The covariance between blood and brain alcohol levels and subjective reports of mood were examined in 6 healthy adult men after consumption of 0.7 g/kg of beverage alcohol. There was significant (p less than 0.01) temporal concordance between ascending and peak blood alcohol levels and regional brain alcohol levels as measured by in vivo proton Magnetic Resonance Spectroscopy (MRS) when N-acetyl aspartate (N-AA) concentration was used as an internal standard. The frequency of reports of both euphoria and dysphoria also paralleled the ascending limb of the blood and brain alcohol curve. However, peak blood alcohol levels were higher (125.67 +/- 10.91 mg/dl) and earlier (35 min postdrinking) than peak brain alcohol levels (26.25 +/- 6.38 mg/dl) detected 50 min after alcohol intake. This difference in brain and blood alcohol levels appears to be associated with the echo time (TE) parameters of the MRS. A decrease in TE from 270 msec to 50 msec resulted in a marked increase in brain alcohol detectability. MRS measures will permit analysis of regional differences in brain alcohol concentrations and covariance with behavioral, neurophysiologic and neuroendocrine concomitants of acute alcohol intoxication in man.