Neuroscience
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Previous studies have established the importance of the fronto-parietal brain network in the information processing of reasoning. At the level of cortical source analysis, this eletroencepalogram (EEG) study investigates the functional reorganization of the theta-band (4-8Hz) neurocognitive network of mathematically gifted adolescents during deductive reasoning. ⋯ Further correlation analyses have shown that the enhanced workspace configuration with respect to the global topological metrics of the theta network in math-gifted subjects is correlated with the intensive frontal midline theta (fm theta) response that is related to strong neural effort for cognitive events. These results suggest that by investing more cognitive resources math-gifted adolescents temporally mobilize an enhanced task-related global neuronal workspace, which is manifested as a highly integrated fronto-parietal information processing network during the reasoning process.
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Tastes and odors influence the perception of a meal. Especially food aromas can act as potent signals to modulate our eating behavior with strong dependency on the reward produced by food. In this investigation we aimed to study the electrophysiological response to food- and non-food-related odors in healthy volunteers. Analyses revealed specific scalp potential maps for the two conditions; in particular the source of the map in the "food" condition seemed to be associated with the processing of rewards; the specific map in the "non-food" condition reflects odor characteristics excluding the reward.
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We tested predictions of a hierarchical scheme on the control of natural movements with referent body configurations. Subjects occupied an initial hand position against a bias force generated by a HapticMaster robot. A smooth force perturbation was applied to the hand consisting of an increase in the bias force, keeping it at a new level for 5s, and decreasing it back to the bias value. ⋯ We interpret unintentional movements as consequences of back-coupling between the actual and referent configurations at the task level. The results suggested that both intentional and unintentional movements resulted from shifts of the body referent configuration produced intentionally or as a result of the hypothesized back-coupling. Inter-trial variance signature reflects similar task-specific stability properties of the system following both types of movements, intentional and unintentional.
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Hemifacial spasm (HFS) is a peripheral nerve disorder which impacts the living quality of patients both psychologically and physically. Whether HFS has structural changes under these specific stressors including psychological and physiological conditions in the CNS remains largely unknown. In the current study, voxel-based morphometry (VBM) was used to evaluate changes in gray matter (GM) by using T1-weighted imaging in 25 HFS patients and 25 demographically similar healthy volunteers. ⋯ Additionally, the GM volume changes in the amygdala did not exhibit any significant between-group differences with HAMA and HAMD scores as covariates. Our results suggested that HFS probably led to GM volume abnormalities of the CNS. We indicated that the GM volume changes of the amygdala may be highly related to emotional factors.
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Two major neurotrophic factors, nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF) are involved in a number of physiological processes associated with neuronal growth, survival and plasticity. There are an increasing number of papers demonstrating their ability to serve as neuroprotective molecules under various pathological conditions. At the same time, it remains unclear whether both NGF and BDNF have similar roles under pathological conditions and their effects on the electrophysiological properties of neurons after acute pathogen exposure. ⋯ One week after virus injection acute brain slices were incubated with beta-amyloid (25-35) for 1h and afterward in vitro LTP induction was performed in medial perforant path-DG synapses. We demonstrate that chronic elevation of NGF but not BDNF concentration protects LTP induction from beta-amyloid action. Further inhibitory analysis suggests that the effect of NGF is mediated by PI3K-signaling cascade.