%0 Journal Article
%T Motion Extrapolation in the Central Fovea
%A Zhuanghua Shi
%A Romi Nijhawan
%J PLOS ONE
%D 2012
%I Public Library of Science (PLoS)
%R 10.1371/journal.pone.0033651
%X Neural transmission latency would introduce a spatial lag when an object moves across the visual field, if the latency was not compensated. A visual predictive mechanism has been proposed, which overcomes such spatial lag by extrapolating the position of the moving object forward. However, a forward position shift is often absent if the object abruptly stops moving (motion-termination). A recent ¡°correction-for-extrapolation¡± hypothesis suggests that the absence of forward shifts is caused by sensory signals representing ¡®failed¡¯ predictions. Thus far, this hypothesis has been tested only for extra-foveal retinal locations. We tested this hypothesis using two foveal scotomas: scotoma to dim light and scotoma to blue light. We found that the perceived position of a dim dot is extrapolated into the fovea during motion-termination. Next, we compared the perceived position shifts of a blue versus a green moving dot. As predicted the extrapolation at motion-termination was only found with the blue moving dot. The results provide new evidence for the correction-for-extrapolation hypothesis for the region with highest spatial acuity, the fovea.
%U http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0033651