Lizzie McDevitt (UC Riverside)
To nap or not to nap: The effect of nap frequency on daytime sleep architecture

Napping has been shown to alleviate the negative physical and psychological symptoms of disrupted sleep, as well as improve performance across a range of memory tasks. Despite the demonstrated benefits of napping, the question remains as to why some people nap and others do not. My research examines daytime sleep architecture differences between habitual and non-habitual nappers. Sleep-wake patterns were monitored for one week with actigraphy followed by a 75-minute polysomnography-recorded nap. We found that greater nap frequency was correlated with increased Stage 1 (light sleep) and decreased slow wave sleep (deep sleep). We categorized subjects based on nap frequency during the prior week (0 naps, 1 to 2 naps, and 3 to 4 naps) and found differences in Stage 1, Stage 2, and slow wave sleep (SWS) between groups. Subjects who took 0 naps had the greatest amount of SWS, those who took 1 to 2 naps had the most Stage 2 sleep, and those who took 3 to 4 naps had the most Stage 1. These systematic differences in sleep architecture may influence nap behavior and changes in performance following a nap. To this end, I will also present some preliminary data that indicate habitual nappers may show more perceptual learning benefits than non-habitual nappers.