title: Relative contributions of task-relevant and task-irrelevant dimensions in priming of pop-out.
abstract: Intertrial effects such as priming of pop-out (PoP) often occur for task-irrelevant dimensions as well as task-relevant dimensions, though to a weaker extent. Here we test the hypothesis that increased priming for task-relevant dimensions is due to greater passive build-up of priming for the task-relevant dimension rather than to an active filtering of task-irrelevant dimensions; if this is the case, then we should observe a positive correlation between the magnitude of task-relevant and task-irrelevant priming. We tested this hypothesis using a pop-out search task in which the task-relevant dimension was orientation and the task-irrelevant dimension was color. We found a strong, positive association between task-relevant and task-irrelevant priming across a large group of participants (N = 100); additionally, we observed increased priming over consecutive repetitions for the task-relevant dimension, whereas task-irrelevant priming was constant across multiple repetitions. As further evidence against an active filtering account, task-irrelevant priming showed no systematic relationship with visual short-term memory capacity, which has been shown to correlate with filtering ability. Together, our results suggest that task-irrelevant dimensions are co-selected rather than filtered out during target search. Further, increased task-relevant priming may reflect an enhanced representation of the task-relevant dimension that is reinforced over consecutive repetitions.
authors.affiliation: Department of Psychology, Northwestern University, Evanston, IL, USA.
authors.forename: Audrey L
authors.initials: AL
authors.lastname: Michal
authors.affiliation: Beckman Institute Department of Psychology, University of Illinois, Urbana-Champaign, IL, USA.
authors.forename: Alejandro
authors.initials: A
authors.lastname: Lleras
authors.affiliation: Beckman Institute Department of Psychology, University of Illinois, Urbana-Champaign, IL, USA.
authors.forename: Diane M
authors.initials: DM
authors.lastname: Beck
mesh_terms: D000293:Adolescent; D001288:Attention / Q000502:physiology; D003116:Color; D003118:Color Perception / Q000502:physiology; D003463:Cues; D005260:Female; D006801:Humans; D008297:Male; D008570:Memory, Short-Term / Q000502:physiology*; D009949:Orientation / Q000502:physiology; D010364:Pattern Recognition, Visual / Q000502:physiology*; D010775:Photic Stimulation / Q000379:methods; D011597:Psychomotor Performance / Q000502:physiology; D011930:Reaction Time / Q000502:physiology; D055815:Young Adult
keywords: priming of pop-out; task-relevance; visual short term memory