Importance of Task Set in the Orienting of Visual Attention

Abstract

Visual attention can be allocated to different locations of the visual field at different times resulting in improved processing of stimuli presented then and there. Understanding how attention is deployed is important due to its involvement in how we perceive and interpret the external world. The orienting of attention, both voluntarily and involuntarily, in response to presentations of different stimuli is investigated in the current dissertation. Chapter 1 investigated how attention is oriented in response to feature cues predicting the timing and location of a subsequent target when observers have prior knowledge of where targets are likely to appear at different times. Results show that observers can flexibly incorporate the different types of predictors in service of their task. Chapters 2 and 3 investigated whether unconsciously processed objects can attract attention involuntarily when object categories are relevant to task goals. Chapter 2 uncovered an attentional cost when stimuli with unconsciously processed category membership information were presented than when control stimuli were presented. This behavioral cost was dependent upon the category information being related to the task performed. Chapter 3 further investigated the attentional cost and demonstrated attentional capture in a temporal paradigm – showing that attention was not reallocated following unconsciously processed category information. Together, the three studies expand our understanding of how attention is oriented, both voluntarily and involuntarily, based upon task set and different types of predictors. The dissertation stresses the importance of considering the context of the experimental task when interpreting results.