Measurement apparatus, measurement method, and non-transitory storage medium

A measurement method of a measurement apparatus comprising a first biometric sensor, a second biometric sensor, a memory, and at least one processor configured to execute processes, the processes comprising:

• measuring, as a biological signal by the first biometric sensor, at least one of a brain wave signal and a pulse wave signal of a living body;
• measuring, by the second biometric sensor, a respiratory rate of the living body per unit time;
• calculating a differential value of a periodic feature of the biological signal;
• analyzing an activity level of an autonomic nerve of the living body based on the differential value of the periodic feature of the biological signal;
• and
• correcting the activity level of the autonomic nerve of the living body by eliminating a component that is caused by respiration of the living body and that is included in the activity level of the autonomic nerve of the living body based on the respiratory rate of the living body per unit time,
• wherein the correcting further comprises correcting the activity level of the autonomic nerve of the living body by using the respiratory rate of the living body per unit time and a respiratory rate in a steady state.

A non-transitory storage medium that stores a program for a measurement apparatus comprising a first biometric sensor, a second biometric sensor, a memory, and at least one processor, the program, when executed by the at least one processor, facilitates performance of operations comprising:

• measuring, as a biological signal, at least one of a brain wave signal and a pulse wave signal of a living body;
• measuring a respiratory rate of the living body per unit time;
• calculating a differential value of a periodic feature of the biological signal;
• analyzing an activity level of an autonomic nerve of the living body based on the differential value of the periodic feature of the biological signal;
• and
• correcting the activity level of the autonomic nerve of the living body by eliminating a component that is caused by respiration of the living body and that is included in the activity level of the autonomic nerve of the living body based on the respiratory rate of the living body per unit time,
• wherein the correcting further comprises correcting the activity level of the autonomic nerve of the living body by using the respiratory rate of the living body per unit time and a respiratory rate in a steady state.