Alejandro Lleras, PhD

Speaker

Alejandro Lleras, PhD
Professor, Department of Psychology
University of Illinois Urbana Champaign
Host: Vision Science Student DEIB Committee

Date and Time

Monday, April 10, 2023
11:10 am - 12:30 pm

Location

Room 489 Minor Hall

Alejandro Lleras's Abstract

Towards a more precise understanding of distractor rejection processes.

When looking for a specific target in a scene, a fast and efficient analysis of the scene involves using peripheral vision to discard locations that are unlikely to contain the target prior to directing focused attention or eye movements towards target-likely locations. Recently, we proposed that the efficiency of this non-target (i.e., distractor) rejection process in the periphery is determined by the target-distractor contrast, which is a hypothesized visual distinctiveness signal that differentiates the visual characteristics of the target from those of the distractor. The larger the target-distractor contrast, the faster the evidence to reject that distractor accumulates. By relying on behavioral and computational modeling approaches, we use this conceptualization to quantify the processes that contribute to non-target rejection and answer questions such as: how do distinctiveness signals across different visual dimensions combine to determine the overall distinctiveness of a target? What situations preempt this combination? What happens when different types of distractors are present in the scene? And, how does the spatial distribution of distractors impact the distinctiveness of a target?