Abstract
Falling accidents can occur when individuals suddenly stand up from a sitting position. Rapid orthostatic hypotension can occur and impair the blood supply to the brain. We tried to verify whether“prior notice”affect the change in blood pressure. This study investigated the effects of anticipatory control on changes in the circulatory system. Eight healthy adults（mean age, 21.5 years; range, 19-23 years, 163±2 cm, 58±4 kg）were asked to stand up with or without prior notification from chairs of two different heights（20 or 40 cm）. Electroencephalography and cerebral circulation were monitored continuously, and blood pressure was compared before and after standing. Though no statistically significant differences were observed for individual indices of heart rate, blood pressure, and cerebral blood flow between the presence and absence of prior notice, a significant difference was found for sympathetic nerve activity which can be expected to buffer any rapid changes in hemodynamics. In addition, the effects of chair height had a remarkable impact in this study. The 20-cm chair height significantly caused a larger load on hemodynamics than the 40-cm height. In conclusion, sitting-standing position in daily living space is thought to be important for any people, and anticipatory control may be help for avoiding orthostatic hypotension in clinical settings.
