Neuroscience
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Absence Epilepsy (AE) is associated with recurrent losses of awareness and synchronous bilateral spike-wave discharges (SWDs). While seizures do not generally continue into adulthood, cognitive and behavioral comorbidities persist. One preclinical model used to investigate AE is the Genetic Absence Epilepsy Rats from Strasbourg (GAERS) which consistently have bilateral SWDs and similar behavioral profiles. ⋯ Deficits in VD and RL were not associated with differences in correct or incorrect response latency, or reward collection latency, suggesting impairments are not due to alterations in locomotor activity or motivation. Together, these data suggest that GAERS have impaired behavioral flexibility and identify some sex-dependent differences. Thus, GAERS may be suitable for assessing the potential benefit of antiepileptic drugs on comorbid behavioral and cognitive deficits.
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Calcium acts as a second messenger that mediates physiologic functions, such as metabolism, cell proliferation, and apoptosis. Hippocalcin is a neuronal calcium sensor protein that regulates intracellular calcium concentration. Moreover, it prevents neuronal cell death from oxidative stress. ⋯ Furthermore, caspase-3 expression in hippocalcin siRNA transfection conditions is higher than caspase-3 expression in un-transfection conditions. Quercetin treatment attenuated the increase of caspase-3. Taken together, these results suggest that quercetin exerts a preventative effect through attenuation of intracellular calcium overload and restoration of down-regulated hippocalcin expression during ischemic injury.
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The objective of this study was to examine the interactive effects of exercise and low-level inhibition of GABAA receptors on the recovery of motor function and BDNF expression in the primary motor cortex (M1) of a stroke rat model. Male Sprague-Dawley rats were divided into five groups: sham (SHAM), control (CON), exercise (EX), bicuculline (BIC), and bicuculline plus exercise (BICEX) groups. All rats, except those in the SHAM group, underwent middle cerebral artery occlusion (MCAO) surgery to induce an ischemic stroke. ⋯ Furthermore, BDNF protein level in the ipsilateral M1 was significantly higher in the BICEX group than in other groups. This study indicated that exercise combined with low-level inhibition of GABAA receptors after stroke could facilitate the recovery of motor function accompanied by BDNF upregulation in the ipsilateral M1. Therefore, this study provides a novel insight of pharmacological neuromodulation into stroke rehabilitation.
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Previous studies have identified the ventral and dorsal brain regions that respectively support semantic and non-semantic phonological access. Nevertheless, the specific role of the left occipitotemporal cortex (lOTC) in the two pathways of phonological access is ambiguous. To address that question, the present study compared word reading in Chinese (presumably relying on the semantic pathway) with that in English (presumably relying on the non-semantic pathway). ⋯ Specifically, the anterior lOTC showed greater activation for Chinese than for English, whereas the posterior lOTC showed greater activation for English than for Chinese. More importantly, both psychophysiological interaction analysis and resting-state functional connectivity analysis showed that the anterior lOTC was functionally connected to the ventral brain regions (e.g., left anterior fusiform gyrus, anterior temporal lobe, and ventral inferior frontal gyrus), whereas the posterior lOTC was functionally connected to the dorsal brain regions (e.g., left posterior superior temporal gyrus, supramarginal gyrus, and dorsal inferior frontal gyrus). These results suggest that the anterior and posterior lOTC are involved in semantic and non-semantic phonological access, respectively.
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The current project investigated the dynamics of postural movements and muscle activity during balancing with feet-together and feet-apart positions on different support surfaces (firm surface (FS), modified- and conventional balance boards). We hypothesized that movement complexity and muscle activation would increase with increased balance-task difficulty, and that differences in the composition and control of postural movements between bipedal wide- and narrow-based balancing would be observed in all surface conditions. We applied a principal component analysis (PCA) to decompose postural movement trajectories of 26 active-young adults into sets of movement components (principal movements; PMs). ⋯ Standing on the stable surface illustrated opposite control behaviors compared to balancing on both multiaxial-unstable surfaces. In summary, on stable surface, changing the feet position affected inter-segment coordination. On unstable surfaces, the postural control system appeared to maintain inter-segment coordination characteristics, while the adaptation was confined to the sensorimotor integration processes.