Abstract
Peripheral semantic distractors capture spatiotemporal attention. We investigate whether spatiotemporal attentional capture occurs for peripheral distracting information that does not reach consciousness because it loses the competition for figural assignment. Subjects categorized a centrally-presented word as "natural" or "artificial." 110 ms before the word, two novel silhouettes were presented (80 ms) above and below fixation. Silhouettes were biased so that the inside was perceived as the figure and the outside was perceived as a shapeless ground. In Experiment 1, on experimental trials, portions of familiar objects were suggested (but not consciously perceived) on the groundside of one of the silhouettes (half natural, half artificial; crossed with target word category); nothing familiar was suggested on the groundside of the other silhouette. On control trials, nothing familiar was suggested on the groundside of either silhouette. On Experiment 2 experimental trials both silhouettes suggested the same familiar object on the groundside. Semantic priming from the category of the groundside object should affect word categorization, decreasing RTs when the category of the word and the ground object are the same relative to both control trials and different-category trials (Cacciamani, et al. 2014). Semantic priming was observed in both experiments: word categorization RTs were faster on experimental same-category than different-category trials (ps < 0.01). Unlike previous results obtained with these silhouettes, different-category RTs were longer than control RTs (ps < 0.01), whereas same-category RTs and control RTs did not differ statistically. We propose that for same-category trials, slowing due to capture summed with speeding due to semantic facilitation, thereby erasing the typical facilitatory effect. For different-category trials the slowing may be due to capture alone or to capture summed with interference. These data are the first to show that peripheral distracting information that does not reach consciousness can capture attention and prime categorization responses.
Meeting abstract presented at VSS 2016