Behrens T, et al. - Female shift workers of the Bergmannsheil University Hospital in Bochum, Germany (N=74; 94% nurses), were examined after day and night shifts for psychomotor vigilance in this study. At the end of 2 consecutive day shifts and at the end of 3 consecutive night shifts, a 3-minute Psychomotor Vigilance Task (PVT) test bout was undertaken by the participants. Researchers analyzed psychomotor vigilance in terms of mean reaction time, percentage of lapses and false starts, and throughput as an overall performance score, combining reaction time and error frequencies. Results suggested an association of night-shift work with decreased psychomotor vigilance, supporting the growing body of literature on this topic. The analysis of reaction time coefficient of variation suggested that fewer slow reactions at the lower end of the reaction time distribution function may selectively influence the performance deficits. Comparison of intra-individual PVT-performances over 3 consecutive night and 2 consecutive day shifts revealed improvement in the performance following the third night shift. This finding indicated that avoiding fast-changing shift schedules may lead to a better adjustment to the night schedule; however, a training effect cannot be ruled out.