Abstract
Spatial cues can direct attention toward a particular location in the visual field. Prinzmetal, Park, and McCool (2005) proposed that two distinct types of attention are engaged by these spatial cues. Voluntary attention is engaged when the cues are predictive of the target's location and serves to facilitate the perceptual representation of the object (evidenced by increased accuracy of the response following a valid cue), as well as indicate the location of the target (evidenced by a faster response following a valid cue). Involuntary attention is engaged whether the cues are predictive or not and serves to select an object for a response, which is reflected in faster response times, but does not increase the accuracy of the perceptual representation. The goal of the present study was to test the dissociation between these two types of attention within the response time domain. Participants made speeded responses indicating the direction of an arrow that appeared in either the spatially cued (valid) or uncued (invalid) location. Separate groups of participants performed the task with predictive cues, to invoke voluntary attention, or nonpredictive cues, to invoke only involuntary attention. A small priming arrow appeared prior to the onset of the target arrow for 50 ms. The reaction time effect of this prime provided an index of perceptual enhancement. Faster response times were recorded for valid trails, but a larger priming effect was observed only when the prime appeared in the cued location and when voluntary attention was invoked, consistent with the proposal that voluntary and involuntary attention play distinct computational roles.