This study examined the sex difference in cognitive aging for verbal abilities. To examine developmental changes on Letter Fluency (LFT) and Semantic Fluency (SFT) tests, healthy 224 women and 139 men over 40 years old participated in this study. The results showed that performance of both sex in the 40's and 50's remained at the same level, but the performance declining for the LFT and the SFT after the 70's were not parallel. For the LFT, men showed a steep decline from 50's to 70's, whereas women showed a gradual decline from 50's to 80's. For the SFT, men showed a sharp decline from 50's to 70's and remained at a similar level after the 70's, whereas women did not show a steep performance decline from their 50's to 70's and their performance level in 70's was the same as in 80's.

The relation between prefrontal cortex and postural functions was examined in relation to developmental changes among healthy middle and upper-middle aged people were examined. The 365 participants of four age groups (40's, 50's, 60's, 70's and 80's; 226 women and 139 men) were given digit cancellation test (D-CAT) for prefrontal cortex related function assessment and the stabilometer measurements for postural functions. The results showed that developmental changes in performances for postural and prefrontal cortex related cognitive function were not parallel. Based upon these findings, characteristics of the developmental changes of cerebro-cerebellar systems in middle and upper-middle aged people were discussed.