title: Methadone restores local and remote EEG functional connectivity in opioid-dependent patients.
abstract: Currently it has been proposed that normal brain function is critically dependent upon a dynamical balance between functions of local neuronal assemblies and global integrative processes. A loss of such metastable balance in favor of either independent or hyper-ordered processing is considered as the reflection of a brain disease. It has been shown that opioid dependence can be characterized as a disease of brain metastable balance, wherein local functional connectivity (synchronicity within neuronal assemblies) increased and remote functional connectivity (synchronicity between neuronal assemblies) decreased. Since methadone may be used as a maintenance treatment for opioid-dependent patients, the aim of this research was to study how methadone would influence the temporal and metastable cortical organization through the measures of local and remote electroencephalogram (EEG) functional connectivity in six opioid-depended patients who manage to complete at least six-month methadone treatment. The present study demonstrated that average parameters of temporal and metastable organization of the cortical dynamics (indexed by local and remote EEG functional connectivity) in such opioid-dependent patients did not differ from normal values of healthy subjects. We interpret these findings as a capability of the methadone to restore a normal temporal and metastable structure of brain activity in opioid-dependent patients after many months of methadone treatment. To our knowledge, present preliminary study is the first where the influence of methadone on temporal and metastable structure of EEG activity is demonstrated.
authors.affiliation: BM-SCIENCE-Brain and Mind Technologies Research Centre, Espoo, Finland. Andrew.Fingelkurts@bm-science.com
authors.forename: Andrew A
authors.initials: AA
authors.lastname: Fingelkurts
authors.forename: Alexander A
authors.initials: AA
authors.lastname: Fingelkurts
authors.forename: Reetta
authors.initials: R
authors.lastname: Kivisaari
authors.forename: Taina
authors.initials: T
authors.lastname: Autti
authors.forename: Sergei
authors.initials: S
authors.lastname: Borisov
authors.forename: Varpu
authors.initials: V
authors.lastname: Puuskari
authors.forename: Olga
authors.initials: O
authors.lastname: Jokela
authors.forename: Seppo
authors.initials: S
authors.lastname: Kähkönen
mesh_terms: D000328:Adult; D000513:Alpha Rhythm / Q000187:drug effects; D001611:Beta Rhythm / Q000187:drug effects; D003627:Data Interpretation, Statistical; D004569:Electroencephalography / Q000187:drug effects*; D005260:Female; D006556:Heroin Dependence / Q000503:physiopathology / Q000534:rehabilitation; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008691:Methadone / Q000494:pharmacology* / Q000627:therapeutic use; D009294:Narcotics / Q000494:pharmacology* / Q000627:therapeutic use; D009434:Neural Pathways / Q000187:drug effects*; D009293:Opioid-Related Disorders / Q000503:physiopathology* / Q000534:rehabilitation; D011569:Psychiatric Status Rating Scales
chemical_list: D009294:Narcotics; D008691:Methadone