THE EFFECTS OF CIGARETTE-SMOKING ON LATE NIGHT PERFORMANCE

This study was undertaken in order to determine the effects of an occa sional late night on both smokers and nonsmokers. Sixteen smokers and 16 non-smokers aged 24-45 years were enrolled onto the study. Full tes t batteries (comprising of Critical Flicker Fusion, CFF; Choice Reacti on Time, CRT; Sternberg Short-Term Memory Task, STM; Compensatory Trac king Task, CTT; and Line Analogue Rating Scales, LARS) were completed at 18.00 h, 22.00 h, 00.00 h, 02.00 h and 08.15 h in the morning. Subj ects were put to bed at 02.30 h and awakened at 07.55 h. Smokers were permitted to smoke freely throughout the trial period. CFF thresholds for the smokers remained almost constant throughout the evening, whils t those from the non-smoking control group dropped significantly from baseline (p < 0.0001). The CRT test showed that for both RRT and TRT p erformance remained almost constant for the non-smoking group compared with baseline, whilst the smokers' RRT improved significantly (p < 0. 05) over time. TRT was quicker throughout for the smokers relative to baseline, but this did not reach significance. Performance on the MRT component was significantly quicker than baseline for the smokers at 2 2.00 h and 02.00 h. The RT element of the CTT task was impaired throug hout the night for both groups but performance was notably better for the smoking group. Tracking error was comparable. STM gradually improv ed from baseline in both groups, to st greater extent in the smokers. There was a significant effect of time from the LARS data (p < 0.001) as both groups followed the pattern of the other with regards to subje ctive tiredness, alertness and drowsiness. When people are required to perform tasks in the late night and early morning smokers show no dec rement, whilst the performance of non-smokers gets worse. (C) 1997 by John Wiley & Sons, Ltd.