Abstract
Visual information was traditionally thought to flow from the perception to the memory. Over time, however, it has become clear that memory of various forms plays a role in perception. Priors influence best inferences and context can facilitate recognition. But the role of memory is typically thought of in terms of long-term memory. We sought to investigate the possibility that the contents of visual working memory influence online perception. In each trial of our experiment one of three Ponzo railway figures was presented, and participants were instructed to remember the figures, about which they were also probed in a subsequent change detection paradigm. Critically, during the delay period of the change detection task, two horizontal lines appeared for 100 ms, and participants made an online judgment identifying the longer of the two lines. In 50% of trials the two lines were actually equal in length. But results showed that the line near the narrow end of the memorized Ponzo figure was typically perceived to be longer. (An effect in the same direction was obtained in the trials with lines that differed in length.) We ruled out the possibility that the effect was caused by an afterimage in three more experiments: a) increasing the delay time from the Ponzo figure to the two lines, b) adding a white noise mask after the Ponzo figure, and c) adding a random line mask after the Ponzo figure. These experiments replicated the effect —the figure in memory influenced the perception of line length from trial to trial. These results are consistent with recent work demonstrating that visual working memory activates early visual cortex in content specific ways. And more broadly, they suggest that the current contents of visual working memory support online perception.
Meeting abstract presented at VSS 2014