Attentional blink: Restricted attention necessitates conscious perception

Abstract

In attention capture studies, a target stimulus is poorly identified when presented 200-500 ms after the presentation of a task-relevant distractor, a phenomenon referred to as the attentional blink. Evidence regarding the necessity of consciously perceiving the distractor in yielding an attentional blink is inconsistent in the literature. The goal of this thesis was to clarify under which conditions conscious perception of a distractor is necessary to trigger an attentional blink. It was hypothesized that the presence of a blink would vary according to the predictions of the novel restricted attention hypothesis, such that additional conditions must be met for a distractor to capture attention and cause a blink. The results provide evidence for this hypothesis, such that attention becomes restricted when attention is deployed broadly. Critically, it was found that conscious perception was a necessary condition in triggering a blink only when attention was deployed broadly. It was suggested that conscious perception becomes necessary in such conditions because it is responsible for shifting attention to the location of interest. This finding was interpreted through the novel diffused attention model. The present thesis clarifies when and why conscious perception becomes necessary. Keywords: attentional blink, attention capture, contingent capture, conscious perception