The effect of 3-(2-benzylmethylaminoethyl) benzoic acid methyl ester hydrochloride (PRL-8-53) on learning and on retention of verbal information in human subjects was investigated. Using the serial anticipation method under double-blind conditions it was found that PRL-8-53 causes slight improvement of acquisition. Retinetion of verbal information was found improved to a statistically significant degree (most P values better than 0.01, some better than 0.001). No significant changes were found for either visual reaction time or motor control after drug when compared with placebo values.