S8-2. Prefrontal brain activity evaluated by using quantitative time-resolved near infrared spectroscopy during working memory task

Working memory (WM) is a system for actively maintaining and manipulating information, and forms an integral part of the human memory system. Extensive data on human and non-human primates have suggested that the lateral prefrontal cortex (LPFC) plays a central role in WM. On the other side it has long been believed that the daily use of cosmetics improve decrement of cognitive function. However, the neural correlates of improved cognitive performance associated with treatment of such cosmetics are unclear. In the present study, employing quantitative time-resolved near infrared spectroscopy (TRS), we measured cerebral blood oxygenation in LPFC at baseline and during Stanberg’s test (ST) as a WM task, and compared the results with task performance. And using the same ST measurement, we examined how everyday use of cosmetics could affect neuronal activities at the prefrontal cortices for improving working memory performance of healthy female subjects in their forties.