Self-reported sleepiness, alertness, and attentiveness
sleepiness
There was no difference in self-reported sleepiness measured by KSS scores, PANAS alertness, and PANAS attentiveness ratings at the pre-nap baseline between nap conditions (Post-nap test performance relative to pre-nap between the wake group and each nap condition was measured at 5 min, 30 min, 60 min, and 240 min intervals. Error bands represent standard errors.*For the alertness measure on the PANAS, relative to wake, the 30 min, and 60 min naps led to significant increases in alertness scores emerging at 30 min and 60 min post-nap respectively that were sustained up to 240 min post-nap. Increases in alertness scores were not seen for the 10 min nap.On the PANAS attentiveness scale, compared to wake, naps of all lengths increased attentiveness scores. For the 10 min nap, this was seen at 60 min post-nap. For the 30 min and 60 min naps, significant increases in attentiveness were seen from 30 min post-nap and lasted up to 60 min post-nap for the 30 min nap, and up to 240 min post-nap for the 60 min nap.