Can't Take My Eyes Off of You: Delayed Attentional Disengagement Based on Attention Set

The attentional consequences of task-irrelevant properties of objects outside the focus of attention have been studied extensively (attention capture). However, the extent to which task-irrelevant properties influence attentional deployment when they are already within the focus of attention has generally been ignored. This is an important oversight because attention capture effects should be thought of as being composed of both the pull of attention to a location, and the holding of attention once it gets there. We present the results of a series of experiments examining the ability of task-relevant and irrelevant properties of the currently fixated item to hold attention (as measured by dwell times). The attentional disengagement paradigm has participants start each search trial fixating an object that could never be the search target. Surprisingly, completely irrelevant properties of this object determined how long attention dwelled and where attention went next. Task-relevant properties at this irrelevant location also increased dwell times. We present evidence that contingent disengagement effects are not restricted to simple target features. In one experiment participants viewed displays containing many circles and each trial began with participants fixating a circle that was never the target circle (the sole red circle). The task was to indicate the presence or absent of a target letter (e.g., p) within the red target circle as quickly as possible, and participants were told to ignore the initially fixated circle. However, when this initially fixated, always irrelevant item contained the target letter disengagement was significantly delayed. Additionally, when this item contained a letter similar to the target (e.g., q), disengagement was delayed compared to a dissimilar letter (e.g., i). In this series of experiments we found stimulus-driven and contingent capture effects on disengagement, and we present the disengagement paradigm as a promising means to study complex attention sets.