Want to make sure you remember to call your mom on her birthday? Then remind yourself of the task before getting a good night’s sleep. Good sleep improves your brain’s ability to make associations that help you remember to do a task in the future, according to a study published in Psychological Science and reported in a Washington University in St. Louis news release.

Prospective memory includes things we intend to do (as opposed to retrospective memory, things we did in the past). Prospective memory is commonly triggered by particular cues, such as a place, situation or circumstance that helps us recall our to-do list. For example, seeing a picture of your mother will help you remember to call her.

For the study, researchers tested 96 Washington University students. The students were broken into four groups of 24.

Researchers told the students they’d be given three exams and that during the last one, the words “table” and “horse” would appear. Students were instructed to press a button labeled “Q” whenever the words popped up. (The prospective memory task was for students to remember to press the button.)
Researchers made half of the four groups controls. One control group tested in the morning; the other in the evening. The third group prepared for testing in the morning then took the test 12 hours later, in the evening. The fourth group studied the test routine in the evening then hit the sack and tested in the morning, 12 hours later.

Findings showed that students who tested after a good night’s sleep performed the prospective memory task in the last test category better than the other students.

Here’s the tricky part: The sleep didn’t strengthen prospective memory by directly bolstering the memory to perform the task. Instead, sleep helped the brain strengthen weaker associations linked with the task.

In the end, it amounts to the same result: Remember to get your zzz’s.

Read RH’s, “40 (Plus) Winks” to learn how getting more sleep could save your life.