NeuroImage
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The abilities to empathize and to systemize, two fundamental dimensions of cognitive style, are characterized by apparent individual differences. These abilities are typically measured using an empathizing quotient (EQ) and a systemizing quotient (SQ) questionnaire, respectively. The purpose of this study was to reveal any correlations between EQ and SQ scores and regional gray matter volumes in healthy children by applying voxel-based morphometry to magnetic resonance images. ⋯ The EQ-C scores showed significant positive correlations with the regional gray matter volumes of the left fronto-opercular and superior temporal cortices, including the precentral gyrus, the inferior frontal gyrus, the superior temporal gyrus, and the insula, which are functionally related to empathic processing. Additionally, SQ-C scores showed a significant negative correlation with the regional gray matter volume of the left posterior parietal cortex, which is functionally involved in selective attention processing. Our findings suggest that individual differences in cognitive style pertaining to empathizing or systemizing abilities could be explained by differences in the volume of brain structures that are functionally relevant to empathizing and systemizing.
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During the maintenance period of propofol-induced general anesthesia, specific changes in spontaneous EEG rhythms can be observed. These comprise increased delta and theta power and the emergence of alpha oscillations over frontal regions. In this study we use a meanfield model of the thalamo-cortical system to reproduce these changes and to elucidate the underlying mechanisms. ⋯ Specifically, while observed increases in delta and alpha power are reflections of amplified resonances in the respective frequency bands, increases in theta power are caused indirectly by spectral power leakage from delta and alpha bands. The model suggests that these changes are brought about through increased inhibition within local cortical interneuron circuits. These results are encouraging and motivate more extensive use of neural meanfield models in elucidating the physiological mechanisms underlying the effects of pharmacological agents on macroscopic brain dynamics.