title: Heavy alcohol use in adolescence is associated with altered cortical activity: a combined TMS-EEG study.
abstract: Long-term alcohol use affects cognitive and neurophysiological functioning as well as structural brain development. Combining simultaneous electroencephalogram (EEG) recording with transcranial magnetic stimulation (TMS) enables direct, in vivo exploration of cortical excitability and assessment of effective and functional connectivity. In the central nervous system, the effects of alcohol are particularly mediated by alterations in gamma-aminobutyric acid (GABA)ergic neurotransmission, and TMS-evoked potentials (TEPs) N45 and N100 in EEG are known to reflect GABAergic function. However, no previous studies have examined the effects of long-term alcohol use in adolescence on TEPs. In this study, a total of 27 young adults with heavy alcohol use in adolescence and 25 age-matched, gender-matched and education-matched controls with little or no alcohol use participated in TMS-EEG measurements. The motor cortex (M1) was stimulated with an intensity of 90 percent of the resting motor threshold of the abductor pollicis brevis muscle. No significant differences were found in the resting motor threshold, TEP latencies or neuropsychological functioning between the groups. We observed an increase in the global mean field power in the time window of 54- to 75-millisecond post-TMS, as well as significant topographical differences in the P60 and N100 in those with a history of heavy drinking. Furthermore, there was a marked increase in the GABAergic N45 amplitude in alcohol users. These findings suggest that long-term alcohol use in adolescence, even when not meeting the diagnostic criteria for a disorder, is associated with changes in connectivity and cortical excitability.
authors.affiliation: Department of Adolescent Psychiatry, Kuopio University Hospital, Kuopio, Finland.|Doctoral Programme of Clinical Research, School of Medicine, University of Eastern Finland, Kuopio, Finland.
authors.forename: Outi
authors.initials: O
authors.lastname: Kaarre
authors.affiliation: Department of Applied Physics, University of Eastern Finland, Kuopio, Finland.|Department of Clinical Neurophysiology, Kuopio University Hospital, Kuopio, Finland.
authors.forename: Elisa
authors.initials: E
authors.lastname: Kallioniemi
authors.affiliation: Department of Clinical Neurophysiology, Kuopio University Hospital, Kuopio, Finland.|Department of Clinical Radiology, Kuopio University Hospital, Kuopio, Finland.
authors.forename: Mervi
authors.initials: M
authors.lastname: Könönen
authors.affiliation: Department of Adolescent Psychiatry, Kuopio University Hospital, Kuopio, Finland.|Department of Psychiatry, School of Medicine, University of Eastern Finland, Kuopio, Finland.
authors.forename: Tommi
authors.initials: T
authors.lastname: Tolmunen
authors.affiliation: Department of Adolescent Psychiatry, Kuopio University Hospital, Kuopio, Finland.
authors.forename: Virve
authors.initials: V
authors.lastname: Kekkonen
authors.affiliation: Doctoral Programme of Clinical Research, School of Medicine, University of Eastern Finland, Kuopio, Finland.
authors.forename: Petri
authors.initials: P
authors.lastname: Kivimäki
authors.affiliation: Doctoral Programme of Clinical Research, School of Medicine, University of Eastern Finland, Kuopio, Finland.
authors.forename: Noora
authors.initials: N
authors.lastname: Heikkinen
authors.affiliation: Department of Neurology, University Campus Biomedico, Rome, Italy.
authors.forename: Florinda
authors.initials: F
authors.lastname: Ferreri
authors.affiliation: Department of Adolescent Psychiatry, Kuopio University Hospital, Kuopio, Finland.|Department of Psychiatry, School of Medicine, University of Eastern Finland, Kuopio, Finland.
authors.forename: Eila
authors.initials: E
authors.lastname: Laukkanen
authors.affiliation: Department of Clinical Neurophysiology, Kuopio University Hospital, Kuopio, Finland.|Department of Clinical Neurophysiology, Institute of Clinical Medicine, Faculty of Health, University of Eastern Finland, Kuopio, Finland.
authors.forename: Sara
authors.initials: S
authors.lastname: Määttä
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D002540:Cerebral Cortex / Q000503:physiopathology*; D004569:Electroencephalography; D005071:Evoked Potentials / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D018080:Receptors, GABA-B / Q000378:metabolism / Q000502:physiology; D009435:Synaptic Transmission / Q000502:physiology; D050781:Transcranial Magnetic Stimulation; D000066608:Underage Drinking; D055815:Young Adult; D005680:gamma-Aminobutyric Acid / Q000378:metabolism
chemical_list: D018080:Receptors, GABA-B; D005680:gamma-Aminobutyric Acid
keywords: GABA; TMS-EEG; adolescents; alcohol