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Park, A. S.

Publications and source records attributed to Park, A. S..

2 recordsLinked to original sources
bioRxiv2022

Efficacy of Non-invasive Brain Stimulation on Vision: A Systematic Review and Meta-analysis

ObjectiveMultiple studies have explored the use of non-invasive brain stimulation (NIBS) to enhance visual function. These studies vary in sample size, outcome measures, and NIBS methodology. We conducted a systematic review and meta-analyses to assess the effects of NIBS on visual functions in human participants with normal vision. MethodsWe followed the PRISMA guidelines, and a review protocol was registered with PROSPERO before study commencement (CRD42021255882). We searched Embase, Medline, PsychInfo, PubMed, OpenGrey and Web of Science using relevant keywords. The search covered the period from 1st January 2000 until 1st September 2021. Comprehensive meta-analysis (CMA) software was used for quantitative analysis. ResultsForty-nine studies were included, of which 19 were included in a meta-analysis (38.8%). Meta-analysis indicated acute (Hedgess g=0.232, 95% CI: 0.023-0.442, p=0.029) and aftereffects (0.590, 95% CI: 0.182-0.998, p=0.005) of transcranial electrical stimulation (tES, including three different stimulation protocols) on contrast sensitivity. Visual evoked potential (VEP) amplitudes were significantly enhanced immediately after tES (0.383, 95% CI: 0.110-0.665, p=0.006). Both tES (0.563, 95% CI: 0.230 to 0.896, p=0.001)] and anodal-transcranial direct current stimulation (a-tDCS) alone (0.655, 95% CI: 0.273 to 1.038, p=0.001) reduced crowding in peripheral vision. The effects of NIBS on visual acuity, motion perception and reaction time were not statistically significant. ConclusionsThere are significant effects of visual cortex NIBS on contrast sensitivity, VEP amplitude, an index of cortical excitability, and crowding among normally sighted individuals. Future studies with robust experimental designs are needed to substantiate these findings in populations with vision loss. PROSPERO registration numberCRD42021255882 HighlightsO_LIWe conducted a meta-analysis and a systematic review on the efficacy of non-invasive brain stimulation for improving on visual function C_LIO_LIVisual cortex non-invasive brain stimulation can enhance contrast sensitivity, reduce crowding in peripheral vision and enhance visually evoked potential amplitude among normally sighted individuals. C_LI

neuroscience↗
bioRxiv2022

Activation of the fear-responsive anterior hypothalamic area promotes avoidance and triggers compulsive grooming behavior in mice

The anterior hypothalamic area (AHA) is a key brain region for orchestrating defensive behaviors. Here, we first examined AHA activity patterns during fear conditioning using in vivo functional imaging. We observed that neuronal activity in the AHA increases during both foot shock delivery and foot-shock associated auditory cues. Moreover, we used a combination of optogenetics and behavioral assays to determine the functional connectivity between the ventromedial hypothalamus (VMH) and the AHA. We found that photoactivation of the VMH[->]AHA pathway is aversive and triggers compulsive grooming behavior. Furthermore, we observed spatial and temporal changes of grooming behavior during the periods following VMH[->]AHA photoactivation. Interestingly, whole brain metabolic mapping using positron emission tomography (PET) combined with optogenetic activation of the VMH[->]AHA pathway in anesthetized mice revealed the amygdala as a downstream area activated by the stimulation of this pathway. Together, our findings show that the AHA responds to threat and that such increases in activity are sufficient to trigger compulsive grooming behavior. Thus, our results may help to understand some neuropsychiatric disorders characterized by repetitive and compulsive behaviors.

neuroscience↗