Perception of relevant information by an operator is accompanied by hi
s skin resistance response (SRR). By experiment a threshold of the SRR
interimpulse interval was found, at the excess of which an operator's
functional state is interpreted as ''loss of vigilance''. Using this
knowledge an algorithm has been developed for control (self-regulation
) of a ''man-machine'' system operator's vigilance level during the ex
ecution of activity, and based on a method using visual and sound biof
eedback from the SRR interimpulse interval parameters. Depending on th
e current values of the SRR interimpulse interval static or dynamic vi
sual biofeedback is used When the SRR interimpulse interval exceeds th
e threshold value, dynamic visual and sound biofeedback are simultaneo
usly used. Simultaneously it is a command to the operator to execute t
he test algorithm with a limited execution time. If this algorithm has
not been executed, or has been executed with an error, or if some pre
-set time is exceeded, the ''man-machine'' system is switched to the e
mergency operating mode.