title: The validity of d prime as a working memory index: results from the "Bergen n-back task".
abstract: The n-back task is frequently used as an experimental paradigm in imaging studies of working memory. This study aimed to investigate whether the Bergen 2-back task is suitable for use in desktop assessment of patients with schizophrenia. Looking at the psychometric properties of the task, including the newly added measure of discriminability, d prime (d '), our analyses confirmed that the 2-back d ' is the preferred measure of working memory dysfunction in desktop assessment compared to the Digit Span Backward and the Letter-Number Sequencing subtests from the Wechsler Adult Intelligence Scale-Third Edition (WAIS-III). d ' has the advantage of capturing executive skills needed to perform mental operations in patients with schizophrenia, without being influenced by demographic variables or IQ.
authors.affiliation: Department of Psychiatry, Oslo University Hospital, Ullevaal, Norway. b.c.haatveit@medisin.uio.no
authors.forename: Beathe C
authors.initials: BC
authors.lastname: Haatveit
authors.forename: Kjetil
authors.initials: K
authors.lastname: Sundet
authors.forename: Kenneth
authors.initials: K
authors.lastname: Hugdahl
authors.forename: Torill
authors.initials: T
authors.lastname: Ueland
authors.forename: Ingrid
authors.initials: I
authors.lastname: Melle
authors.forename: Ole A
authors.initials: OA
authors.lastname: Andreassen
mesh_terms: D000293:Adolescent; D000328:Adult; D016009:Chi-Square Distribution; D005260:Female; D006801:Humans; D008297:Male; D008569:Memory Disorders / Q000175:diagnosis / Q000209:etiology*; D008570:Memory, Short-Term / Q000502:physiology*; D008875:Middle Aged; D009483:Neuropsychological Tests; D015203:Reproducibility of Results; D012559:Schizophrenia / Q000150:complications*; D012565:Schizophrenic Psychology; D018709:Statistics, Nonparametric; D055815:Young Adult