1 Department of Biological and Medical Psychology, University of Bergen, Norway
2 Department of Radiology, Haukeland University Hospital, Bergen, Norway
3 Department of Physics and Technology, University of Bergen, Norway
4 Department of Clinical Engineering, Haukeland University Hospital, Bergen, Norway
5 Division of Psychiatry, Haukeland University Hospital, Bergen, Norway
The aim of this study was to investigate how alcohol intoxication at two blood alcohol concentrations (BAC) affected neuronal activation during increasing levels of cognitive load. For this purpose we used functional magnetic resonance imaging (fMRI) together with a working memory n-back paradigm with three levels of difficulty. Twenty-five healthy male participants were scanned twice on two separate days. Participants in the control group (N=13) were scanned after drinking a soft-drink at both scanning sessions, while participants in the alcohol group (N=12) were scanned once after drinking an alcoholic beverage resulting in a BAC of 0.02%, and once after drinking an alcoholic beverage resulting in a BAC of 0.08%. A decrease in neuronal activation was seen in the dorsal anterior cingulate cortex (dACC) and in the cerebellum in the alcohol group at the BAC of 0.08% when the participants performed the most demanding task. The dACC is important in cognitive control, working memory, response inhibition, decision making and in error monitoring. The results have revealed that the effect of alcohol intoxication on brain activity is dependent on BAC and of cognitive load.
open-access license: This is an open access article licensed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0/) which permits unrestricted, non-commercial use, distribution and reproduction in any medium, provided the work is properly cited.
* Address correspondence to this author at the Department of Biological and Medical Psychology, Jonas Lies vei 91, N-5009 Bergen, Norway; Tel: + 47 55 58 60 84, + 47 41 29 85 17; Fax: + 47 55 58 98 72; E-mail: email@example.comTo control for possible learning effects caused by repeating the working memory task twice (at BACs of 0.02% and 0.08% for participants in the alcohol group), participants in the control group was also scanned twice. The control group which was used in the analysis consisted thus of neuroimaging data obtained in the first scanning session for seven of the participants and of neuroimaging data from the second scanning session for six of the participants.