Neuroscience
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Visual-related cortex plays an important role in the process of movement. It is of great importance to clarify whether traumatic spinal cord injury (SCI), which is a typical disease that results in sensorimotor dysfunction, leads to the alteration of visual-related brain structure and function area. To address this issue, multimodality MRI was applied on eleven patients with acute incomplete cervical cord injury (ICCI) and eleven healthy controls (HCs) to explore possible structural and functional changes of the brain. ⋯ Moreover, ICCI patients exhibited decreased intra-network functional connectivity (FC) in the medial vision network (mVN). The mean fALFF value was correlated with clinical motor scores of the left extremities and the total motor scores. Our findings proved that ICCI can not only cause structural changes in visual-related brain regions, but also result in visual-related brain functional alterations, revealing the possible mechanism of the effects of visual feedback training in motor function rehabilitation of SCI patients.
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Diglossia in the Arabic language refers to the socio-linguistic situation in which Spoken Arabic (SA), which is the first to be acquired, is used for everyday communications, while Literary Arabic (LA), acquired at school for reading and writing, is also used for formal functions. Although some authors consider SA and LA as a first and second language, the question of how these are managed in the brain has not yet been understood. Using functional magnetic resonance brain imaging (fMRI) analysis, this study aimed at exploring the neural basis of diglossia during picture naming in two contexts. ⋯ Behavioral analysis showed that naming in SA was slightly easier than LA and considerably easier than Hebrew. fMRI analysis showed no difference between SA and LA. Hebrew compared to SA revealed activation differences explainable in terms of engagement of language control modules and second- to first-language effects. These findings, discussed in the light of previous findings in bilingual literature, support the view that dominance in diglossia is modality-dependent.
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Accumulating evidence has accrued demonstrating that inflammatory processes in the central nervous system (CNS) are associated with various neurological disorders including depression. However, whether inflammation-mediated neuronal damage is involved in depression-like behaviors induced by chronic stress and, in particular, whether suppression of inflammation could then serve as a potential strategy in depression therapy remains largely unknown. The present study aimed to investigate the neuronal mechanisms and signaling pathways through which inflammation results in neuronal deterioration in a rat model of depression and thus identify agents with potential roles as antidepressant treatments. ⋯ In contrast, chronic administration of either IL-1β or nuclear factor κB (NF-κB) antagonists significantly ameliorated this dysregulation of neuronal structure and biochemical parameters such as SSH1 and phospho-cofilin within the mPFC, as well as the display of depression-like behaviors induced by CUMS exposure. More importantly, pretreatment with curcumin (40 mg/kg, i.p., 5 weeks), produced antidepressant-like actions and repressed the inflammatory responses and neuronal structural abnormalities. These findings reveal some of the molecular neuroinflammation pathways associated with depression and suggest new avenues of investigation for the development of potential antidepressant therapies in the treatment of inflammation-related neuronal deterioration in this disorder.
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Motor actions can be released much sooner than normal when the go-signal is of very high intensity (>100 dBa). Although statistical evidence from individual studies has been mixed, it has been assumed that sternocleidomastoid (SCM) muscle activity could be used to distinguish between two neural circuits involved in movement triggering. We summarized meta-analytically the available evidence for this hypothesis, comparing the difference in premotor reaction time (RT) of actions where SCM activity was elicited (SCM+ trials) by loud acoustic stimuli against trials in which it was absent (SCM- trials). ⋯ Our mini meta-analysis showed that premotor RTs are faster in SCM+ than in SCM- trials, but the effect can be confounded by the variability of the foreperiods employed. We present experimental data showing that foreperiod predictability can induce differences in RT that would be of similar size to those attributed to the activation of different neurophysiological pathways to trigger prepared actions. We discuss plausible physiological mechanisms that would explain differences in premotor RTs between SCM+ and SCM- trials.
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Alterations in excitatory and inhibitory neurotransmitters (glutamate and GABA, respectively) have been found in various neuropsychiatric disorders, but have not been examined in individuals with prodigious cognitive abilities. Understanding exceptional brain processing is critical for developing biomedical interventions for cognitive and neurodevelopmental atypicalities. ⋯ We found substantially lower frontal glutamate/GABA compared to non-prodigy controls, but not glutamate or GABA individually, measured with magnetic resonance spectroscopy. We suggest that prefrontal glutamate/GABA is a potential marker of extraordinary cognitive skills.