Neuroscience
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There are many uncontrollable factors in the pathogenesis of cerebral venous sinus thrombosis (CVST). In order to further explore the pathophysiology and morphology of CVST, it is necessary to establish a highly compatible CVST animal model that can standardize the site and stage of venous thrombosis. The present study employed the insertion of a self-made thread embolism into the superior sagittal sinus (SSS) to establish a rat model of SSS occlusion that emulates CVST. ⋯ Removing SSS occlusion significantly improved cerebral circulation, reduced brain edema, and accelerated the receding of brain edema. This study established a new model of acute occlusion and recanalization of SSS in rats via a thread-embolism method, which standardized the ischemic site and stage of venous thrombosis. In addition, our study suggests that promoting collateral circulation may be a potential treatment for promoting brain protection.
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Turning elicits Freezing of Gait (FoG) episodes in people with Parkinson's disease (PD) and is thought to require higher cortical control compared to straight ahead gait. Functional near infrared spectroscopy (fNIRS) has been used to examine prefrontal cortex (PFC) activity while walking, but the relationship between PFC activity and turn performance remains unclear. The aim of this pilot study was to examine PFC activity during turning in PD and healthy controls, and to investigate the association between PFC activity and turning. ⋯ In addition, higher PFC is associated with worse FoG in PD + FoG (r = 0.57, p = .048) and with lower number of turns in PD - FoG (r = -0.70, p = .002). The increased PFC activity in PD and the association between higher PFC activity and poorer turning performance may be a sign of poor movement automaticity in PD. Although further investigations are required, these pilot findings may guide development of personalized treatments to improve motor automaticity in PD.
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The glare illusion enhances the perceived brightness of a central white area surrounded by a luminance gradient, without any actual change in light intensity. In this study, we measured the varied brightness and neurophysiological responses of electroencephalography (EEG) and pupil size with the several luminance contrast patterns of the glare illusion to address the question of whether the illusory brightness changes to the glare illusion process in the early visual cortex. We hypothesized that if the illusory brightness enhancement was created in the early stages of visual processing, the neural response would be similar to how it processes an actual change in light intensity. ⋯ We found the SSVEP amplitude was lower in the glare illusion than in the control condition, especially under high luminance contrast conditions. Furthermore, we found the probable mechanisms of the inhibited SSVEP amplitude to the high luminance contrast of glare illusion based on the greater pupil constriction, thereby decreasing the amount of light entering the pupil. Thus, the brightness enhancement in the glare illusion is already represented at the primary stage of visual processing linked to the larger pupil constriction.
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L2 processing is shaped by L1 experience; however, it is not completely understood whether L1 reading experience also influences how the brain learns L2 under different learning conditions. In this study, we compare brain mechanisms of Spanish word learning in Chinese and English speakers using two learning conditions: speech-based learning and handwriting-based learning. The behavioral data suggest an advantage for learning that uses handwriting over speech-based learning across all participants. ⋯ Thus, the handwriting-based learning engaged visuo-orthographic regions to a greater degree in highly skilled Chinese speakers. In summary, the current findings suggest that handwriting facilitates lexical learning by enhancing orthographic involvement in Chinese speakers, while the handwriting condition enhanced phonological involvement in English speakers. This difference between Chinese and English speakers might be due to different L1 learning experience.
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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.