title: Fronto-parietal coupling of brain rhythms in mild cognitive impairment: a multicentric EEG study.
abstract: Electroencephalographic (EEG) data were recorded in 69 normal elderly (Nold), 88 mild cognitive impairment (MCI), and 109 mild Alzheimer's disease (AD) subjects at rest condition, to test whether the fronto-parietal coupling of EEG rhythms is in line with the hypothesis that MCI can be considered as a pre-clinical stage of the disease at group level. Functional coupling was estimated by synchronization likelihood of Laplacian-transformed EEG data at electrode pairs, which accounts for linear and non-linear components of that coupling. Cortical rhythms of interest were delta (2-4Hz), theta (4-8Hz), alpha 1 (8-10.5Hz), alpha 2 (10.5-13Hz), beta 1 (13-20Hz), beta 2 (20-30Hz), and gamma (30-40Hz). Compared to the Nold subjects, the AD patients presented a marked reduction of the synchronization likelihood (delta to gamma) at both fronto-parietal and inter-hemispherical (delta to beta 2) electrodes. As a main result, alpha 1 synchronization likelihood progressively decreased across Nold, MCI, and mild AD subjects at midline (Fz-Pz) and right (F4-P4) fronto-parietal electrodes. The same was true for the delta synchronization likelihood at right fronto-parietal electrodes (F4-P4). For these EEG bands, the synchronization likelihood correlated with global cognitive status as measured by the Mini Mental State Evaluation. The present results suggest that at group level, fronto-parietal coupling of the delta and alpha rhythms progressively becomes abnormal though MCI and mild AD. Future longitudinal research should evaluate whether the present EEG approach is able to predict the cognitive decline in individual MCI subjects.
authors.affiliation: Dipartimento di Fisiologia Umana e Farmacologia, Università degli Studi di Roma La Sapienza, Piazzale Aldo Moro 5, 00185 Rome, Italy. claudio.babiloni@uniroma1.it
authors.forename: Claudio
authors.initials: C
authors.lastname: Babiloni
authors.forename: Raffaele
authors.initials: R
authors.lastname: Ferri
authors.forename: Giuliano
authors.initials: G
authors.lastname: Binetti
authors.forename: Andrea
authors.initials: A
authors.lastname: Cassarino
authors.forename: Gloria
authors.initials: G
authors.lastname: Dal Forno
authors.forename: Matilde
authors.initials: M
authors.lastname: Ercolani
authors.forename: Florinda
authors.initials: F
authors.lastname: Ferreri
authors.forename: Giovanni B
authors.initials: GB
authors.lastname: Frisoni
authors.forename: Bartolo
authors.initials: B
authors.lastname: Lanuzza
authors.forename: Carlo
authors.initials: C
authors.lastname: Miniussi
authors.forename: Flavio
authors.initials: F
authors.lastname: Nobili
authors.forename: Guido
authors.initials: G
authors.lastname: Rodriguez
authors.forename: Francesco
authors.initials: F
authors.lastname: Rundo
authors.forename: Cornelis J
authors.initials: CJ
authors.lastname: Stam
authors.forename: Toshimitsu
authors.initials: T
authors.lastname: Musha
authors.forename: Fabrizio
authors.initials: F
authors.lastname: Vecchio
authors.forename: Paolo M
authors.initials: PM
authors.lastname: Rossini
mesh_terms: D000368:Aged; D000544:Alzheimer Disease / Q000503:physiopathology; D003072:Cognition Disorders / Q000503:physiopathology*; D003344:Cortical Synchronization; D004569:Electroencephalography; D005260:Female; D005625:Frontal Lobe / Q000503:physiopathology*; D006801:Humans; D008297:Male; D010296:Parietal Lobe / Q000503:physiopathology*