Hostname: page-component-586b7cd67f-t7czq Total loading time: 0 Render date: 2024-11-24T06:38:06.568Z Has data issue: false hasContentIssue false

The n-back as a dual-task: P300 morphology under divided attention

Published online by Cambridge University Press:  09 January 2002

SCOTT WATTER
Affiliation:
Cognitive Psychophysiology Laboratory, The University of Queensland, Australia Department of Psychiatry, The University of Queensland, Australia
GINA M. GEFFEN
Affiliation:
Cognitive Psychophysiology Laboratory, The University of Queensland, Australia Department of Psychology, The University of Queensland, Australia
LAURIE B. GEFFEN
Affiliation:
Cognitive Psychophysiology Laboratory, The University of Queensland, Australia Department of Psychiatry, The University of Queensland, Australia
Get access

Abstract

The n-back task was hypothesized to be a dual task, permitting the imposition of parametrically increasing attentional and working memory demands, while keeping constant the demands of an embedded matching subtask. Visual targets were presented for 200 ms every 2.2 s at pseudorandomly varying positions on a computer screen. Participants were required to remember the most recent 0, 1, 2, or 3 positions and responded with a choice button push to whether the current target position matched the position presented n items previously. P300 peak latency was constant across n-back tasks, reflecting constant perceptual and cognitive demands of the matching subtask. P300 peak amplitude decreased with increasing memory load, reflecting reallocation of attention and processing capacity away from the matching subtask to working memory activity. These data support a dual-task nature of the n-back, which should be considered when employing this paradigm.

Type
SPECIAL REPORT
Copyright
© 2001 Society for Psychophysiological Research

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)