The Effects of Cigarette Smoking on Late Night Performance

Abstract

This study was undertaken in order to determine the effects of an occasional late night on both smokers and non-smokers. Sixteen smokers and 16 non-smokers aged 24–45 years were enrolled onto the study. Full test batteries (comprising of Critical Flicker Fusion, CFF; Choice Reaction Time, CRT; Sternberg Short-Term Memory Task, STM; Compensatory Tracking 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. Subjects 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, whilst those from the non-smoking control group dropped significantly from baseline (p < 0·0001). The CRT test showed that for both RRT and TRT performance 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 22.00 h and 02.00 h. The RT element of the CTT task was impaired throughout the night for both groups but performance was notably better for the smoking group. Tracking error was comparable. STM gradually improved from baseline in both groups, to a 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 subjective tiredness, alertness and drowsiness. When people are required to perform tasks in the late night and early morning smokers show no decrement, whilst the performance of non-smokers gets worse. © 1997 John Wiley & Sons, Ltd.