Napping between studies

February 21, 2017
  • Even in well-rested people, naps can improve performance in areas such as reaction time, logical reasoning and symbol recognition, as Cote described in a 2009 review (Journal of Sleep Research, 2009). They can also be good for one’s mood.
  • A study by University of Michigan doctoral student Jennifer Goldschmied and colleagues found that after waking from a 60-minute midday nap, people were less impulsive and had greater tolerance for frustration than people who watched an hour long nature documentary instead of sleeping (Personality and Individual Differences, 2015). “Frustration tolerance is one facet of emotion regulation,” says Goldschmied. “
  • “What’s amazing is that in a 90-minute nap, you can get the same [learning] benefits as an eight-hour sleep period,” Mednick says. “And actually, the nap is having an additive benefit on top of a good night of sleep.”
  • In another experiment, Mednick found that an afternoon nap was about equal to a dose of caffeine for improving perceptual learning. But in other ways, a midday doze might trump your afternoon latte. She found people who napped performed better on a verbal word-recall task an hour after waking compared with people who took caffeine or a placebo (Behavioural Brain Research, 2008). While caffeine enhances alertness and attention, naps boost those abilities in addition to enhancing some forms of memory consolidation, Mednick notes.
  • Other research builds the case that the hippocampus benefits from a nap. Matthew Walker, PhD, a professor of psychology at the University of California, Berkeley, and colleagues recruited volunteers to tax their associative memories by learning a long list of name-face pairings.
  • Half the participants then took 90-minute midday naps. That evening, the participants were given a new round of learning exercises with novel pairings. Those who hadn’t napped didn’t perform as well on the evening test as they had in the morning. But the nappers did better on the later test, suggesting the sleep had boosted their capacity for learning (Current Biology, 2011).
  • According to new research, all we’d really need is a solid 10-minute power nap to boost our focus and productivity.Researchers tested four nap time spans: 5, 10, 20 and 30 minutes (and a control group that didn’t nap).  They then tested participants across several benefits for three hours after the nap.  Here’s a summary of the results:The 5-minute nap produced few benefits in comparison with the no-nap control. The 10-minute nap produced immediate improvements in all outcome measures (including sleep latency, subjective sleepiness, fatigue, vigor, and cognitive performance), with some of these benefits maintained for as long as 155 minutes. The 20-minute nap was associated with improvements emerging 35 minutes after napping and lasting up to 125 minutes after napping. The 30-minute nap produced a period of impaired alertness and performance immediately after napping, indicative of sleep inertia, followed by improvements lasting up to 155 minutes after the nap.