Effects of cosmetic therapy on cognitive function in elderly women evaluated by time-resolved spectroscopy study

Abstract

With the rapid increase in dementia in developed countries, it is important to establish methods for maintaining or improving cognitive function in elderly people. To resolve such problems, we have been developing a cosmetic therapy (CT) program for elderly women. However, the mechanism and limitations of CT are not yet clear. In order to clarify these issues, we employed time-resolved spectroscopy (TRS) to evaluate the effect of CT on prefrontal cortex (PFC) activity in elderly females with various levels of cognitive impairment. Based on the Mini- Mental State Examination (MMSE) score, the subjects were classified into mild (mean MMSE score: 24.1±3.8) and moderate (mean MMSE score: 10.3±5.8) cognitive impairment (CI) groups (p<0.0001). The mild CI group exhibited significantly larger baseline concentrations of oxy-Hb and t-Hb than the moderate CI group. CT significantly increased the baseline concentrations of oxy-Hb (p<0.002) and t-Hb (p<0.0013) in the left PFC in the mild CI group. In contrast, CT did not change the concentrations of oxy-Hb and t-Hb in the moderate CI group (p>0.05). These results suggest that CT affects cognitive function by altering PFC activity in elderly women with mild CI, but not moderate CI.