0058 The sleepy eyewitness: Self-reported sleep predicts eyewitness memory

Abstract

Abstract Introduction Sleep is critical for memory, but research indicates that eyewitness identification may be an exception. We conducted three experiments to assess the effect of self-reported sleep duration and quality, and current sleepiness on eyewitness recall for a mock crime and suspect identification. Experiments 1 and 2 looked at pre-encoding sleep on lineups and showups, respectively. Experiment 3 investigated lineups across two days to assess retrieval effects. Methods Participants viewed a mock crime video then answered sleep questions as well as central and peripheral recall questions over the crime. Participants were then randomly assigned to view a fair 6-person target-present (TP) or target-absent (TA) lineup for experiments 1 and 3, or a TP or TA showup for experiment 2. In experiment 3, the recall questions and lineups occurred on day 2, but the sleep questions were asked both days. Decision confidence was provided after the identification procedure. Results Sleep quality predicted central recall for experiment 1 [F(1, 3834)=12.96, p<.001] whereas sleep quantity predicted central recall for experiment 2, F(1, 2712)=36.22, p< .001. Choosing rate for pre-encoding sleep was higher for low quality [X2(1)=29.10, p<.001] and low duration [X2(1)=20.15, p<.001], but false IDs were lower for high duration [X2(1)=29.76, p<.001] and high quality, X2(1)=35.47, p<.001. High quality self-reported sleep increased discriminability for lineups, G=2.14, p=.016. False IDs for showups were lower for high duration [X2(1)=5.27, p=.024] and all three sleep questions predicted discriminability for showups: more sleep (G=2.85, p=.002), better sleep (G=2.60, p=.005), and less sleepiness, G=2.44, p=.007. Showups had greater accuracy (p=.038) and a stronger confidence-accuracy relationship (p<.001) for the average of the “good sleep” conditions than the average of the three “bad sleep” conditions, p=.022. In experiment 3, involving post-encoding self-reported sleep, there were still effects on recall but minimal effects on eyewitness identification (and no effects on discriminability). Conclusion Self-reported sleep for the night prior to the crime could be an important individual difference variable for eyewitness memory, affecting encoding more than post-encoding processes. Support (if any) This project was supported by Grant 2018-R2-CX-0027 awarded by the National Institute of Justice, Office of Justice Programs, and U.S. Department of Justice.