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bioRxiv · 10.1101/448498

Visual plasticity and exercise revisited: no evidence for a \"cycling lane\"

Abstract

Experiments using enriched environments have shown that physical exercise modulates visual plasticity in rodents. A recent study (Lunghi & Sale, 2015, doi: 10.1016/j.cub.2015.10.026) investigated whether exercise also affects visual plasticity in adult humans. The plastic effect they measured was the shift in ocular dominance caused by 2 hours of monocular deprivation (e.g. by an eye patch). They used a binocular rivalry task to measure this shift. They found that the magnitude of the shift was increased by exercise during the deprivation period. This effect of exercise was later disputed by a study that used a different behavioural task (Zhou et al., 2017, doi: 10.1155/2017/4780876). Our goal was to determine whether the difference in task was responsible for that studys failure to find an exercise effect. We set out to replicate Lunghi & Sale (2015). We measured ocular dominance with a rivalry task before and after 2 hours of deprivation. We measured data from two conditions in 30 subjects. On two separate days they either performed exercise or rested during the deprivation period. Contrary to the previous study, we find no significant effect of exercise. We hypothesise that exercise may affect rivalry dynamics in a way that interacts with the measurement of the deprivation effect.

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Finn, A. E., Baldwin, A. S., Reynaud, A., Hess, R. F.. 2018-10-24. Visual plasticity and exercise revisited: no evidence for a \"cycling lane\". https://doi.org/10.1101/448498

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