1. From: Voluntary control of long-range motion integration via selective attention to context
Journal of Vision. 2008;8(11):18. doi: /
Figure Legend:
Examples of aperture motion and long-range context effects: (a) Single stimulus with diagonal perceived drift (e.g., in direction of red arrow). (b) In the presence of orthogonally oriented contextual gratings (which each on their own may appear to drift diagonally in the direction indicated by the red arrows), all gratings appear to drift together either horizontally (yellow arrow), or (c) vertically (blue arrow), depending on the local drift direction of the context. (d) A combination of both types of context gratings produces spontaneous “multistable” switching between percepts of horizontal, vertical motion (here, in directions orthogonal to the two intersecting axes along which the context pairs are arranged), or local diagonal motion, under free viewing. In the experiments, white dots over the context gratings could be used as attentional cues (as illustrated in d), while more peripheral white dots served as cursors rotating around the center, used by the observer to indicate the vector of currently perceived central motion (in this example diagonal). (e–h) Radial histograms showing the proportional distribution of cursor positions over three bins during free viewing of the stimulus shown above each plot (averaged across 7 subjects with 95% confidence intervals). Note how the presence of horizontal and vertical components in the responses reflect the physical availability of such global motion vectors in the stimulus. Note also the “multistable” outcome for panel d, as shown in panel h.
Date of download: 12/3/2017
The Association for Research in Vision and Ophthalmology Copyright © All rights reserved.