[Changes in different human physiologic indices during the processing of growing volumes of visual information]

The paper deals with correlations of EEG, EMG, EGG, pneumogramme parameters of human operator, as well as of the intensity and efficiency parameters of his activity, with the degree of mental load, determined by the speed of presentation of visual signals. A physiological criterion has been elaborated of the difficulty of operator's activity in processing of increasing visual information, i. e. the level of behavioural activity. This criterion revealed unidirected changes with an increase of mental load, and showed close connections with the speed of signals' presentation, number of errors and of motor responses during successful task performance.