title: Is the n-back task a valid neuropsychological measure for assessing working memory?
abstract: The n-back is a putative working memory task frequently used in neuroimaging research; however, literature addressing n-back use in clinical neuropsychological evaluation is sparse. We examined convergent validity of the n-back with an established measure of working memory, digit span backward. The relationship between n-back performance and scores on measures of processing speed was also examined, as was the ability of the n-back to detect potential between-groups differences in control and Parkinson's disease (PD) groups. Results revealed no correlation between n-back performance and digit span backward. N-back accuracy significantly correlated with a measure of processing speed (Trail Making Test Part A) at the 2-back load. Relative to controls, PD patients performed less accurately on the n-back and showed a trend toward slower reaction times, but did not differ on any of the neuropsychological measures. Results suggest the n-back is not a pure measure of working memory, but may be able to detect subtle differences in cognitive functioning between PD patients and controls.
authors.affiliation: Department of Clinical and Health Psychology, College of Public Health and Health Professions, University of Florida, FL, USA. Kimberly.Miller9@va.gov
authors.forename: K M
authors.initials: KM
authors.lastname: Miller
authors.forename: C C
authors.initials: CC
authors.lastname: Price
authors.forename: M S
authors.initials: MS
authors.lastname: Okun
authors.forename: H
authors.initials: H
authors.lastname: Montijo
authors.forename: D
authors.initials: D
authors.lastname: Bowers
mesh_terms: D000328:Adult; D000368:Aged; D000704:Analysis of Variance; D001288:Attention / Q000502:physiology; D056344:Executive Function / Q000502:physiology; D005260:Female; D006801:Humans; D008297:Male; D008570:Memory, Short-Term / Q000502:physiology*; D008875:Middle Aged; D009483:Neuropsychological Tests; D010300:Parkinson Disease / Q000503:physiopathology*; D011597:Psychomotor Performance / Q000502:physiology; D011930:Reaction Time / Q000502:physiology