Patent ID: 7413548

Claim:
An autonomic nervous activity monitoring method for predicting whether abnormal reaction may occur to a body, comprising the steps of: measuring heartbeat or pulse of a body to acquire a pattern of the heartbeat or pulse as biological information; calculating a value [msec 2 ] of a high frequency component (a HF value) defined as an indicator for parasympathetic activity and a value of a ratio of a low frequency component (LF) to the high frequency component (a LF/HF ratio value) defined as an indicator for sympathetic activity on a time-series base by carrying out frequency analysis to the acquired pattern of the heartbeat or pulse; and predicting whether abnormal reaction may occur to the body from a predetermined relationship between the HF value and the LF/HF ratio value, based upon the calculated HF values and the calculated LF/HF ratio values; wherein, when alpha is defined as a predetermined coefficient, the predicting step predicts that abnormal reaction may occur to the body when the calculated HF value exceeds a predetermined reference value, and, when a sum of a period of {(the calculated HF value)>(the coefficient alpha)×(the calculated LF/HF ratio value)} becomes not less than 10% of a calculation period in the calculating step.