title: Cognitive impairment in amyotrophic lateral sclerosis: evidence from neuropsychological investigation and event-related potentials.
abstract: The presence of subclinical cognitive impairment in patients with amyotrophic lateral sclerosis (ALS) is investigated using neuropsychological assessment and event-related potential recordings (ERP). An extensive battery of neuropsychological tests assessing the domains of attention, memory, language, visuo-spatial and executive functions were administered to 20 non-demented patients with sporadic ALS and 13 age- and education-matched healthy control subjects. Mismatch negativity (MMN), P3b, P3a (novelty P300) and contingent negative variation (CNV) were recorded. ALS patients were significantly impaired in tests of working memory, sustained attention, response inhibition, naming, verbal fluency and complex visuo-spatial processing. The memory impairment seemed to be secondary to deficits in forming learning strategies and retrieval. In ERP recordings, P3a and P3b amplitudes of ALS patients were lower compared with the controls, P3a latencies were significantly longer and mean CNV amplitudes were higher. These results indicate subclinical impairment of cognitive functions in patients with ALS. The pattern of cognitive impairment suggests the dysfunction of the frontal network.
authors.affiliation: University of Istanbul, Istanbul Medical School, Department of Neurology, Behavioral Neurology and Movement Disorders Unit, Istanbul, Turkey.
authors.forename: Hasmet A
authors.initials: HA
authors.lastname: Hanagasi
authors.forename: I Hakan
authors.initials: IH
authors.lastname: Gurvit
authors.forename: Numan
authors.initials: N
authors.lastname: Ermutlu
authors.forename: Gulustu
authors.initials: G
authors.lastname: Kaptanoglu
authors.forename: Sacit
authors.initials: S
authors.lastname: Karamursel
authors.forename: Halil A
authors.initials: HA
authors.lastname: Idrisoglu
authors.forename: Murat
authors.initials: M
authors.lastname: Emre
authors.forename: Tamer
authors.initials: T
authors.lastname: Demiralp
mesh_terms: D000328:Adult; D000690:Amyotrophic Lateral Sclerosis / Q000503:physiopathology* / Q000523:psychology*; D000704:Analysis of Variance; D003072:Cognition Disorders / Q000175:diagnosis / Q000503:physiopathology* / Q000523:psychology*; D005071:Evoked Potentials / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests / Q000706:statistics & numerical data; D018709:Statistics, Nonparametric