title: The Adjusting-Paced Serial Addition Test (Adjusting-PSAT): thresholds for speed of information processing as a function of stimulus modality and problem complexity.
abstract: A modified computer version of the PASAT (Adjusting-PSAT; ) is described that measures speed of information processing and working memory by means of a temporal threshold rather than number of correct responses. This is accomplished by making the duration of the interval between numbers depend on the correctness of responding-a correct response decreases the interval between digits and an incorrect response increases the interval. Modality of presentation (visual and auditory) was factorially combined with problem difficulty (answers between 2-10 or 2-18). Performance of 60 healthy student volunteers on the Adjusting-PSAT was compared to that obtained on several traditional neuropsychological measures (Digit Span, Trail Making Test, and Symbol Digit Modality Test) and on a test of basic addition skills. The visual version of the test produced a lower threshold than did the auditory version, but problem difficulty did not produce a significant effect. Of the neuropsychological tests, Trails-B (TMT-B) was most highly correlated with thresholds. However, regression analyses revealed that math ability accounted for more variance than did TMT-B. The clinical implications of these finding are discussed.
authors.affiliation: University of Victoria, BC, Victoria, Canada.
authors.forename: J
authors.initials: J
authors.lastname: Royan
authors.forename: T N
authors.initials: TN
authors.lastname: Tombaugh
authors.forename: L
authors.initials: L
authors.lastname: Rees
authors.forename: M
authors.initials: M
authors.lastname: Francis
mesh_terms: D000161:Acoustic Stimulation; D000293:Adolescent; D000328:Adult; D003936:Diagnosis, Computer-Assisted; D006801:Humans; D008433:Mathematics; D008606:Mental Processes; D009483:Neuropsychological Tests; D010775:Photic Stimulation; D011340:Problem Solving; D012016:Reference Values; D013997:Time Factors