Effects of modafinil on performance of radar troops during night shift

Abstract

Objective To investigate the effects of taking modafinil on performance of servicemen in radar troops during night shift. Methods Twenty servicemen in radar troops were served as subjects. They were randomly divided into modafinil and placebo groups(n= 10). 200 mg of modafinil or placebo was orally administered at 2:00 in night shift(0:00～8:00) respectively. Before and after night shift the following parameters were measured: performance of computer simulated radar signal pursuing tasks,critical flicker fusion frequency(CFF), performance of crossing out test. The electrocardiogram and heart rate were continually recorded during the night shift. Results CFF values of post-duty (29.64±1.46) were significantly decreased when compared with those of pre-duty (30.94±1.88) in placebo group(t=5.87, P<0.01). In modafinil group, CFF values (31.65±1.49) and total amount of crossing out (100.50±12.57) of post-duty were significantly higher than those of pre-duty (t= 5.94, 14. 54, P<0. 05). Compared with the placebo group, total amount of crossing out and CFF values of post-duty in modafinil group were significantly increased (t = 2.70, 2.73, P 0. 05). Compared with the placebo group, heart rate, low frequency normalized and low frequency power/high frequency power were increased; but LF, HF, high frequency normalized and total power were decreased, especially root mean squared successive difference and very low frequency power were remarkably decreased in modafinil group (t = 2.41, 2.37, P < 0.05) during the night shift. Conclusions Modafinil orally taking at routine dose could significantly enhance the performance and anti-fatigue abilities of servicemen in radar troops during night shift. Key words: Central nervous system stimulants; Work capacity evaluation; Sleep deprivation; Fatigue; Modafinil; Radar troops