Neuroscience
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Individuals with autism spectrum disorder (ASD) have been associated with sensorimotor difficulties, commonly presented by poor postural control. Postural control is necessary for all motor behaviors. However, findings concerning the effect of visual motion on postural control and the age progression of postural control in individuals with ASD are inconsistent. ⋯ However, adults with ASD appeared more responsive to forward-moving optic flow in the peripheral visual field compared with typically developed adults. The findings suggest that children and adults with ASD may not display maladaptive postural responses all the time. In addition, adults in the ASD group may have difficulties prioritizing visual information in the central visual field over visual information in the peripheral visual field when in unfamiliar environments, which may have implications in understanding their motor behaviors in new surroundings.
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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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Cerebral palsy is an irreversible movement disorder resulting from cerebral damage sustained during prenatal or neonatal brain development. As survival outcomes for preterm injury improve, there is increasing need to model ischemic injury at earlier neonatal time-points to better understand the subsequent pathological consequences. ⋯ These include a robust motor deficit sustained into adulthood and recapitulation of hallmark features of preterm human brain injury, including atrophy of subcortical white matter and periventricular fiber bundles. Compared to procedures involving carotid artery manipulation and periods of hypoxia, the ET-1 ischemia model represents a rapid and technically simplified model more amenable to larger cohorts and with the potential to direct the locus of ischemic damage to specific brain areas.
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Microglia, the brain resident immune cells, play prominent roles in immune surveillance, tissue repair and neural regeneration. Despite these pro-survival actions, the relevance of these cells in the progression of several neuropathologies has been established. In the context of manganese (Mn) overexposure, it has been proposed that microglial activation contributes to enhance the neurotoxicity. ⋯ Altogether these events point to lysosomes as players in the execution of RN. In summary, our results suggest that microglial cells could be direct targets of Mn2+ damage. In this scenario, Mn2+ triggers cell death involving RN pathways.
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Recently studies have aimed at developing transcutaneous spinal direct current stimulation (tsDCS) as a non-invasive technique to modulate spinal function in humans. Independent studies evaluating its after-effects on nociceptive or non-nociceptive somatosensory responses have reported comparable effects suggesting that tsDCS impairs axonal conduction of both the spino-thalamic and the medial lemniscus tracts. ⋯ Low-thoracic tsDCS selectively and significantly affected the LEP-N2 wave elicited by nociceptive stimulation of the lower limbs, without affecting the LEP-N2 wave elicited by nociceptive stimulation of the upper limbs, and without affecting the SEP-N2 wave elicited by vibrotactile stimulation of either limb. This selective and segmental effect indicates that the neuromodulatory after-effects of tsDCS cannot be explained by anodal blockade of axonal conduction and, instead, are most probably due to a segmental effect on the synaptic efficacy of the local processing and/or transmission of nociceptive inputs in the dorsal horn.