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Synapses are fundamental to the function of the central nervous system and are implicated in a number of brain disorders. Despite their pivotal role, a comprehensive imaging resource detailing the distribution of synapses in the human brain has been lacking until now. Here, we employ high-resolution PET neuroimaging in healthy humans (17F/16M) to create a 3D atlas of the synaptic marker Synaptic Vesicle glycoprotein 2A (SV2A). Calibration to absolute density values (pmol/ml) was achieved by leveraging postmortem human brain autoradiography data. The atlas unveils distinctive cortical and subcortical gradients of synapse density that reflect functional topography and hierarchical order from core sensory to higher-order integrative areas-a distribution that diverges from SV2A mRNA patterns. Furthermore, we found a positive association between IQ and SV2A density in several higher-order cortical areas. This new resource will help advance our understanding of brain physiology and the pathogenesis of brain disorders, serving as a pivotal tool for future neuroscience research. [ABSTRACT FROM AUTHOR]

Neural systems have evolved to process sensory stimuli in a way that allows for efficient and adaptive behavior in a complex environment. Recent technological advances enable us to investigate sensory processing in animal models by simultaneously recording the activity of large populations of neurons with singlecell resolution, yielding high-dimensional datasets. In this review, we discuss concepts and approaches for assessing the population-level representation of sensory stimuli in the form of a representational map. In such a map, not only are the identities of stimuli distinctly represented, but their relational similarity is also mapped onto the space of neuronal activity. We highlight example studies in which the structure of representational maps in the brain are estimated from recordings in humans as well as animals and compare their methodological approaches. Finally, we integrate these aspects and provide an outlook for how the concept of representational maps could be applied to various fields in basic and clinical neuroscience. [ABSTRACT FROM AUTHOR]

Catatonia is featured by complex symptoms combining motor, affective and behavioral phenomena as well as by its syndrome character with trans-diagnostic occurrence. It paradigmatically shows the limits of current forms of psychopathology like affective and cognitive approaches with respect to both clinical symptoms and brain mechanisms. We therefore suggest Spatiotemporal Psychopathology (STPP) which, as recently introduced, is here developed further following the latest findings in both clinical psychiatry and neuroscience. STPP is characterized by two core features: (i) an experience-based approach that accounts for symptoms primarily in terms of first-person experience of time-space as distinct from third-person observation of specific functions and related behavior; (ii) an integrated brain-mind approach where the brain's neural topography and dynamic, e.g., inner time and space, are shared by the mind's mental topography and dynamic, e.g., time-space experience, as their "common currency". We demonstrate how these two features can well account for both symptom complexity and trans-diagnostic nature of catatonia. In conclusion, catatonia can serve as paradigmatic example for the need to develop a more comprehensive psychopathological approach in psychiatry. This is provided by STPP that allows integrating subjective experience, clinical symptoms and the brain's neural activity in terms of their inner space-time, e.g., topography and dynamic. [ABSTRACT FROM AUTHOR]

Phase change cooling garments (PCCGs) utilize phase change materials to store and release thermal energy, which can be used to reduce thermal sensation in hot environments. This study aims to investigate the effects of PCCGs on thermal comfort and electroencephalography (EEG) signals for laborers in hot conditions. Experiments were conducted in a climate chamber at 33 °C with 50 % relative humidity, with subjects having a metabolic rate of 2.7 met. EEG signals from 20 participants were recorded using a 32-channel EEG system after completing laboring task wearing the PCCGs or normal garment (NG), and the mean power of EEG and topological features of the brain network were analyzed. The results indicate that the use of PCCGs significantly reduce the mean power of the EEG signals, with notable changes in the θ, α, and β-bands. Additionally, wearing PCCGs alters the topological structure of the brain network, and the inter-regional information exchange was enhanced, as evidenced by the increased clustering coefficient, global efficiency, local efficiency, and decreased characteristic path length of the brain network. In this study, the effects of PCCGs on thermal comfort, EEG activity and brain network of laborers in hot environment were explored, which provides a possible indicator for assessing the improvement of thermal comfort by PCCGs. • Subjects' total brain power was significantly decreased after using PCCGs. • With PCCGs, the average power of θ,α, β band was significantly decreased in the EEG signals. • Number of edges in the α and β-bands was significantly increased after wearing PCCGs. • Using PCCGs increased clustering coefficients anddecreased characteristic path lengths in the α and β-bands. [ABSTRACT FROM AUTHOR]

Of the three largest outputs of the cerebral cortex, two have been extensively studied and mapped. Topographic maps of cortico-thalamic and cortico-striatal functional connectivity in humans are well established. However, for the third largest cerebral output, to the pontine nuclei, which connect the cerebrum to the cerebellum, the existence of such an organized connectivity pattern in humans is unknown. Here, using high-resolution functional MRI and a large sample size, we found a topographically organized pattern of functional connectivity between the human cerebral cortex and pons. Our results indicate a rostral-caudal topography; rostral (frontal) cerebral cortex shows connectivity to the rostral pons, and the more caudal cortical areas (i.e. the sensorimotor cortices) show functional connectivity more caudally in the pons, with the occipital lobe connectivity being most caudal. While prefrontal, sensorimotor and occipital cortices have a connectivity to the medial pontine nuclei, posterior parietal cortex and temporal lobe correlate with lateral pontine nuclei. Topography is sufficiently detailed to identify distinct connectivity for leg, trunk, hand and face areas of the motor cortex. These findings reveal the existence of a topographic organization in human cortico-pontine connectivity and provide the topographic map for future studies of cortico-ponto-cerebellum pathway in a variety of disorders., (Published by Oxford University Press on behalf of the Guarantors of Brain 2022. This work is written by (a) US Government employee(s) and is in the public domain in the US.)