[Effects of local vibration exposure on the cerebral blood flow--on the relation of brain and finger blood flow to vibration frequencies (author's transl)].

The healthy young men aged from 18 to 26 years were examined whether some vibrational stimuli may affect the vasoreaction in the brain and in a finger. The vasoreaction was observed on each subject after the exposure to vibration of frequencies 32, 64, 140 and 250 Hz with acceleration level at 98 m/sec2 and compression force at the vibrating grip of 5 kg, while in the control state the vibration was exactly the same except the vibrational stimuli. Vasodilation and vasoconstriction were observed when low frequency and high frequency vibrational stimuli were given respectively. Vasoreactive pattern of the brain was almost the same as that of the finger.