title: Working memory capacity and redundant information processing efficiency.
abstract: Working memory capacity (WMC) is typically measured by the amount of task-relevant information an individual can keep in mind while resisting distraction or interference from task-irrelevant information. The current research investigated the extent to which differences in WMC were associated with performance on a novel redundant memory probes (RMP) task that systematically varied the amount of to-be-remembered (targets) and to-be-ignored (distractor) information. The RMP task was designed to both facilitate and inhibit working memory search processes, as evidenced by differences in accuracy, response time, and Linear Ballistic Accumulator (LBA) model estimates of information processing efficiency. Participants (N = 170) completed standard intelligence tests and dual-span WMC tasks, along with the RMP task. As expected, accuracy, response-time, and LBA model results indicated memory search and retrieval processes were facilitated under redundant-target conditions, but also inhibited under mixed target/distractor and redundant-distractor conditions. Repeated measures analyses also indicated that, while individuals classified as high (n = 85) and low (n = 85) WMC did not differ in the magnitude of redundancy effects, groups did differ in the efficiency of memory search and retrieval processes overall. Results suggest that redundant information reliably facilitates and inhibits the efficiency or speed of working memory search, and these effects are independent of more general limits and individual differences in the capacity or space of working memory.
authors.affiliation: Department of Health, Behavioral Health Administration Honolulu, HI, USA ; Department of Psychology, University of Hawaii Honolulu, HI, USA.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Endres
authors.affiliation: Department of Psychology, Wright State University Dayton, OH, USA.
authors.forename: Joseph W
authors.initials: JW
authors.lastname: Houpt
authors.affiliation: School of Psychology, University of New South Wales Sydney, NSW, Australia.
authors.forename: Chris
authors.initials: C
authors.lastname: Donkin
authors.affiliation: Department of Psychological and Brain Sciences, Indiana University Bloomington, IN, USA.
authors.forename: Peter R
authors.initials: PR
authors.lastname: Finn
keywords: individual differences; linear ballistic accumulator; memory retrieval; systems factorial technology; working memory capacity