title: A working memory account of refixations in visual search.
abstract: We tested the hypothesis that active exploration of the visual environment is mediated not only by visual attention but also by visual working memory (VWM) by examining performance in both a visual search and a change detection task. Subjects rarely fixated previously examined distracters during visual search, suggesting that they successfully retained those items. Change detection accuracy decreased with increasing set size, suggesting that subjects had a limited VWM capacity. Crucially, performance in the change detection task predicted visual search efficiency: Higher VWM capacity was associated with faster and more accurate responses as well as lower probabilities of refixation. We found no temporal delay for return saccades, suggesting that active vision is primarily mediated by VWM rather than by a separate attentional disengagement mechanism commonly associated with the inhibition-of-return (IOR) effect. Taken together with evidence that visual attention, VWM, and the oculomotor system involve overlapping neural networks, these data suggest that there exists a general capacity for cognitive processing.
authors.affiliation: Rotman Research Institute, Baycrest, Toronto, Canada.
authors.forename: Kelly
authors.initials: K
authors.lastname: Shen
authors.affiliation: Rotman Research Institute, Baycrest, Toronto, Canada Department of Psychology, University of Toronto, Toronto, Canada.
authors.forename: Anthony R
authors.initials: AR
authors.lastname: McIntosh
authors.affiliation: Rotman Research Institute, Baycrest, Toronto, Canada Department of Psychology, University of Toronto, Toronto, Canada Department of Psychiatry, University of Toronto, Toronto, Canada.
authors.forename: Jennifer D
authors.initials: JD
authors.lastname: Ryan
mesh_terms: D000328:Adult; D001288:Attention / Q000502:physiology; D005260:Female; D005403:Fixation, Ocular / Q000502:physiology*; D006801:Humans; D008297:Male; D008570:Memory, Short-Term / Q000502:physiology*; D010364:Pattern Recognition, Visual / Q000502:physiology*; D011930:Reaction Time; D012438:Saccades / Q000502:physiology*
keywords: individual differences; saccades; visual search; working memory capacity