Neuroscience
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Impaired finger motor function in post-stroke hemiplegia is a debilitating condition with no evidence-based or accessible treatments. Here, we evaluated the neurophysiological effectiveness of direct brain control of robotic exoskeleton that provides movement support contingent with brain activity. To elucidate the mechanisms underlying the neurofeedback intervention, we assessed resting-state functional connectivity with functional magnetic resonance imaging (rsfcMRI) between the ipsilesional sensory and motor cortices before and after a single 1-h intervention. ⋯ Although the neurofeedback intervention delivered fewer total sensorimotor stimulations compared to the sham-control, rsfcMRI in the ipsilesional sensorimotor cortices was increased during the neurofeedback intervention compared to the sham-control. Higher coactivation of the sensory and motor cortices during neurofeedback intervention enhanced rsfcMRI in the ipsilesional sensorimotor cortices. This study showed neurophysiological evidence that EEG-contingent neurofeedback is a promising strategy to induce intrinsic ipsilesional sensorimotor reorganization, supporting the importance of integrating closed-loop sensorimotor processing at a neurophysiological level.
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Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease affecting the corticospinal tract and leading to motor neuron death. According to a recent study, magnetic resonance imaging-visible changes suggestive of neurodegeneration seem absent in the motor cortex of G93A-SOD1 ALS mice. However, it has not yet been ascertained whether the cortical neural activity is intact, or alterations are present, perhaps even from an early stage. ⋯ The extracellular Na+, Ca2+, K+ and Cl- concentrations were elevated, pointing to perturbations in the culture micro-environment. Our findings highlight remarkable early changes in ALS cortical neuron activity and physiology. These changes suggest that the causative factors of hyperexcitability and associated toxicity could become established much earlier than the appearance of disease symptoms, with implications for the discovery of new hypothetical therapeutic targets.
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Emotional Stability Interacts with Cortisol Levels before fMRI on Brain Processing of Fearful Faces.
Functional-Magnetic-Imaging (fMRI) is widely adopted to investigate neurophysiological correlates of emotion processing (EP). However, studies have reported that scanning procedures in neuroimaging protocols may increase or cause anxiety and psychological distress related with the scanning, thus inducing peripheral cortisol release. These phenomena may in turn impact on brain EP. ⋯ In the context of lower ES, the opposite Δc-brain activity relationship was found. Our results suggest that the stressful potential of fMRI interacts with personality traits in modulating brain activity during EP. These findings should be taken into account when interpreting neuroimaging studies especially exploring brain physiology during EP.
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Sexually explicit material (SEM) is increasingly used in western societies. One reason for this high usage might be the rewarding property of SEM demonstrated in many brain imaging studies showing an activation of the reward system during the presentation of SEM. It is not yet well understood why women use SEM to a remarkably lesser extent than men. ⋯ There were some sex differences in hemodynamic responses to SEM during the presentation phase, but not during the expectation phase to SEM cues in any of the regions of interest. The influence of the investigated person characteristics was only small if existent. The results suggest that sex specific cue processing cannot explain sex differences in the use of SEM.
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Alzheimer's disease (AD) in the elderly is frequently accompanied by chronic cerebral hypoperfusion (CCH), which impairs the clearance of amyloid beta (Aβ) due to the dysfunction of the blood-brain barrier (BBB) and accelerates the AD pathology. Since the coagulation and complement cascades are associated with BBB dysfunction and AD pathology, we investigated the expression changes of coagulation (fibrinogen alpha chain-FGA, coagulation factor XIII A chain-Factor XIIIα) and complement (plasma protease C1 inhibitor-C1-INH, Complement component 3-C3) factors in the brain of novel AD model (APP23) mice with CCH at 12 months of age. Immunohistochemical and immunofluorescent analysis showed that the expressions of FGA, Factor XIIIα, C1-INH and C3 were significantly increased in cerebral neocortex, hippocampus, and thalamus of APP23 + CCH group (n = 12) as compared with wild type (WT, n = 10) and APP23 (n = 10) groups (⁎P < .05 and ⁎⁎P < .01 vs WT; #P < .05 and ##P < .01 vs APP23), especially near and inside of neurovascular unit. The present study suggests that CCH activated both the coagulation and complement cascades in a novel AD model mice brain accompanied by the acceleration of AD pathology.