Ameliorative effect of traditional Japanese medicine yokukansan on age-related impairments of working memory and reversal learning in rats

▶Yokukansan (YKS) is a traditional Japanese medicine (a kampo drug). ▶YKS did not affect simple discrimination learning. ▶YKS ameliorated age-related working memory impairment. ▶YKS ameliorated age-related reversal learning impairment. ▶Dopamine mechanism in prefrontal cortex might be involved in these ameliorations.