Psychomotor and visual performance under the time-course effect of alcohol.

This study examined reaction time (RT), anticipation time (AT), and visual performance under the influence of blood alcohol concentration (BAC), using a repeated-measures design. Subjects (8 men and 8 women), 21 to 40 yr. of age, participated in both single- and double-dose sessions, in which they drank approximately 2.3 oz. and 4.6 oz. of 86-proof vodka, respectively. The breath BAC was measured at 5-min. intervals. The RT, AT, and visual performance were tested every 20 min. for 140 min. in both sessions. In general, results indicated that RT, AT, and stereoscopic vision were impaired more in the rising BAC curve than the falling BAC curve. In addition, the impairment tended to be greater for the double-dose than the single-dose session. The far and near visual acuities were not affected by the BAC.