Abstract
Background. Location specificity is a hallmark of perceptual learning: performance improvements are usually confined to trained retinal locations. Previously, we showed that training with valid exogenous cues facilitates transfer of learning to untrained locations in an orientation discrimination task, increasing asymptotic performance at high contrasts at both trained and untrained locations.Here, we investigated the yet-unknown influence of endogenous spatial attention on perceptual learning and characterized its influence on location specificity. Method. Before and after training, participants were tested on an orientation discrimination task at four peripheral locations. Participants trained for 3 sessions at two locations. Targets were Gabors of varying contrast (2-64%) oriented clockwise or counter-clockwise relative to vertical. The Attention group (n=12) received 100% valid endogenous spatial pre-cues which instructed participants to pay attention to one of the trained locations on each trial. The Neutral group (n=12) received uninformative cues, which indicated the two locations where a target may appear. During the Pre- and Post-Tests, all participants received neutral cues. Learning was assessed at the Trained and Untrained locations separately by comparing performance on the Post-Test to that of the Pre-Test. Results. In the Attention group, thresholds improved between the Pre- and Post-Tests for both the Trained and Untrained locations. In the Neutral group, thresholds improved for the Trained locations, but not for the Untrained locations. Model comparisons confirmed that changes in only threshold accounted for learning at the Trained location of the Neutral group, and Trained as well as Untrained locations in the Attention group. Conclusions. Training with endogenous attention, similar to exogenous attention, enables transfer to untrained locations. Unlike exogenous attention, which mostly influences the asymptote of the contrast sensitivity function, endogenous attention influences the threshold, suggesting distinct mechanisms for the influence of endogenous and exogenous attention on perceptual learning and location transfer.
Meeting abstract presented at VSS 2018