title: Effects of frontal lobe damage on interference effects in working memory.
abstract: Working memory is hypothesized to comprise a collection of distinct components or processes, each of which may have a unique neural substrate. Recent neuroimaging studies have isolated a region of the left inferior frontal gyrus that appears to be related specifically to one such component: resolving interference from previous items in working memory. In the present study, we examined working memory in patients with unilateral frontal lobe lesions by using a modified version of an item recognition task in which interference from previous trials was manipulated. In particular, we focused on patient R.C., whose lesion uniquely impinged on the region identified in the neuroimaging studies of interference effects. We measured baseline working memory performance and interference effects in R.C. and other frontal patients and in age-matched control subjects and young control subjects. Comparisons of each of these groups supported the following conclusions. Normal aging is associated with changes to both working memory and interference effects. Patients with frontal damage exhibited further declines in working memory but normal interference effects, with the exception of R.C., who exhibited a pronounced interference effect on both response time and accuracy. We propose that the left inferior frontal gyrus subserves a general, nonmnemonic function of selecting relevant information in the face of competing alternatives and that this function may be required by some working memory tasks.
authors.affiliation: Department of Psychology, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6196, USA. thompson@psych.upenn.edu
authors.forename: Sharon L
authors.initials: SL
authors.lastname: Thompson-Schill
authors.forename: John
authors.initials: J
authors.lastname: Jonides
authors.forename: Christy
authors.initials: C
authors.lastname: Marshuetz
authors.forename: Edward E
authors.initials: EE
authors.lastname: Smith
authors.forename: Mark
authors.initials: M
authors.lastname: D'Esposito
authors.forename: Irene P
authors.initials: IP
authors.lastname: Kan
authors.forename: Robert T
authors.initials: RT
authors.lastname: Knight
authors.forename: Diane
authors.initials: D
authors.lastname: Swick
mesh_terms: D007839:Functional Laterality / Q000502:physiology; D006801:Humans; D002538:Intracranial Arteriovenous Malformations / Q000150:complications / Q000175:diagnosis; D008279:Magnetic Resonance Imaging; D008569:Memory Disorders / Q000175:diagnosis* / Q000453:epidemiology / Q000209:etiology; D020768:Middle Cerebral Artery / Q000000981:diagnostic imaging / Q000473:pathology; D017397:Prefrontal Cortex / Q000000981:diagnostic imaging / Q000473:pathology; D011930:Reaction Time; D012720:Severity of Illness Index; D014055:Tomography, Emission-Computed; D014057:Tomography, X-Ray Computed