title: Re-evaluating the relationships among filtering activity, unnecessary storage, and visual working memory capacity.
abstract: The amount of task-irrelevant information encoded in visual working memory (VWM), referred to as unnecessary storage, has been proposed as a potential mechanism underlying individual differences in VWM capacity. In addition, a number of studies have provided evidence for additional activity that initiates the filtering process originating in the frontal cortex and basal ganglia, and is therefore a crucial step in the link between unnecessary storage and VWM capacity. Here, we re-examine data from two prominent studies that identified unnecessary storage activity as a predictor of VWM capacity by directly testing the implied path model linking filtering-related activity, unnecessary storage, and VWM capacity. Across both studies, we found that unnecessary storage was not a significant predictor of individual differences in VWM capacity once activity associated with filtering was accounted for; instead, activity associated with filtering better explained variation in VWM capacity. These findings suggest that unnecessary storage is not a limiting factor in VWM performance, whereas neural activity associated with filtering may play a more central role in determining VWM performance that goes beyond preventing unnecessary storage.
authors.affiliation: Department of Psychology, Brock University, 500 Glenridge Ave, St Catharines, Ontario, L2S 3A1, Canada, semrich@brocku.ca.
authors.forename: Stephen M
authors.initials: SM
authors.lastname: Emrich
authors.forename: Michael A
authors.initials: MA
authors.lastname: Busseri
mesh_terms: D001288:Attention / Q000502:physiology; D001921:Brain / Q000502:physiology*; D004569:Electroencephalography; D006801:Humans; D008279:Magnetic Resonance Imaging; D008570:Memory, Short-Term / Q000502:physiology*; D008959:Models, Neurological; D008960:Models, Psychological; D009483:Neuropsychological Tests; D010364:Pattern Recognition, Visual / Q000502:physiology*