Power nap enhances cognitive performance: AIIMS-Patna study

In the pilot study, all the participants, divided into two groups, were given a standard set of Sudoku, a number game based upon logical thinking, with graded difficulty levels

A study at Patna’s All India Institute of Medical Sciences (AIIMS) has found that a power nap during the day enhances human cognitive performance, especially calculative ability or execution of skilful tasks like driving, etc.

Usually nap has got a negative psycho-social stigma and is unacceptable in most of the circumstances, especially at work places, said an expert. (Shutterstock)

The pilot study conducted on 68 healthy male and female volunteers in the 18 to 24 years age group found that those who took a short nap performed significantly better in solving problems and completing the task in comparison to those in wakeful rest period.

“Both slow wave sleep, also referred to as deep sleep, as well as rapid eye movement (REM) sleep, a stage when a person dreams in sleep, during the day time nap has shown significant impact upon the uncompleted numerical logical tasks, suggesting the nap being a useful behaviour for cognitive enhancement,” said Dr Kamlesh Jha, a co-author and additional professor, department of physiology at AIIMS-Patna.

The scientific report co-authored by Dr Ramji Singh, the then professor of physiology and currently the director of AIIMS-Kalyani in West Bengal, Dr Yogesh Kumar, additional professor, and Dr Abhilasha Mishra, senior resident in the department of physiology at AIIMS-Patna, has been published as an original research paper in the International Journal of Scientific Research, in September 2019.

“This is a mid-term outcome. We want to continue with our study and will request for government funds for research. We will like to broaden the scope of study by including more volunteers so that we get a robust outcome,” said Dr Jha.

In the pilot study, all the participants, divided into two groups, were given a standard set of Sudoku, a number game based upon logical thinking, with graded difficulty levels. Each group participants were given 10-12 minutes for each level. When they got stuck at a certain level of difficulty, the test group was allowed to take a nap whereas the other group was allowed to take wakeful rest.

After spontaneous awakening or wakeful rest for one hour, the participants were given the same set of Sudoku at the same level where they got stuck earlier and responses were checked whether the particular level has been completed successfully or not.

“In the control group participants, who stayed awake, out of 37, only six were able to solve the given Sudoku task while 31 could not. In the test group participants, who slept, out of 31, as many as 16 accomplished the task, while 15 could not,” said Dr Jha.

“On further comparison of solvers and non-solvers from the control group that stayed awake with that of slow wave sleep group, which went in deep sleep, 13 out of 18 participants, who attained deep sleep, could complete the task successfully while five of them could not,” he added.

When a comparison was made between those who stayed awake to those who attained rapid eye movement (REM) sleep,13 were able to complete the Sudoku task successfully whereas 12 could not finish the task.

Summing up the study, Dr Jha said, “Usually nap has got a negative psycho-social stigma and is unacceptable in most of the circumstances, especially at work places. Our study has attempted to throw some light over its potential usefulness in the cognitive task performance enhancement. Further study with bigger data base could be more conclusive.”