Cerebral cortex最新文献

The inhibitory effect of interhemispheric signal propagation (ISP) is believed to be aligned with GABAB receptor mediated inhibitory neurotransmission and related to interhemispheric connectivity. Repetitive Transcranial magnetic stimulation (rTMS) is a safe and potent strategy for altering brain connectivity. However, it remains unclear if rTMS modulates ISP. With pretreatment of baclofen, a GABAB receptor agonist, this study characterized rTMS effects on ISP and the influence of GABAB receptor neurotransmission. ISP was measured with TMS and electroencephalography co-registration (TMS-EEG). Excitatory rTMS (> 5 Hz) was found to increase interhemispheric inhibition indexed by ISP. This effect was reduced by baclofen pretreatment, potentially reflecting competition for GABAB receptors neurotransmission between baclofen and rTMS. Beyond evoked potentials, our data also identified TMS-evoked gamma oscillation as a reliable indicator of intracortical inhibition. These novel findings help to clarify the effects of rTMS on interhemispheric connectivity, which may help to optimize rTMS treatments for various psychiatric disorders.

Breathing not only sustains life but also interacts with emotional states. Mounting evidence suggests that subtle variations in respiratory patterns-including their neural underpinnings-may serve as sensitive indicators of affective processes, yet the specific phases of spontaneous breathing have rarely been studied in detail. Here, we present a cross-sectional, exploratory investigation combining high-temporal-resolution respiratory measures, resting-state magnetoencephalography data, and psychological assessments in 46 healthy adults. Our analysis distinguishes three distinct phases-inspiration, expiration, and the brief but functionally significant post-expiratory pause (PEP). By correlating time-averaged Salience Network connectivity with aggregate respiratory metrics, we identify trait-level associations specific to the PEP in beta and gamma frequencies. Individuals with longer and more variable PEPs show distinct connectivity patterns associated with heightened depression and reduced life satisfaction. Connectivity patterns involving the right insula, bilateral anterior cingulate cortex, and left amygdala show robust correlations with these affective parameters, suggesting that this brief respiratory interval may serve as a window into interoceptive and emotional processing. Our findings highlight the overlooked role of the PEP in capturing meaningful interactions between respiration, neural circuits, and psychological well-being.

Gradients across microstructure, macro-connectivity, and gene expression scales have been identified in the primate brain, offering a continuous perspective to explore regional heterogeneity. The macaque insula, with its extensive connections with other cortical regions and involvement in diverse functions, exhibits gradient transitions at the microstructural level. However, the gradients of macroscopic structural connectivity (SC) and its relationship with gene expression in the macaque insula remain unclear. We hypothesized that SC gradients are closely associated with gene expression, driving insular parcellation. To test this, we analyzed high-resolution diffusion-weighted MR imaging alongside spatially aligned proteomic data. Our findings revealed a rostrocaudal organization of the dominant SC gradient in the macaque insula, leading to the identification of a four-subregion pattern within the insula based on the first two SC gradients. Proteomic profiles strongly correlated with the dominant SC gradient and the clustering of proteomic similarity aligned with the four-subregion pattern. Notably, the dominant SC gradient more effectively captured spatial protein expression variations than T1w/T2w and cortical thickness maps. Overall, this study demonstrated that the SC gradient analysis revealed a four-subregion pattern of parcellation aligned with the spatial distribution of proteomic profiles along the rostro-caudal axis.

The organization of the human cerebral cortex during fetal development is regulated by multiple processes, including neurogenesis and neuronal migration, which are essential for cortical expansion and folding patterns. According to the radial unit hypothesis, neurons originate in the germinal zone and migrate radially along the radial glial scaffolds to reach the cortical plate. However, the spatial distributions of these scaffolds and their roles in cortical folding remain unclear. Consequently, a computational model was developed to simulate virtual scaffolds extending from the cerebral ventricular surface to the white matter, incorporating region-specific neurogenic potential. The results demonstrate dense scaffold distribution in the perisylvian region, where complex cortical folding emerges, suggesting that differences in scaffold distribution contribute to region-specific cortical expansion. Notably, increased neuron influx along the scaffolds in the perisylvian region may contribute to early volumetric growth, potentially influencing Sylvian fissure formation. These findings align with previous reports that demonstrate distinct developmental patterns in this region. Being an accurate representation of radial migration pathways, this model provides a framework for integrating tangential migration of inhibitory neurons, refining scaffold distribution estimates, and quantifying early cortical development, offering insights into neurogenetic regional variations, scaffold architecture, and cortical folding in the human fetal brain.

We investigated the role of glutamatergic and GABAergic neurotransmissions within the rostral-posterior insular cortex (rpIC) and caudal-posterior IC (cpIC) subregions of the posterior IC (pIC) in cardiovascular responses and local neuronal activation evoked by acute restraint stress in male rats. We identified that treatment of the rpIC with a cocktail containing the GABAA receptor antagonist SR95531 and the GABAB receptor antagonist CGP35348 enhanced restraint-evoked tachycardia, whereas the same pharmacological approach in the cpIC decreased this response. Treatment of the rpIC with the nonselective ionotropic glutamate receptors antagonist kynurenic acid decreased the drop in tail skin temperature, and GABA receptor antagonism caused an opposite effect. Restraint increased Fos-positive cells in rpIC and cpIC, and local treatment with the glutamate receptor antagonism decreased this effect in both subregions. These data suggest a site-specific control of stress-evoked tachycardia by GABAergic mechanisms in the pIC. Moreover, sympathetically-mediated cutaneous vasoconstriction is specifically controlled by rpIC through opposite role of glutamatergic (facilitatory) and GABAergic (inhibitory) neurotransmissions.

Perceiving specific emotions from others' faces is a crucial ability for flexible and adaptive interaction, but the role of emotion concepts and categories in this perception has been controversial. The present study aims to investigate the precise time course of emotion concepts and categories involved in facial emotion perception. We conducted a behavioral task of conceptual similarity rating for emotional words, and emotion categorization tasks for emotional words and faces while recording electroencephalographic signals. We also performed a representational similarity analysis to assess the degree of correspondence between the representations of emotion concepts and categories with emotional faces over time. The results showed that the behavioral representations of emotion categories and concepts were successively correlated with the neural representations of the late processing stage for emotional faces at ~ 600-800 ms and ~800-1,000 ms, respectively. Furthermore, the representation of visual features of emotional faces was correlated with the neural representation of the early processing stage for faces (120-160 ms). Together, these results suggest that there is a temporal hierarchy in facial emotion perception that proceeds from visual to emotionally categorial to conceptual feature processing, providing electrophysiological evidence in support of basic emotion theory.

The ventral visual stream has undergone extensive reorganization within the primate lineage. While some work has examined restructuring of the ventral prefrontal cortical gray matter across primates, comparative studies of white matter connectivity are lacking primarily due to difficulties in data acquisition and processing. Here, we present a data-driven approach to the study of white matter connectivity using postmortem diffusion magnetic resonance imaging (MRI) data. With this approach, we reconstruct anterior temporal-frontal and occipitotemporal-frontal connections across 2 anthropoids and 1 strepsirrhine: the rhesus macaque, the black-capped squirrel monkey, and the ring-tailed lemur. We find that the anthropoids exhibit more dorsal prefrontal innervation of these ventral visual connections. This study supports the hypothesis that anthropoid primates underwent extensive reorganization of both gray and white matter during their emergence as visual foragers in a complex ecological niche. The data-driven techniques presented here enable further research on white matter connectivity in previously understudied species.

Autism spectrum disorder (ASD) is a complex neurodevelopmental condition characterized by social communication deficits and repetitive behaviors. Current neuroimaging-based diagnostic methods often rely on functional connectivity features extracted from a single perspective, either low-order interactions or high-order co-fluctuations, limiting their capacity to capture the hierarchical and dynamic properties of brain networks. We propose ViT-CMN, a novel ASD diagnosis framework that integrates multilevel dynamic connectivity information from both low-order and high-order perspectives. First, dynamic functional connectivity networks are constructed using a sliding window approach to capture temporal variations. To enrich data diversity, a temporal reorganization-based augmentation strategy is introduced, which generates additional dynamic sequences by shifting their starting time points. For each sequence, seventh-order central moment features are extracted to enhance statistical stability over time. These multiview features are then structurally reorganized via a jigsaw-style fusion strategy into a unified 2D representation. This fused input is modeled using a Vision Transformer (ViT) to extract discriminative representations across spatial and hierarchical dimensions through self-attention mechanisms. Experiments on the autism brain imaging data exchange (ABIDE) dataset demonstrate that ViT-CMN outperforms existing baseline methods, achieving a top classification accuracy of 79.8%. The model also successfully identifies ASD-related brain regions that align with known neuropathological findings. ViT-CMN effectively addresses the limitation of single-view modeling in previous studies by structurally fusing heterogeneous dynamic features into a ViT-compatible form. The proposed approach provides a powerful and interpretable solution for ASD diagnosis, with strong potential for broader applications in neuroimaging-based disorder classification.

Visual working memory is crucial for goal-directed thoughts and behaviors. However, it is not clear how goals modulate working memory maintenance, as previous models often considered stimulus encoding to be the endpoint of goal-directed control. To address this gap, eighty adults performed delayed estimation tasks while their brain activity was recorded using electroencephalography. In each trial, participants memorized three visual gratings varying in orientation and location and were instructed which attribute to recall. Based on recall success, trials were classified as successful or unsuccessful. We examined the effects of task instructions and their behavioral relevance using event-related potentials and multivariate pattern analysis during encoding and maintenance. The orientation task elicited larger contralateral delay activity than the location task. Moreover, the two tasks were decodable from brain patterns during the maintenance phase, and these patterns did not generalize to the encoding phase, suggesting that goal-directed modulation during maintenance was not merely a consequence of selective encoding. We further found that goal-directed modulation involves two functionally distinct processes that unfold dynamically over time, with the latter beginning even before stimulus offset and continuing throughout the entire maintenance phase. Finally, task decoding accuracy was consistently higher for successful than unsuccessful trials during maintenance.

Neural circuit models are essential for integrating observations of the nervous system into a consistent whole. Public sharing of well-documented codes for such models facilitates further development. Nevertheless, scientific practice in computational neuroscience suffers from replication problems and little re-use of circuit models. One exception is a data-driven model of early sensory cortex by Potjans and Diesmann that has advanced computational neuroscience as a building block for more complex models. As a widely accepted benchmark for correctness and performance, the model has driven the development of CPU-based, GPU-based, and neuromorphic simulators. On the 10th anniversary of the publication of this model, experts convened at the Käte Hamburger Kolleg Cultures of Research at RWTH Aachen University to reflect on the reasons for the model's success, its effect on computational neuroscience and technology development, and the perspectives this offers for the future of computational neuroscience. This report summarizes the observations by the workshop participants.