title: Working memory's workload capacity.
abstract: We examined the role of dual-task interference in working memory using a novel dual two-back task that requires a redundant-target response (i.e., a response that neither the auditory nor the visual stimulus occurred two back versus a response that one or both occurred two back) on every trial. Comparisons with performance on single two-back trials (i.e., with only auditory or only visual stimuli) showed that dual-task demands reduced both speed and accuracy. Our task design enabled a novel application of Townsend and Nozawa's (Journal of Mathematical Psychology 39: 321-359, 1995) workload capacity measure, which revealed that the decrement in dual two-back performance was mediated by the sharing of a limited amount of processing capacity. Relative to most other single and dual n-back tasks, performance measures for our task were more reliable, due to the use of a small stimulus set that induced a high and constant level of proactive interference. For a version of our dual two-back task that minimized response bias, accuracy was also more strongly correlated with complex span than has been found for most other single and dual n-back tasks.
authors.affiliation: Schools of Medicine and Psychology, Universitys of Tasmania and Newcastle, Sandy Bay, Tasmania, 7005, Australia. andrew.heathcote@utas.edu.au.
authors.forename: Andrew
authors.initials: A
authors.lastname: Heathcote
authors.affiliation: Department of Psychology, University of Utah, Salt Lake City, UT, USA.
authors.forename: James R
authors.initials: JR
authors.lastname: Coleman
authors.affiliation: School of Psychology, Univeristy of Newcaste, Callaghan, NSW, 2308, Australia.
authors.forename: Ami
authors.initials: A
authors.lastname: Eidels
authors.affiliation: Department of Psychology, University of Utah, Salt Lake City, UT, USA.
authors.forename: Jason M
authors.initials: JM
authors.lastname: Watson
authors.affiliation: Department of Psychology, Wright State University, Dayton, OH, USA.
authors.forename: Joseph
authors.initials: J
authors.lastname: Houpt
authors.affiliation: Department of Psychology, University of Utah, Salt Lake City, UT, USA.
authors.forename: David L
authors.initials: DL
authors.lastname: Strayer
mesh_terms: D000328:Adult; D001288:Attention / Q000502:physiology*; D056344:Executive Function / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008570:Memory, Short-Term / Q000502:physiology*; D011597:Psychomotor Performance / Q000502:physiology*; D055815:Young Adult
keywords: Multitasking; Proactive interference; Systems factorial technology; Working memory; Workload capacity; n-Back task