Neuroscience
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Neuropathic pain (NP) is characterized by the presence of spontaneous pain, allodynia and hyperalgesia. Repetitive transcranial magnetic stimulation (rTMS) is one of neuromodulatory techniques that induces satisfactory NP relief, including that from refractory pain patients. The objective of this study was to evaluate rTMS treatment over long term memory (LTM) and hippocampal BDNF and IL-10 levels in rats submitted to a NP model. ⋯ Biochemical assays (BDNF and IL-10 levels) were performed in hippocampus tissue homogenates. rTMS treatment reversed the reduction of the discrimination index in the ORT and the hippocampal IL-10 levels in NP rats. This result shows that rTMS reverses the impairment LTM and the increase in the hippocampal IL-10 levels, both induced by NP. Moreover, it appears to be a safe non-pharmacological therapeutic tool since it did not alter LTM and neurochemical parameters in naive animals.
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Establishing consistent relationships between neural activity and behavior is a challenge in human cognitive neuroscience research. We addressed this issue using variable time constraints in an oddball frequency-sweep design for visual discrimination of complex images (face exemplars). Sixteen participants viewed sequences of ascending presentation durations, from 25 to 333 ms (40-3 Hz stimulation rate) while their electroencephalogram (EEG) was recorded. ⋯ The behavioral face individuation response also emerged at 50 ms presentation time, and behavioral accuracy correlated with individual participants' neural response amplitude in a weighted middle stimulus duration range (50-125 ms). Moreover, the latency of the neural response peaking between 180 and 200 ms correlated strongly with individuals' behavioral accuracy in this middle duration range, as measured independently. These observations point to the minimal (50 ms) and optimal (170 ms) stimulus durations for human face individuation and provide novel evidence that inter-individual differences in the magnitude and latency of early, high-level neural responses are predictive of behavioral differences in performance at this function.
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Psychological resilience is always portrayed as the ability to rebound from adversity, which is essential for human mental health. Whereas thought control ability (TCA) is a reliable indicator of perceptual cognitive control and has a predictive effect on psychopathology. Whether and how resilience correlates with thought control are still unclear. ⋯ Results reveled a significant positive correlation between resilience and the functional connectivity of temporal cortex-insula, suggesting that individuals with high resilient ability exhibit flexible interaction between these two regions to facilitate emotional information processing. More importantly, a significant positive correlation between TCA and resilience was observed, and the functional connectivity of temporal cortex-insula has a significant mediation effect on the association between TCA and psychological resilience, revealing that individuals with high TCA show high levels of resilience ability through robust cognitive control on unwanted thoughts. In short, these results extended previous findings by shedding novel insights into the close relationship between resilience and TCA and the underlying neural mechanism.
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Studying the nonlinear synchronization of electroencephalogram (EEG) in type 2 diabetic mellitus (T2DM) to find the EEG characteristics related to cognitive impairment is beneficial to the early prevention and diagnosis of mild cognitive impairment. Correlation between probabilities of recurrence (CPR) is a nonlinear phase synchronization method based on recurrence and recurrence probability, which had shown its superiority in detecting epilepsy. In this study, CPR method was used for the first time to analyze the synchronization of eye-closed resting EEG signals with T2DM. ⋯ The CPR values were significantly different in frontal, parietal and temporal regions in intra hemispheric between two groups. The CPR values of C3-F7, F4-C4 and FP2-T6 were significantly positively correlated with the MOCA values. This study showed that the synchronization values of EEG signals obtained by the CPR method were significantly different between aMCI and control group, and they were the EEG characteristics associated with cognitive impairment in T2DM.
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Lifelong auditory and visual sensory deprivation have been demonstrated to alter both perceptual acuity and the neural processing of remaining senses. Recently, it was demonstrated that individuals with anosmia, i.e. complete olfactory sensory deprivation, displayed enhanced multisensory integration performance. Whether this ability is due to a reorganization of olfactory processing regions to focus on cross-modal multisensory information or whether it is due to enhanced processing within multisensory integration regions is not known. ⋯ However, exploratory whole-brain analysis suggested higher activation related to multisensory integration within the posterior superior temporal sulcus, in close proximity to the multisensory region of interest, in individuals with congenital anosmia. No group differences were demonstrated in olfactory associated regions. Although results were outside our hypothesized regions, combined, they tentatively suggest that enhanced processing of audio-visual stimuli in individuals with congenital anosmia may be mediated by multisensory, and not primary sensory, cerebral regions.