title: Impairment of incidental memory for frequency in patients with obsessive-compulsive disorder.
abstract: The aim of our study was to investigate whether patients with obsessive-compulsive disorder (OCD) have impaired incidental memory for frequency. Fifty-four subjects (27 OCD patients and 27 matched control subjects) performed a task assessing estimation of occurrence of previously heard words. Performance on this task was compared with other intentional verbal memory tasks (recognition, recall and learning of common words). We also correlated memory for frequency with frontal lobe tests (Wisconsin Card Sorting Test, Trail Making Tests A and B, and verbal fluency). Performance on incidental learning of frequency was significantly worse in the OCD group than in control subjects. Other verbal memory measures did not show significant differences. Performance in the frequency task correlated with verbal fluency. Although intentional verbal memories are normal in OCD patients, incidental memory for frequency is impaired, suggesting that prefrontal systems are involved in OCD.
authors.affiliation: Departament de Psiquiatria i Psicobiologia Clínica, Universitat de Barcelona, Passeig de la Vall d'Hebron 171, E-08035 Barcelona, Spain. ajurado@psi.ub.es
authors.forename: M A
authors.initials: MA
authors.lastname: Jurado
authors.forename: C
authors.initials: C
authors.lastname: Junqué
authors.forename: J
authors.initials: J
authors.lastname: Vallejo
authors.forename: P
authors.initials: P
authors.lastname: Salgado
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D005260:Female; D005625:Frontal Lobe / Q000503:physiopathology; D006801:Humans; D015994:Incidence; D008297:Male; D008569:Memory Disorders / Q000175:diagnosis / Q000453:epidemiology* / Q000503:physiopathology; D008875:Middle Aged; D009483:Neuropsychological Tests; D009771:Obsessive-Compulsive Disorder / Q000175:diagnosis / Q000453:epidemiology* / Q000503:physiopathology; D012720:Severity of Illness Index; D013702:Temporal Lobe / Q000503:physiopathology; D014706:Verbal Learning / Q000502:physiology