Multiple Choice, Multiple Answers

Read the passage and select ALL statements it supports.

Sleep researchers have found that short daytime naps can improve alertness and memory, but the benefits depend heavily on timing and length. A brief nap of about twenty minutes allows the brain to rest without entering deep sleep, so the napper wakes feeling refreshed. Longer naps, however, often push the body into deep sleep stages; waking from these can leave a person groggy and disoriented for a while, a state sometimes called sleep inertia. Experts also advise against napping late in the afternoon, since this can interfere with the ability to fall asleep at night and disturb the regular sleep cycle the following day.