Abstract
Humans show large individual differences in peripheral processing ability on a variety of tasks (Strasburger, Rentschler, & Jüttner, 2011). Yet, little is known about how these individual differences in peripheral processing influence humans’ perceptual learning ability. Here, we relate peripheral processing detection performance of individuals to their ability to optimize their eye movements and improve perceptual performance in a visual search task with uncertainty about the location of the target. Methods: We first measured observers’ accuracy at detecting a vertically oriented Gabor target (8 cycles/degree) embedded in white noise at various eccentricities in the visual field (visibility map). Subsequently, observers participated in a yes/no search task (12 sessions of 100 trials) for a Gabor target (50% probability of target presence) embedded in a field (29.6°x 22.2°) of dynamic white noise. The target was located five degrees from initial fixation and appeared for 700ms. Participants performed the task with no knowledge about the target location, but were informed that, if present, the target would always appear at the same location. Results: Observers with high detectability (mean d’=0.7±0.09) of the target at 5° from central fixation showed the greatest perceptual performance improvement between the first and last 100 trials (change in proportion correct, ΔPC=0.43±0.04), the highest optimization in oculomotor planning (change in mean saccade endpoint distance to target locations: Δdist=4.02±0.36°), and highest accuracy in their post-experiment explicit reports of the target location (distance of reported location from target=1.01±.27°). Observers with poorer peripheral processing at the target eccentricity (mean d’=0.11±0.11%, n=2) showed smaller improvements in perceptual performance (ΔPC=0.11±0.07), reduced optimization of their saccades (Δdist=0.30±0.05°), and lower accuracy in their post-experiment explicit report of the target location (distance from target=4.92±.04°). Conclusion: Our results suggest that differences in peripheral processing can affect an observer’s ability to optimize their saccadic planning and hinder perceptual learning.
Meeting abstract presented at VSS 2013