Neuroscience
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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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Subcortical auditory nuclei contribute to pitch perception, but how subcortical sound encoding is related to pitch processing for music perception remains unclear. Conventionally, enhanced subcortical sound encoding is considered underlying superior pitch discrimination. However, associations between superior auditory perception and the context-dependent plasticity of subcortical sound encoding are also documented. ⋯ When the spectral strength was controlled by partial correlations, the negative ITPL-behavioral correlations were maintained. Furthermore, the FFR ITPL, the plasticity indices, and the FFR spectral strength were more correlated with pitch than with rhythm discrimination performances. These findings suggest that the context-dependent plasticity and the strength of subcortical encoding of musical sounds are independently and perhaps specifically associated with pitch perception for music melodies.
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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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The global fractional anisotropy (gFA) is a structural marker of white matter myelination and integrity. Previous studies already evidenced that aging-related reduced integrity of specific white matter tracts is associated with decreased functional connectivity in several hubs. However, the correlations between gFA and functional brain connectivity remain unknown. ⋯ Higher values of gFA were associated with increased brain regional activity, including areas of the default mode network. There was a higher degree of correlation between some regions, particularly those that conform to the limbic system. Our study demonstrates that gFA influences regional neural activity and brain networking on resting, particularly the limbic system.
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Understanding the different mechanisms associated with different anesthetic targeted receptors is critical towards identifying accurate long-term outcome measures as a result of early-life anesthetic exposure. We examined changes in GABAA receptor mediated neurotransmission by a predominately GABAA receptor targeted anesthetic, sevoflurane or a predominately NMDA receptor targeted anesthetic, ketamine. Postnatal day 7 male mice were exposed to sevoflurane or ketamine and examined as adults for changes in inhibitory neurotransmission and its associated change in induced seizure activity. ⋯ While sevoflurane treated mice showed significantly higher induced seizure intensities and shorter latency periods to reach seizure intensity stage 5 (Racine score) compared with no sevoflurane treated mice, this phenomenon was not observed in the ketamine vs. saline treated groups. Early-life sevoflurane, but not ketamine, exposure reduced GABAergic inhibition and enhanced seizure activity later in life. The results indicate that early-life exposure to different anesthetics lead to distinct long-term effects and their unique pathways require mechanistic studies to understand induced long-lasting changes in the brain.