title: Memory activation reveals abnormal EEG in preclinical Huntington's disease.
abstract: The EEG is potentially useful as a marker of early Huntington's disease (HD). In dementia, the EEG during a memory activation challenge showed abnormalities where the resting EEG did not. We investigated whether memory activation also reveals EEG abnormalities in preclinical HD. Sixteen mutation carriers for HD and 13 nonmutation carriers underwent neurological, neuropsychological, MRI and EEG investigations. The EEG was registered during a rest condition, i.e. eyes closed, and a working memory task. In each condition we determined absolute power in the theta (4-8 Hz) and alpha (8-13 Hz) bands and subsequently calculated relative alpha power. The EEG during eyes closed did not differ between groups. The EEG during memory activation showed less relative alpha power in mutation carriers as compared to nonmutation carriers, even though memory performance was similar [F (1,27) = 10.87; P = 0.003]. Absolute powers also showed less alpha power [F (1,27) = 7.02; P = 0.013] but similar theta power. No correlations were found between absolute and relative alpha power on the one hand and neuropsychological scores, motor scores or number of CAG repeats on the other. In conclusion, memory activation reveals functional brain changes in Huntington's disease before clinical signs become overt.
authors.affiliation: Section of Neuropsychology, Department of Neurology, Leiden University Medical Center, Leiden, The Netherlands. k.van_der_hiele@lumc.nl
authors.forename: Karin
authors.initials: K
authors.lastname: van der Hiele
authors.forename: Caroline K
authors.initials: CK
authors.lastname: Jurgens
authors.forename: Alla A
authors.initials: AA
authors.lastname: Vein
authors.forename: Robert H A M
authors.initials: RH
authors.lastname: Reijntjes
authors.forename: Marie-Noëlle W
authors.initials: MN
authors.lastname: Witjes-Ané
authors.forename: Raymund A C
authors.initials: RA
authors.lastname: Roos
authors.forename: Gert
authors.initials: G
authors.lastname: van Dijk
authors.forename: Huub A M
authors.initials: HA
authors.lastname: Middelkoop
mesh_terms: D000328:Adult; D000513:Alpha Rhythm; D002540:Cerebral Cortex / Q000503:physiopathology*; D042241:Early Diagnosis; D004569:Electroencephalography; D005260:Female; D006580:Genetic Carrier Screening; D006801:Humans; D006816:Huntington Disease / Q000175:diagnosis* / Q000235:genetics / Q000503:physiopathology; D008297:Male; D008570:Memory, Short-Term / Q000502:physiology*; D008875:Middle Aged; D009460:Neurologic Examination; D009483:Neuropsychological Tests; D011237:Predictive Value of Tests; D013826:Theta Rhythm; D018911:Trinucleotide Repeats