Having only 6.5 hours to sleep in 24 hours degrades performance and mood, finds a new study in teens. However, students in the split sleep group (night sleep of 5 hours plus a 1.5-hour afternoon nap) exhibited better alertness, working memory and mood than those who slept 6.5 hours continuously.

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Having only 6.5 hours to sleep in 24 hours degrades performance and mood, finds a new study in teens. However, students in the split sleep group (night sleep of 5 hours plus a 1.5-hour afternoon nap) exhibited better alertness, working memory and mood than those who slept 6.5 hours continuously.