Written By: Debjani Arora | Updated : October 8, 2018 2:24 PM IST
A 90 minute power nap can help one get better at decision making, says study. © Shutterstock
Lack of sleep can lead to a lot of health issues both physiological and psychological. But if you are lucky enough to get some power nap throughout the day you still stand a fair chance to avoid the detrimental effects of less sleep. Feeling sleepy or groggy in the morning, especially if you have not slept well at night is going to affect you in a number of ways it can hamper productivity, perception and also decision-making abilities. According to a study published in the Journal of Sleep Research, a well-timed nap could prevent the decision-making mind from getting led astray by subconscious influences. Just a simple nap can help to improve the symptoms of being tired.
Led by Liz Coulthard, Ph.D., a senior lecturer who studies cognitive neuroscience, and research associate Netasha Shaikh, Ph.D., both at the University of Bristol's Medical School in the United Kingdom, this trial investigated the effects of a 90-minute nap (quite a long one) on the ability of people to sort through the subconscious factors that influence their decisions.
In the study, 16 volunteers took 90-minute naps enough to equate to a full sleep cycle before completing a series of tricky association tests meant to test the brain's decision-making in deliberately confounding circumstances. In real life, subconscious factors like hunger can lead to impulsive decision making; in this test, the researchers used words to subconsciously complicate the decision-making process.
This trial was designed to make it difficult for participants to make the right decision so the team could observe how sleep affected that process. Participants were told to simply identify a word that flashed on the screen as a negative or positive word. Of course, it wasn't as simple as that. Right before they saw the main word, a different positive or negative word flashed for 33 milliseconds so briefly that it would be impossible to consciously register what that word was but long enough for the subconscious to pick up on it. This was the "unconscious prime."
As you might expect, earlier studies have shown that seeing an unconscious prime that's congruent with the main word (for example, "peace" followed by "happy," both positive words) makes it easier to categorize the main word. But in non-congruent word pairs, it's much trickier to identify the second word, regardless of how sleep deprived you might be.
Nevertheless, the 16 volunteers who performed the test immediately after a 90-minute nap placed words into their correct categories faster indicating that the task was easier than it had been before they retreated to their beds in the lab. The average time for participants to identify the words incongruent pairs dropped from over 670 milliseconds before napping to just over 610 milliseconds after napping. It's a small difference, but the researchers think it can be chalked up to what's going on beneath the surface.
