Masters Thesis

Involuntary conscious entry occurs for visually salient objects: a paradigm for EEG

Stimulus-driven capture of attention has been used extensively in visual search tasks to examine the automatic deployment of attention. Few studies have examined the attention capture ability of salient singletons when the task requires the participant to not attend to anything. In these studies, involving a variant of the Reflexive Imagery Task, participants were presented with an array of six objects and instructed to not think of the name (subvocalize) of any of the objects presented. In Study 1, another condition instructed participants to subvocalize the name of any of the objects. On half of the critical trials, one object was presented in a color that differed from that of all the other objects (the Singleton condition). In this condition, the subvocalization was for the critical stimulus on a high proportion of the trials for both the voluntary and involuntary conditions. Study 2 included conjunction trials which contained target stimuli defined by two features (color and motion). The attention capture effect was not observed for the conjunction trials, but it was enhanced for trials with a flashing singleton. These results provide evidence that the visual saliency of an object influences which representations enter into consciousness, regardless of whether one intends to attend to the object or not. This finding has implications for advertising and the design of user interfaces.