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Motor intention is a high-level brain function related to planning for movement. Although studies have shown that motor intentions can be decoded from brain signals before movement execution, it is unclear whether intentions relating to mental imagery of movement can be decoded. Here, we investigated whether differences in spatial and temporal patterns of brain activation were elicited by intentions to perform different types of motor imagery and whether the patterns could be used by a multivariate pattern classifier to detect such differential intentions. The results showed that it is possible to decode intentions before the onset of different types of motor imagery from functional MR signals obtained from fronto-parietal brain regions, such as the premotor cortex and posterior parietal cortex, while controlling for eye movements and for muscular activity of the hands. These results highlight the critical role played by the aforementioned brain regions in covert motor intentions. Moreover, they have substantial implications for rehabilitating patients with motor disabilities.

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The parietal lobe, constituting approximately 20% of the human brain, comprises two main regions: the somatosensory cortex and the posterior parietal cortex. The former is responsible for receiving and processing information from the organism itself or its external environment, while the latter performs concurrent summaries and higher cognitive functions. The present study seeks to integrate modern research findings with Luria's previous discoveries in order to gain a nuanced understanding of the roles assigned to the parietal lobe as well as its lateralization differences.

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We studied the organization of the inferior parietal cortex (IPC) in five capuchin monkey (6 hemispheres) using cytoarchitectonic (Nissl), myeloarchitectonic (Gallyas), and immune-architectonic (SMI-32 monoclonal antibody) techniques. We partitioned the IPC into five distinct areas: PFG, PG, Opt, PFop, and PGop. Since we used parasagittal sections, we were not able to study area PF due to its far lateral position, which yielded slices that were tangential to the pial surface. Areas PFG, PG, and Opt were in the convexity close to the lateral sulcus, while PFop and PGop were positioned more posteriorly, in the opercular region of IPC. Of all the five regions, area Opt was the one most similar to its analogue in the macaque, especially as revealed with SMI-32 staining. Namely, in both primate species area Opt showed a low density of large pyramidal neurons. Additionally, the apical dendrites of these neurons were sparse and vertically orientated, resembling columns. We also found area PG to be similar: both species exhibited cell body layers with a radial arrangement. On the other hand, Nissl staining revealed area PFG to be architectonically different between New and Old-World monkeys: PFG in the capuchin showed a comparatively higher cell density than in macaques, especially in layers II and IV. These results suggest that evolution may have enabled the functional specialization of these brain regions based on behavioral demands of upper limb use. The small differences in the IPC of the two primates may be linked to interspecies variability.

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Gerstmann Syndrome (GS) is a rare neurological condition described as a group of cognitive changes corresponding to a tetrad of symptoms comprising agraphia, acalculia, right-left disorientation and finger agnosia. It is known that some specific brain lesions may lead to such findings, particularly when there is impairment of the angular gyrus and adjacent structures. In addition, the possibility of disconnection syndrome should be considered in some cases. The purpose of this article is to report a case of a young, cardiac patient, non-adherent to treatment, who presented with a stroke in which transient clinical symptoms were compatible with the tetrad of GS. The case report is followed by a discussion and brief review of the relevant literature.

A síndrome de Gerstmann (SG) é uma condição neurológica rara, caracterizada por um grupo de alterações cognitivas que correspondem a uma tétrade composta por agrafia, acalculia, desorientação direita-esquerda e agnosia para dedos. Sabe-se que certas lesões encefálicas específicas podem levar a tais achados, particularmente quando ocorre acometimento do giro angular e estruturas adjacentes. Além disso, a possibilidade de síndrome de desconexão deve ser considerada em alguns casos. O propósito deste artigo é relatar o caso de um paciente jovem cardiopata e não aderente ao tratamento que se apresentou com uma síndrome encéfalo-vascular associada a alterações clínicas transitórias compatíveis com a tétrade da SG. Este relato de caso é acompanhado de discussão e breve revisão de dados pertinentes da literatura.

RESUMO

ABSTRACT Gerstmann Syndrome (GS) is a rare neurological condition described as a group of cognitive changes corresponding to a tetrad of symptoms comprising agraphia, acalculia, right-left disorientation and finger agnosia. It is known that some specific brain lesions may lead to such findings, particularly when there is impairment of the angular gyrus and adjacent structures. In addition, the possibility of disconnection syndrome should be considered in some cases. The purpose of this article is to report a case of a young, cardiac patient, non-adherent to treatment, who presented with a stroke in which transient clinical symptoms were compatible with the tetrad of GS. The case report is followed by a discussion and brief review of the relevant literature.

RESUMO A síndrome de Gerstmann (SG) é uma condição neurológica rara, caracterizada por um grupo de alterações cognitivas que correspondem a uma tétrade composta por agrafia, acalculia, desorientação direita-esquerda e agnosia para dedos. Sabe-se que certas lesões encefálicas específicas podem levar a tais achados, particularmente quando ocorre acometimento do giro angular e estruturas adjacentes. Além disso, a possibilidade de síndrome de desconexão deve ser considerada em alguns casos. O propósito deste artigo é relatar o caso de um paciente jovem cardiopata e não aderente ao tratamento que se apresentou com uma síndrome encéfalo-vascular associada a alterações clínicas transitórias compatíveis com a tétrade da SG. Este relato de caso é acompanhado de discussão e breve revisão de dados pertinentes da literatura.

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Gender dysphoria (GD) (DSM-5) or transsexualism (ICD-10) refers to the marked incongruity between the experience of one's gender and the sex at birth. In this case report, we describe the use of LSD as a triggering factor of confusion in the gender identity of a 39-year-old male patient, with symptoms of psychosis and 25 years of substance abuse, who sought psychiatric care with the desire to undergo sex reassignment surgery. The symptoms of GD/psychosis were resolved by two therapeutic measures: withdrawal of psychoactive substances and use of a low-dose antipsychotic. We discuss the hypothesis that the superior parietal cortical area may be an important locus for body image and that symptoms of GD may be related to variations underlying this brain region. Finally, this case report shows that some presentations of GD can be created by life experience in individuals who have underlying mental or, synonymously, neurophysiological abnormalities.

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A vivência de maus tratos na infância é apontada como um fator de risco para o desenvolvimento de comportamentos antissociais e traços psicopáticos. Estudos sugerem alterações estruturais de substância branca (SB) cerebral em vítimas de maus tratos, que podem estar subjacentes a sintomas psiquiátricos e dificuldades cognitivas. OBJETIVO: Investigar o comportamento social de adolescentes vítimas de maus tratos (A-VMT), através da comparação de suas habilidades sociais e traços de psicopatia com um grupo controle (GC), e de possíveis correlações destas medidas com os diferentes tipos de maus tratos e com o volume de SB cerebral. MÉTODO: Foram avaliados 67 A-VMT e 41 adolescentes do GC através do Questionário de Traumas na Infância (QUESI), da Psychopathy Checklist Youth Version (PCL-YV) e do Inventário de Habilidades Sociais para Adolescentes (IHSA). Também foram adquiridas imagens anatômicas cerebrais através de equipamento de ressonância magnética (1,5T Siemens Sonata) e realizadas análises de morfometria baseada em voxels (VBM). RESULTADOS: Os A-VMT apresentaram maior intensidade de traços psicopáticos e mais déficits de habilidades sociais que o GC. A negligência emocional foi a forma de maus tratos que mais influenciou a presença de traços de psicopatia e que mais associou-se a prejuízos de habilidades sociais específicas. O volume de SB de regiões do hemisfério esquerdo (giro angular, precuneus e lobo parietal inferior) correlacionouse negativamente com o fator afetivo da PCL:YV. Além disso, foram encontradas correlações positivas entre o volume de SB de regiões de hemisfério direito com fatores de psicopatia: o volume do lobo parietal superior direito correlacionou-se com características interpessoais e o do giro pré-central com o fator antissocial. CONCLUSÃO: Os A-VMT apresentaram déficits do comportamento social quando comparados ao GC. O volume de SB de áreas cerebrais envolvidas no processamento de informações sociais...

Child maltreatment is considered a risk factor for the development of antisocial behaviors and psychopathic traits. Studies suggest that specific white matter tracts may be vulnerable to child maltreatment and their alterations can be associated with psychiatric symptoms and cognitive deficits. Aim: Compare social skills and psychopathic traits between maltreated adolescents (MTA) and a control group, as well as their possible correlations with different types of maltreatment and white matter volumes.. Method: The sample was composed by 67 MTA and 41 youths from the CG. Brain images were acquired by magnetic resonance imaging equipment (1,5T Siemens Sonata) for voxel-based morphometry analyses. The clinical evaluation was carried out using Childhood Trauma Inventory (CTQ), Social Skills Inventory for Adolescents (SSIA) and The Hare Psychopathy Checklist: Youth Version (PCL:YV). Results: MTA presented more psychopathic traits and social skills deficits than the CG. Emotional neglect was the only maltreatment subtype with significant effect on psychopathic traits, and it was correlated with specific social skills deficits. The white matter volumes of left hemisphere regions (angular gyrus, precuneus and inferior parietal lobe) were negatively correlated with PCL:YV affective factor scores. Moreover, positive correlations between white matter volume of right hemisphere areas (superior parietal lobe and precentral gyrus) and specific psychopathic traits (antisocial and interpersonal) were found. Conclusion: MTA presented social deficits when compared to CG. The white matter volume of brain areas associated with social information processing and emotion recognition was correlated with specific psychopathic traits. Child maltreatment may contribute to social cognition deficits and predispose this vulnerable population to psychopathic traits...

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El procesamiento visual en el contexto de la neuropsicología exige la articulación de distintos niveles de análisis. Esto hace que el estudio de la visión se encuentre permeado por el avance en distintas disciplinas lo cual plantea como reto a la neuropsicología la construcción de un marco conceptual y de organización cerebral que permita la articulación de los vastos y distintos conocimientos que en la actualidad se tienen sobre el tema. Por tal motivo el presente artículo tiene como objetivo revisar los aportes de los principales modelos dicotómicos del procesamiento visual empleados en neuropsicología para detenernos con mayor detalle en la participación del Lóbulo Parietal Posterior y los retos que plantea a dichos modelos.

Visual processing requires, from a neuropsychological view, the integration of different analysis levels. This makes visual studies dependent on the advances produced by different scientific disciplines, leading into an increasing and comprehensive conceptual demand as well as more consistent brain functioning models. Thus, the aim of this article is to review the most outstanding dichotomic visual processing models used in neuropsychology, so as to painstakingly analyze the role of the Posterior Parietal Lobe and the risks taken by those different models.

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THIS ARTICLE DISCUSSES THE POSSIBLE HOMOLOGIES BETWEEN THE HUMAN LANGUAGE NETWORKS AND COMPARABLE AUDITORY PROJECTION SYSTEMS IN THE MACAQUE BRAIN, IN AN ATTEMPT TO RECONCILE TWO EXISTING VIEWS ON LANGUAGE EVOLUTION: one that emphasizes hand control and gestures, and the other that emphasizes auditory-vocal mechanisms. The capacity for language is based on relatively well defined neural substrates whose rudiments have been traced in the non-human primate brain. At its core, this circuit constitutes an auditory-vocal sensorimotor circuit with two main components, a "ventral pathway" connecting anterior auditory regions with anterior ventrolateral prefrontal areas, and a "dorsal pathway" connecting auditory areas with parietal areas and with posterior ventrolateral prefrontal areas via the arcuate fasciculus and the superior longitudinal fasciculus. In humans, the dorsal circuit is especially important for phonological processing and phonological working memory, capacities that are critical for language acquisition and for complex syntax processing. In the macaque, the homolog of the dorsal circuit overlaps with an inferior parietal-premotor network for hand and gesture selection that is under voluntary control, while vocalizations are largely fixed and involuntary. The recruitment of the dorsal component for vocalization behavior in the human lineage, together with a direct cortical control of the subcortical vocalizing system, are proposed to represent a fundamental innovation in human evolution, generating an inflection point that permitted the explosion of vocal language and human communication. In this context, vocal communication and gesturing have a common history in primate communication.

RESUMO

This strict localizationism had and still has its importance for the development of Neurosciences, since the analysis of changes in mental processes resulting from brain damage became the basis for understanding the brain organization. The human parietal cortex is a highly differentiated structure, consisting of citoarchitectonically defined subareas that are connected to other cortical and subcortical areas. Patients with lesions in the parietal cortex develop various types of neuropsychological manifestations, depending on the specific location of the lesion and the corresponding hemisphere and these lesions in this lobe do not cause modal specific disturbances. The establishment of homologies between the parietal region in humans and primates can be of great contribution in trying to unravel the various functions and complexity of this area.

O localizacionismo estrito teve e ainda tem a sua importância para o desenvolvimento da Neurociência, uma vez que a análise de mudanças nos processos mentais resultantes de danos cerebrais se tornou a base para a compreensão da organização cerebral. O córtex parietal humano é uma estrutura altamente diferenciada, composta por subáreas histologicamente definidas que estão ligadas a outras áreas corticais e subcorticais. Pacientes com lesões no córtex parietal desenvolvem vários tipos de manifestações neuropsicológicas, dependendo do local específico da lesão e do hemisfério correspondente, mas estas lesões não causam perturbações modais específicas. O estabelecimento de homologias entre a região parietal em seres humanos e os primatas podem ser de grande contribuição na tentativa de desvendar as diversas funções e complexidade desta área.

Assuntos

RESUMO

This strict localizationism had and still has its importance for the development of Neurosciences, since the analysis of changes in mental processes resulting from brain damage became the basis for understanding the brain organization. The human parietal cortex is a highly differentiated structure, consisting of citoarchitectonically defined subareas that are connected to other cortical and subcortical areas. Patients with lesions in the parietal cortex develop various types of neuropsychological manifestations, depending on the specific location of the lesion and the corresponding hemisphere and these lesions in this lobe do not cause modal specific disturbances. The establishment of homologies between the parietal region in humans and primates can be of great contribution in trying to unravel the various functions and complexity of this area.

O localizacionismo estrito teve e ainda tem a sua importância para o desenvolvimento da Neurociência, uma vez que a análise de mudanças nos processos mentais resultantes de danos cerebrais se tornou a base para a compreensão da organização cerebral. O córtex parietal humano é uma estrutura altamente diferenciada, composta por subáreas histologicamente definidas que estão ligadas a outras áreas corticais e subcorticais. Pacientes com lesões no córtex parietal desenvolvem vários tipos de manifestações neuropsicológicas, dependendo do local específico da lesão e do hemisfério correspondente, mas estas lesões não causam perturbações modais específicas. O estabelecimento de homologias entre a região parietal em seres humanos e os primatas podem ser de grande contribuição na tentativa de desvendar as diversas funções e complexidade desta área.