MEDIUM-TERM PREDICTION OF THE SPEED OF SIMPLE OCULAR-MOTOR REACTION BY VALUES OF BLOOD PRESSURE AND HEART RATE VARIABILITY

One of the symptoms of asthenia in space flight is a decrement of cognitive efficiency, memory and concentration. A demand exists for simple noninvasive methods to forecast appearance of cognitive shifts. It is hypothesized that blood pressure (BP) and heart rate variability (HRV) measured in the morning can predict the psychomotor reactions as at the time of measurement, so in the course of the day (medium-term prediction). The investigation involved 6 volunteers (29-44 y.o.) for a 120-day isolation study. The protocol included 5-min ECG and BP measurement soon after awakening, and HRV evaluation. The classic simple ocular-motor reaction (SOMR) test was performed before and then after midday. Regression analysis of reaction duration and stability showed that SOMR time correlated with the homeostatic parameters (BP, HR); stability of SOCM duration correlated both BP and HR, and parameters reflecting HR regulation processes. Elevated diastolic BP correlated with an increase of reaction duration irrespective of whether the test was performed before or in midday. Elevation of diastolic BP and autonomic balance shift toward the sympathetic activity in the morning correlated with a loss in SOMR stability no matter when the test was performed.