Masaaki Tagawa1, Michiko Kano1, Nobuyuki Okamura2,
Masatoshi Itoh2, Eiko Sakurai1,
Takehiko Watanabe1 and Kazuhiko Yanai1,*
1Department╩of Pharmacology, Tohoku University School of Medicine, 2-1 Seiryo-cho, Aoba-ku, Sendai 980-8575, Japan
2Division╩of Nuclear Medicine, Cyclotron and Radioisotope Center, Tohoku University,
Aramaki Azaaoba, Aoba-ku, Sendai 980-8578, Japan
*╩To whom correspondence should be addressed.
Abstract: Ethanol is a social drug and has been generally known to be a CNS depressant. A large fluctuation of blood alcohol concentration (BAC) is well-known to occur due to main factors such as the genetic polymorphism of the main alcohol metabolizing enzymes and the effect of blood. Few studies have substantially discussed the relationship between impaired CNS activities and BAC. In this study, focusing on the correlation of BAC, we investigated the acute effects of alcohol intake on cognitive performance in humans by objective evaluation methods consisting of the attention-demanding cognitive tasks. Tasks were administered to ten healthy male volunteers before and after ingesting established amounts of alcohol. With increased BAC, we observed prolongation of reaction time performances and lowering of a coordination performance. From the results, we concluded that cognitive performance deteriorates with an increase of BAC. Additionally, the BAC threshold that causes significant impairment of cognitive performance was estimated to be approximately 50╩mg/dl (ca. 10╩mM).
Keywords: Alcohol, Ethanol, Blood alcohol concentration, Cognition, Coordination