Purchase this article with an account.
I-Fan Lin, Andrei Gorea; The spatial coordinate system for trans-saccadic information storage. Journal of Vision 2010;10(7):558. doi: 10.1167/10.7.558.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
While memory storage of objects identity and of their spatiotopic locations may sustain cross-saccadic stability of the world, retinotopic location storage may hamper it. Is it then true that saccades perturb more retinotopic than spatiotopic memory storage? We address this issue by assessing localization performances of the penultimate (N-1) saccade-target in a series of 3 to 6 saccades. One white letter-pair (target) and eight black letter-pairs (distracters) were displayed on a virtual 3° radius circle around a fixation dot for 100 ms within a 20°x20° gray rectangular frame. Subjects were instructed to saccade to the target. Once the eye landed at the target position, now displaying a fixation dot, a spatially permuted target-distracters arrangement was displayed anew around the fixation dot and triggered the next saccade. At the end of a trial, a color change of the fixation dot prompted subjects to report the location of the target in either retinotopic or spatiotopic coordinates. The retinotopic location was referred to the fixation dot. The spatiotopic location was referred to the gray frame. Identical conditions were run with the eyes maintaining fixation throughout the trial but with the gray frame moving so as to mimic its retinal displacement when the eyes moved. Spatiotopic location was better stored (by ∼0.33 d' units) and reported faster (by ∼140 ms) in the saccade compared to the maintained fixation condition. Instead, saccades degraded retinotopic location memory (by ∼0.29 d' units) and delayed response time (by ∼68 ms). The better and faster spatiotopic location storage and retrieval during eye-movements is compatible with the notion that spatiotopic representation takes over retinotopic representation during eye movements thereby contributing to the stability of the visual world as its projection jumps on our retina from saccade to saccade.
This PDF is available to Subscribers Only