 patients into 3 types (tight, moderate, loose type) according to the degree of adhesion of the arachnoid membrane and analyzed the morphological features of the OG and the temporal lobe using intraoperative video images. In addition, we have retrospectively measured each width of the SDCP's subarachnoid space at the three points (Point A, lateral superior portion; Point B, downward portion; Point C, medial inferior portion of SDCP) and analyzed their relationship to the degree of adhesion using the preoperative coronal three-dimensional computed tomography angiography (3D-CTA) images of 44 patients. As per the results, SDCP's adhesions were determined to be significantly tighter in cases with large OG and young cases. The temporal lobe had four surfaces (posterior, middle, anterior, and medial) that adhered to the OG in various patterns. The tighter the adhesion between the OG and each of the three distal surfaces of the temporal lobe, the narrower the width of the subarachnoid space at each point (A, B, C). Understanding of the morphological features of the SDCP, and estimating its adhesion preoperatively are useful in developing a surgical strategy and obtaining correct intraoperative orientation in the trans-sylvian approach.


Assuntos
Córtex Cerebral , Lobo Temporal , Humanos , Estudos Retrospectivos , Lobo Temporal/diagnóstico por imagem , Lobo Temporal/cirurgia , Lobo Temporal/anatomia & histologia , Lobo Frontal/cirurgia , Espaço Subaracnóideo
10.
Handb Clin Neurol ; 187: 3-16, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35964979

RESUMO

The idea of a temporal lobe separated from the rest of the hemisphere by reason of its unique structural and functional properties is a clinically useful artifact. While the temporal lobe can be safely defined as the portion of the cerebrum lodged in the middle cranial fossa, the pattern of its connections is a more revealing description of its functional subdivisions and specific contribution to higher cognitive functions. This chapter provides an historical overview of the anatomy of the temporal lobe and an updated framework of temporal lobe connections based on tractography studies of human and nonhuman primates and patients with brain disorders. Compared to monkeys, the human temporal lobe shows a relatively increased connectivity with perisylvian frontal and parietal regions and a set of unique intrinsic connections, which may have supported the evolution of working memory, semantic representation, and language in our species. Conversely, the decreased volume of the anterior (limbic) interhemispheric temporal connections in humans is related to a reduced reliance on olfaction and a partial transference of functions from the anterior commissure to the posterior corpus callosum. Overall the novel data from tractography suggest a revision of current dual stream models for visual and auditory processing.


Assuntos
Mapeamento Encefálico , Lobo Temporal , Animais , Corpo Caloso , Humanos , Vias Neurais/anatomia & histologia , Vias Neurais/diagnóstico por imagem , Lobo Parietal , Lobo Temporal/anatomia & histologia , Lobo Temporal/diagnóstico por imagem
11.
Handb Clin Neurol ; 187: 17-51, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35964970

RESUMO

The temporal cortex encompasses a large number of different areas ranging from the six-layered isocortex to the allocortex. The areas support auditory, visual, and language processing, as well as emotions and memory. The primary auditory cortex is found at the Heschl gyri, which develop early in ontogeny with the Sylvian fissure, a deep and characteristic fissure that separates the temporal lobe from the parietal and frontal lobes. Gyri and sulci as well as brain areas vary between brains and between hemispheres, partly linked to the functional organization of language and lateralization. Interindividual variability in anatomy makes a direct comparison between different brains in structure-functional analysis often challenging, but can be addressed by applying cytoarchitectonic probability maps of the Julich-Brain atlas. We review the macroanatomy of the temporal lobe, its variability and asymmetry at the macro- and the microlevel, discuss the relationship to brain areas and their microstructure, and emphasize the advantage of a multimodal approach to address temporal lobe organization. We review recent data on combined cytoarchitectonic and molecular architectonic studies of temporal areas, and provide links to their function.


Assuntos
Córtex Auditivo , Lobo Temporal , Encéfalo/anatomia & histologia , Lobo Frontal/anatomia & histologia , Humanos , Idioma , Lobo Temporal/anatomia & histologia
12.
Proc Natl Acad Sci U S A ; 119(28): e2118295119, 2022 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-35787056

RESUMO

The biological foundation for the language-ready brain in the human lineage remains a debated subject. In humans, the arcuate fasciculus (AF) white matter and the posterior portions of the middle temporal gyrus are crucial for language. Compared with other primates, the human AF has been shown to dramatically extend into the posterior temporal lobe, which forms the basis of a number of models of the structural connectivity basis of language. Recent advances in both language research and comparative neuroimaging invite a reassessment of the anatomical differences in language streams between humans and our closest relatives. Here, we show that posterior temporal connectivity via the AF in humans compared with chimpanzees is expanded in terms of its connectivity not just to the ventral frontal cortex but also to the parietal cortex. At the same time, posterior temporal regions connect more strongly to the ventral white matter in chimpanzees as opposed to humans. This pattern is present in both brain hemispheres. Additionally, we show that the anterior temporal lobe harbors a combination of connections present in both species through the inferior fronto-occipital fascicle and human-unique expansions through the uncinate and middle and inferior longitudinal fascicles. These findings elucidate structural changes that are unique to humans and may underlie the anatomical foundations for full-fledged language capacity.


Assuntos
Substância Branca , Animais , Mapeamento Encefálico/métodos , Humanos , Idioma , Vias Neurais/anatomia & histologia , Neuroanatomia , Pan troglodytes/anatomia & histologia , Lobo Temporal/anatomia & histologia , Lobo Temporal/diagnóstico por imagem , Substância Branca/anatomia & histologia , Substância Branca/diagnóstico por imagem
13.
Sci Rep ; 12(1): 1829, 2022 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-35115559

RESUMO

Brain systems dealing with multiple meanings of ambiguous stimuli are relatively well studied, while the processing of non-selected meanings is less investigated in the neurophysiological literature and provokes controversy between existing theories. It is debated whether these meanings are actively suppressed and, if yes, whether suppression characterizes any task that involves alternative solutions or only those tasks that emphasize semantic processing or the existence of alternatives. The current functional MRI event-related study used a modified version of the word fragment completion task to reveal brain mechanisms involved in implicit processing of the non-selected solutions of ambiguous fragments. The stimuli were pairs of fragmented adjectives and nouns. Noun fragments could have one or two solutions (resulting in two words with unrelated meanings). Adjective fragments had one solution and created contexts strongly suggesting one solution for ambiguous noun fragments. All fragmented nouns were presented twice during the experiment (with two different adjectives). We revealed that ambiguity resolution was associated with a reduced BOLD signal within several regions related to language processing, including the anterior hippocampi and amygdala and posterior lateral temporal cortex. Obtained findings were interpreted as resulting from brain activity inhibition, which underlies a hypothesized mechanism of suppression of non-selected solutions.


Assuntos
Tonsila do Cerebelo/fisiologia , Hipocampo/fisiologia , Reconhecimento Fisiológico de Modelo/fisiologia , Semântica , Lobo Temporal/fisiologia , Adulto , Tonsila do Cerebelo/anatomia & histologia , Mapeamento Encefálico , Compreensão/fisiologia , Feminino , Hipocampo/anatomia & histologia , Humanos , Idioma , Imageamento por Ressonância Magnética , Masculino , Tempo de Reação/fisiologia , Lobo Temporal/anatomia & histologia , Vocabulário
14.
Ann Anat ; 241: 151894, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35085705

RESUMO

PURPOSE: A fundamental feature in interpreting gross or neuroimaging brain anatomy is reliance on an assumed high degree of morphologic symmetry in bilateral hemispheres. However, the normal brain is not perfectly symmetrical, and subtle inherent structural asymmetries could potentially confound appreciation of pathology-induced asymmetry or how a given brain asymmetry can relate to its function. MATERIAL AND METHODS: We review the literature and provide a brief overview of structural asymmetries in normal brain anatomy. RESULTS: Brain structural asymmetries are either rotational or pure right-left asymmetries, and many are a consequence of unique features linked to the use of human language. Yakovlevian torque is the tendency of the right hemisphere to rotate slightly forward relative to the left, which may make the right frontal lobe bigger and wider, and the left occipital lobe wider and protrude rightward. This makes the left Sylvian fissure longer and flatter, resulting in a larger planum temporale. We also discuss right-left asymmetries in the cortex, white matter structures, deep gray nuclei, and lateral ventricles. Brain asymmetries are not random but result from distinct patterns in structural design that confer evolutionary functional advantages. CONCLUSION: Minor brain asymmetries are important and should be accounted for as they can be connected to function, and like individual variability, are essential for evolution. This overview will help understand structural brain asymmetries for improved diagnostic neuroimaging interpretation, constructing symmetry-based paradigms for automatic localization, segmentation of brain lesions, and as a reference for studies on possible implications of excessive asymmetry and altered laterality in cognitive, neurological, and psychiatric disorders.


Assuntos
Encéfalo , Lateralidade Funcional , Encéfalo/anatomia & histologia , Encéfalo/diagnóstico por imagem , Lobo Frontal , Humanos , Idioma , Imageamento por Ressonância Magnética , Lobo Temporal/anatomia & histologia
15.
World Neurosurg ; 157: e156-e165, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34619404

RESUMO

OBJECTIVE: The white fiber and gross anatomy relevant for performing amygdalohippocampectomy through the middle temporal gyrus approach for mesial temporal sclerosis has been depicted by white fiber dissection. METHODS: Three previously frozen and formalin fixed cerebral hemispheres were studied. The Klingler method of fiber dissection was used to study the anatomy. The primary tools used were hand-made wooden spatulas, forceps, and microscissors. The anatomy of the amygdala and hippocampus and the landmarks for performing the disconnection during epilepsy surgery are presented. The white fibers at risk during the middle temporal gyrus approach were studied. RESULTS: The white fiber tracts at risk during the middle temporal gyrus approach for epilepsy surgery are the fibers of the inferior frontooccipital fasciculus, temporal extension of the anterior commissure, Meyer loop of the optic radiation, and uncinate fasciculus. On the basis of our anatomic dissections, we present a novel entry point into the temporal horn, potentially minimizing injury to the fibers of the sagittal stratum. We also propose novel landmarks to perform the amygdala disconnection in mesial temporal sclerosis. CONCLUSIONS: The middle temporal gyrus is a commonly used approach to perform temporal lobectomy and amygdalohippocampectomy for patients with mesial temporal sclerosis. The anatomy relevant to the approach as presented will aid while performing epilepsy surgery.


Assuntos
Tonsila do Cerebelo/cirurgia , Hipocampo/cirurgia , Lobo Temporal/cirurgia , Substância Branca/cirurgia , Adulto , Tonsila do Cerebelo/anatomia & histologia , Tonsila do Cerebelo/patologia , Hipocampo/anatomia & histologia , Hipocampo/patologia , Humanos , Lobo Temporal/anatomia & histologia , Lobo Temporal/patologia , Substância Branca/anatomia & histologia , Substância Branca/patologia
16.
J Neurophysiol ; 126(4): 1289-1309, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34379536

RESUMO

The connectivity among architectonically defined areas of the frontal, parietal, and temporal cortex of the macaque has been extensively mapped through tract-tracing methods. To investigate the statistical organization underlying this connectivity, and identify its underlying architecture, we performed a hierarchical cluster analysis on 69 cortical areas based on their anatomically defined inputs. We identified 10 frontal, four parietal, and five temporal hierarchically related sets of areas (clusters), defined by unique sets of inputs and typically composed of anatomically contiguous areas. Across the cortex, clusters that share functional properties were linked by dominant information processing circuits in a topographically organized manner that reflects the organization of the main fiber bundles in the cortex. This led to a dorsal-ventral subdivision of the frontal cortex, where dorsal and ventral clusters showed privileged connectivity with parietal and temporal areas, respectively. Ventrally, temporofrontal circuits encode information to discriminate objects in the environment, their value, emotional properties, and functions such as memory and spatial navigation. Dorsal parietofrontal circuits encode information for selecting, generating, and monitoring appropriate actions based on visual-spatial and somatosensory information. This organization may reflect evolutionary antecedents, in which the vertebrate pallium, which is the ancestral cortex, was defined by a ventral and lateral olfactory region and a medial hippocampal region.NEW & NOTEWORTHY The study of cortical connectivity is crucial for understanding brain function and disease. We show that temporofrontal and parietofrontal networks in the macaque can be described in terms of circuits among clusters of areas that share similar inputs and functional properties. The resulting overall architecture described a dual subdivision of the frontal cortex, consistent with the main cortical fiber bundles and an evolutionary trend that underlies the organization of the cortex in the macaque.


Assuntos
Lobo Frontal , Macaca , Rede Nervosa , Lobo Parietal , Lobo Temporal , Animais , Análise por Conglomerados , Lobo Frontal/anatomia & histologia , Lobo Frontal/fisiologia , Macaca/anatomia & histologia , Macaca/fisiologia , Rede Nervosa/anatomia & histologia , Rede Nervosa/fisiologia , Lobo Parietal/anatomia & histologia , Lobo Parietal/fisiologia , Lobo Temporal/anatomia & histologia , Lobo Temporal/fisiologia
17.
PLoS One ; 16(6): e0252178, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34166386

RESUMO

Opposing genetic and cultural-social explanations for the origin of language are currently the focus of much discussion. One of the functions linked to the longitudinal fascicle is language, which links Wernicke's area and Broca's area in the brain, and its size should indicate the brain increase in the evolution. Sapajus is a New World primate genus with high cognition and advanced tool use similar to that of chimpanzees. A study of the gross anatomy of the longitudinal fascicle of Sapajus using Kingler's method found it to differ from other studied primates, such as macaques and chimpanzees, mainly because its fibers join the cingulate fascicle. As in other non-human primates, the longitudinal fascicle of Sapajus does not reach the temporal lobe, which could indicate a way of separating these fascicles to increase white matter in relation to individual function. The study of anatomical structures seems very promising for understanding the basis of the origin of language. Indeed, socio-historical-cultural philosophy affirms the socio-cultural origin of speech, although considering the anatomical structures behind it working as a functional system.


Assuntos
Encéfalo/anatomia & histologia , Córtex Cerebral/anatomia & histologia , Vias Neurais/anatomia & histologia , Sapajus/anatomia & histologia , Lobo Temporal/anatomia & histologia , Substância Branca/anatomia & histologia , Animais , Encéfalo/fisiologia , Mapeamento Encefálico , Córtex Cerebral/fisiologia , Feminino , Masculino , Vias Neurais/fisiologia , Sapajus/fisiologia , Lobo Temporal/fisiologia , Substância Branca/fisiologia
18.
Psychophysiology ; 58(8): e13841, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34159607

RESUMO

The neural substrates that contribute to creative thinking through the recruitment of semantic memory structures remain largely unknown. This study sought to investigate the properties of semantic networks using a semantic judgment rating task at the individual level and explore the relationship among creative abilities, the topological properties of semantic networks, and their underlying brain structures. We first used a semantic judgment rating to assess individual semantic networks and computed their topological properties. The analysis confirmed a significant correlation between the creative thinking abilities assessed by an alternate uses task and all three topological properties. In addition, voxel-based morphometry was employed to assess the neural correlates of gray matter volume (GMV) related to different topological properties of the semantic network. Results revealed a positive correlation between global efficiency and the left temporal pole cortex, considered to be involved in semantic information transmission and processing. Furthermore, mediation analysis found that the global efficiency of the individual semantic network mediated the association between the left temporal pole GMV and creative thinking, showing that the relationship between left temporal pole GMV and creative thinking may be affected by the semantic networks. To the best of our knowledge, this study is the first to combine a behavioral investigation of semantic networks with magnetic resonance imaging to shed light on the cerebral structural basis of semantic memory networks, in addition to their relationship to creativity.


Assuntos
Criatividade , Substância Cinzenta , Rede Nervosa , Lobo Temporal , Pensamento/fisiologia , Adulto , Feminino , Substância Cinzenta/anatomia & histologia , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/fisiologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Rede Nervosa/anatomia & histologia , Rede Nervosa/diagnóstico por imagem , Rede Nervosa/fisiologia , Semântica , Lobo Temporal/anatomia & histologia , Lobo Temporal/diagnóstico por imagem , Lobo Temporal/fisiologia , Adulto Jovem
19.
J Neurophysiol ; 125(5): 1851-1882, 2021 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-33656951

RESUMO

Primate visual cortex consists of dozens of distinct brain areas, each providing a highly specialized component to the sophisticated task of encoding the incoming sensory information and creating a representation of our visual environment that underlies our perception and action. One such area is the medial superior temporal cortex (MST), a motion-sensitive, direction-selective part of the primate visual cortex. It receives most of its input from the middle temporal (MT) area, but MST cells have larger receptive fields and respond to more complex motion patterns. The finding that MST cells are tuned for optic flow patterns has led to the suggestion that the area plays an important role in the perception of self-motion. This hypothesis has received further support from studies showing that some MST cells also respond selectively to vestibular cues. Furthermore, the area is part of a network that controls the planning and execution of smooth pursuit eye movements and its activity is modulated by cognitive factors, such as attention and working memory. This review of more than 90 studies focuses on providing clarity of the heterogeneous findings on MST in the macaque cortex and its putative homolog in the human cortex. From this analysis of the unique anatomical and functional position in the hierarchy of areas and processing steps in primate visual cortex, MST emerges as a gateway between perception, cognition, and action planning. Given this pivotal role, this area represents an ideal model system for the transition from sensation to cognition.


Assuntos
Cognição/fisiologia , Macaca/fisiologia , Percepção de Movimento/fisiologia , Sensação/fisiologia , Lobo Temporal/fisiologia , Córtex Visual/fisiologia , Animais , Humanos , Lobo Temporal/anatomia & histologia , Córtex Visual/anatomia & histologia
20.
J Chem Neuroanat ; 113: 101925, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33582250

RESUMO

Historically, the anterior part of the temporal lobe was labelled as a unique structure named Brain Area 38 by Brodmann or Temporopolar Area TG by Von Economo, but its functions were unknown at that time. Later on, a few studies proposed to divide the temporal pole in several different subparts, based on distinct cytoarchitectural structure or connectivity patterns, while a still growing number of studies have associated the temporal pole with many cognitive functions. In this review, we provide an overview of the temporal pole anatomical and histological structure and its various functions. We performed a literature review of articles published prior to September 30, 2020 that included 112 articles. The temporal pole has thereby been associated with several high-level cognitive processes: visual processing for complex objects and face recognition, autobiographic memory, naming and word-object labelling, semantic processing in all modalities, and socio-emotional processing, as demonstrated in healthy subjects and in patients with neurological or psychiatric diseases, especially in the field of neurodegenerative disorders. A good knowledge of those functions and the symptoms associated with temporal pole lesions or dysfunctions is helpful to identify these diseases, whose diagnosis may otherwise be difficult.


Assuntos
Memória/fisiologia , Cognição Social , Lobo Temporal/anatomia & histologia , Animais , Mapeamento Encefálico , Humanos , Vias Neurais/anatomia & histologia , Vias Neurais/fisiologia , Lobo Temporal/fisiologia
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