title: Scopolamine effects on functional brain connectivity: a pharmacological model of Alzheimer's disease.
abstract: Scopolamine administration may be considered as a psychopharmacological model of Alzheimer's disease (AD). Here, we studied a group of healthy elderly under scopolamine to test whether it elicits similar changes in brain connectivity as those observed in AD, thereby verifying a possible model of AD impairment. We did it by testing healthy elderly subjects in two experimental conditions: glycopyrrolate (placebo) and scopolamine administration. We then analyzed magnetoencephalographic (MEG) data corresponding to both conditions in resting-state with eyes closed. This analysis was performed in source space by combining a nonlinear frequency band-specific measure of functional connectivity (phase locking value, PLV) with network analysis methods. Under scopolamine, functional connectivity between several brain areas was significantly reduced as compared to placebo, in most frequency bands analyzed. Besides, regarding the two complex network indices studied (clustering and shortest path length), clustering significantly decreased in the alpha band while shortest path length significantly increased also in alpha band both after scopolamine administration. Overall our findings indicate that both PLV and graph analysis are suitable tools to measure brain connectivity changes induced by scopolamine, which causes alterations in brain connectivity apparently similar to those reported in AD.
authors.affiliation: Laboratory of Cognitive and Computational Neuroscience (UCM-UPM). Centre for Biomedical Technology (CTB), Madrid, Spain.
authors.forename: R
authors.initials: R
authors.lastname: Bajo
authors.affiliation: Laboratory of Cognitive and Computational Neuroscience (UCM-UPM). Centre for Biomedical Technology (CTB), Madrid, Spain.
authors.forename: S
authors.initials: S
authors.lastname: Pusil
authors.affiliation: Laboratory of Cognitive and Computational Neuroscience (UCM-UPM). Centre for Biomedical Technology (CTB), Madrid, Spain.
authors.forename: M E
authors.initials: ME
authors.lastname: López
authors.affiliation: Laboratory of Cognitive and Computational Neuroscience (UCM-UPM). Centre for Biomedical Technology (CTB), Madrid, Spain.
authors.forename: L
authors.initials: L
authors.lastname: Canuet
authors.affiliation: Department of Industrial Engineering &Institute for Biomedical Technology (ITB). University of La Laguna, Spain.
authors.forename: E
authors.initials: E
authors.lastname: Pereda
authors.affiliation: BioMag Laboratory, Engineering Centre, Helsinki University Central Hospital, Helsinki, Finland.
authors.forename: D
authors.initials: D
authors.lastname: Osipova
authors.affiliation: Laboratory of Cognitive and Computational Neuroscience (UCM-UPM). Centre for Biomedical Technology (CTB), Madrid, Spain.
authors.forename: F
authors.initials: F
authors.lastname: Maestú
authors.affiliation: 1] BioMag Laboratory, Engineering Centre, Helsinki University Central Hospital, Helsinki, Finland [2] Department of Neurology, University of Helsinki, Helsinki, Finland.
authors.forename: E
authors.initials: E
authors.lastname: Pekkonen
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000188:drug therapy* / Q000503:physiopathology; D001921:Brain / Q000502:physiology*; D001931:Brain Mapping; D005260:Female; D006024:Glycopyrrolate / Q000008:administration & dosage; D006801:Humans; D015225:Magnetoencephalography; D008297:Male; D008875:Middle Aged; D009434:Neural Pathways; D015990:Placebo Effect; D012146:Rest; D012601:Scopolamine / Q000008:administration & dosage*
chemical_list: D012601:Scopolamine; D006024:Glycopyrrolate