Aims: 

The prediction of the performance of human operator of machine systems can be done by the monitoring of individual differences in the changes of physiological parameters.

Methods: 

In the population of 40 young male subjects the measurements of skin potential level (SPL) in palmar area as an index of autonomic sympathetic arousal and short term memory test (recalling of listened in a series of 12 random 2 digit numbers) were conducted 5 times per day (on 9, 12, 15, 18, 21 h.) during 5 days.

Results: 

It was shown that circadian changes of SPL can be considered as a trait – like property, because the pattern of the changes was stable in every subject during all 5 days of observation. In the groups of subjects with maximal SPL in the morning or in the evening the ratings of short term memory were lower (68.7 ± 4.3 and 61.2 ± 4.5) than in the group with random fluctuations, absent circadian structure of SPL (81.1 ± 5.5, p < 0.05 by t – test). The best rating of short term memory was observed in a subject in the time of individually highest SPL.

Conclusion: 

Both current skin potential level and its circadian changes are good predictors of human operator performance.