Neuroscience
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Randomized Controlled Trial
Upper Limb Motor Training Based on Task-Oriented Exercises Induces Functional Brain Reorganization in Patients with Multiple Sclerosis.
The aim of this work was to investigate changes in motor performance and in the brain activation pattern during finger movements, following upper limb motor training in multiple sclerosis. Thirty people with multiple sclerosis with mild upper limb sensorimotor deficits were randomly allocated to one of two groups: the experimental group (n = 15) received an upper limb treatment based on voluntary task-oriented movements; the control group (n = 15) underwent passive mobilization of shoulder, elbow, wrist and fingers. All participants completed three treatment sessions per week for eight weeks. ⋯ However, only the experimental group showed increased lateralization towards more normal brain activation following treatment, with activation clusters mainly located in the left brain hemisphere and right cerebellum. In conclusion, both active and passive interventions were effective in improving motor performance. However, only the treatment based on voluntary task-oriented movements could induce changes in brain activity that may have reflected skill acquisition by the right hand, reducing the activation of compensatory areas and decreasing brain resource demand.
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Prescription opioid abuse is a serious public health issue. Recently, we showed that female and male Sprague-Dawley rats acquire conditioned place preference (CPP) to the mu opioid receptor agonist oxycodone. Anatomical analysis of the hippocampus from these rats unveiled sex differences in the opioid system in a way that would support excitation and opiate associative learning processes especially in females. ⋯ Oxycodone CPP females have: a) increases in ARC (activity regulated cytoskeletal-associated protein)-immunoreactivity (ir) in CA3 pyramidal cells; b) decreases in Npy (neuropeptide Y) gene expression in the medial hippocampus but higher numbers of NPY-containing hilar interneurons compared to males; c) increases in Crhr2 (corticotropin releasing factor receptor 2) expression in CA2/3; d) increases in Akt1 (AKT serine/threonine kinase 1) expression in medial hippocampus; and e) decreases in phosphorylated MAPK (mitogen activated protein kinase)-ir in CA1 and dentate gyrus. Oxycodone CPP males have: a) increases in Bdnf (brain derived-neurotrophic factor) expression, which is known to be produced in granule cells, relative to females; b) elevated Mapk1 expression and pMAPK-ir in the dentate hilus which harbors newly generated granule cells; and c) increases in CRHR1-ir in CA3 pyramidal cell soma. These sex-specific changes in plasticity, stress and kinase markers in hippocampal circuitry parallel previously observed sex differences in the opioid system after oxycodone CPP.
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Comparative Study
Comparison of Actions between L-DOPA and Different Dopamine Agonists in Striatal DA-Depleted Microcircuits In Vitro: Pre-Clinical Insights.
Parkinson's disease (PD) is a neurodegenerative illness presenting motor and non-motor symptoms due to the loss of dopaminergic terminals in basal ganglia, most importantly, the striatum. L-DOPA relieves many motor signs. Unfortunately, in the long term, L-DOPA use causes motor disabilities by itself and does not act in comorbid conditions such as depression. ⋯ All DA-agonists tend to maintain ensemble alternation seen in control circuits after CtxS. However, quantitative analyses suggest differences in their actions: in general, DA-agonists only approximate L-DOPA actions. Nonetheless no treatment, including L-DOPA, completely restores microcircuit dynamics to control conditions.
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Previous studies have found that native Chinese speakers recruit the bilateral fusiform gyrus to read English words, in the same manner as they read Chinese words (i.e., the assimilation process). In this study, we quantified the neural pattern similarity between native (L1) and second languages (L2) by using representational similarity analysis (RSA), and examined the modulatory effects of L2 proficiency on cross-language neural pattern similarity (PS) in the bilateral fusiform cortex. Results showed that, for Chinese-English bilinguals, higher reading proficiency in L2 was associated with greater cross-language PS in the left fusiform gyrus, but with lower PS in the right fusiform gyrus. These results suggest that, as L2 proficiency increases, the assimilation process is enhanced in the region for word reading (left fusiform gyrus), but reduced in the region for nonlinguistic processing (right fusiform gyrus).
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Memories are acquired and stored in two forms, short-term memory (STM) and long-term memory (LTM). For the consolidation of LTM, de novo protein synthesis is required, which are also known as plasticity related proteins. Long-term potentiation is a form of synaptic plasticity and it is considered as a cellular model of learning and memory. ⋯ Despite being studied for LTM formation for many years, no studies so far have investigated the role of PKM-ζ in Behavioral tagging model. Hence, by using these two different memories based tasks (i.e., Inhibitory avoidance and Novel object recognition tasks), we observed how PKM-ζ activated by exposing a novel arena after a weak training and led to the consolidation of memory. These findings thus show how the process of behavioral tagging activates Long-term potentiation -specific PKM-ζ for the formation of LTM.