 In order to evaluate the psychological fitness, the working memory was assessed using computerized battery test while the attention and cognitive processing were assessed via event related potential. Emotion was assessed via Bond-Läder test whereas psychological symptoms were evaluated by symptoms checklist-90 SCL-90. In addition, the functions of cholinergic and monoaminergic system especially dopamine were also evaluated using the activities of acetylcholinesterase AChE, monoamine oxidase MAO B as indices respectively. The assessments were performed at the same time schedules as the physical assessment. The results showed that the subjects who consumed cashew apple juice based drink at dose of 240 mgday showed the following changes; 1 working memory was improves in all domains including the increased power of attention, the increase continuity of attention, the speed of memory and the quality of memory 2 the decreased latency but increased amplitude of N100 and P300 3 the suppression of AChE and MAO-B. Therefore, the current data revealed that the volunteers who consumed the cashew apple juice based drink at dose of 240 mgday enhance attention and cognitive processing ability giving rise to the improved working memory. The possible underlying mechanism might occur partly via the improved cholinergic and dopaminergic functions. 