Abstract
Attentional control settings bias the visual system to prioritize task-relevant features and properties in the environment. While a great deal of research has investigated the kinds of control settings at our disposal (e.g., shape, color, oddballs, etc), little is known about how individuals choose these settings. Some researchers have speculated that we choose the settings requiring the least cognitive effort. However, before this speculation can be addressed, it is necessary to determine if the amount of effort required to establish control varies across different control settings. Here, we use pupillometry to measure preparatory effort for two types of control settings. In two experiments (total N = 28), participants performed a visual search task containing two targets: an "easy" target (a salient color singleton, e.g. red amongst blue items) or a "difficult" target (a less salient shape singleton, square amongst diamonds). On each trial, participants were instructed to make a saccade to one of the two targets, which was cued by a tone at the start of the trial. We measured pupil dilation, a well-established indicator of cognitive effort, focusing specifically on the preparatory period between the tone and the presentation of the search display (3.5 seconds). In both experiments, pupil dilation was larger during preparation for the difficult shape target than the easy color target. These results show that the amount of effort required to configure attentional control varies depending on the expected target properties. Moreover, the results provide a basis for the view that effort may play a key role in how individuals choose their attentional control settings.
Meeting abstract presented at VSS 2016