Effect of Pranayama on cognition and other higher mental functions

Year : 2019 | Volume : 7 | Issue : 2 Page : 50-55

Srinivas Ch¹, Padmaja T², Bhagyalakshmi K³

¹Assistant Professor, ²Associate Professor, ³Professor, Department of Physiology, Prathima Institute of Medical Sciences, Nagunur,Karimnagar.

^*Corresponding author: Padmaja T, Associate professor, Department of physiology, Prathima institute of medical sciences, Nagunuru, Telangana state. Cell : 98851367733

Email ID: - kprao2011@yahoo.com

Abstract

Introduction:

Yoga and pranayama are the ancient Indian life style practices which has no limits for age or gender. The main aim of this study is to evaluate the effect of pranayama on cognition.

Materials and methods: This is a pre-post study which includes 100 healthy medical students of 18-25 years age group with equal male to female ratio. They practised daily pranayama (anulom vilom) for 10 minutes; two hours post lunch for 12 weeks in clinical laboratory, department of physiology, Prathima institute of medical sciences. Their cognitive function is assessed by trail making test and mini mental state examination at the beginning and at the end of 12 weeks period in which they regularly practised pranayama, and the results were compared.

Results: There is no significant gender difference in the results obtained. After 12 weeks regular practise of pranayama, there is a significant reduction in the time taken for trail making test (P<0.001) and also significant improvement in the scores of mini mental state examination (P<0.001).

Conclusion: This study shows that, there is a significant improvement of cognition with regular daily practise of pranayama.

INTRODUCTION

Yoga and pranayama are one of the best exercises designed by mankind to improve the health of the human body. Day to day Pranayama helps in improving one’s memory, concentration, attention, sequential learning, eye-hand coordination, calculation ability etc., thereby improving cognitive functions. If continued to practice with discipline throughout the life pranayama may help to combat the impairment of cognition in the elderly people.¹ Pranayama also helps in stress reduction and reduction of anxiety status by mainly checking on the sympathetic over activity along with other lifestyle changes.²

Regular practice of pranayama in those healthy young adult individuals showed significant improvement in rapid fire arithmetic deviation and playing card test scores. Subjects also showed a significant reduction in time taken for letter cancellation test concluding pranayama helps in improving ones cognitive processes. ¹ In human body, both the nostrils (right and left) do not function simultaneously. One nostril will be always more congested than the opposite, even when the nasal passages are clean and not obstructed by mucus. This nasal congestion alternates between the right and left nostrils throughout the day and night. ³

The cognitive abilities of individuals changes with advancing age. Whereas other cognitive functions like short term memory, brain processing speed, attention, reasoning and assertion will gradually deteriorate with advancing age. From 3rd decade of life individual’s processing speed (i.e., speed with which various tasks involving cognitive brain performance) declines. This accounts most of the cognitive changes in elderly people. This slowing can impact the individual day to day performance of tasks or works that involves cognition. Memory retrieval is majorly affected with old age. Even visuo-spatial constructive abilities declines in older people. Reduced grey matter volume. Even loss of corpus callosum integrity mediating cognitive decline in ageing has been an evidence to show that cognition is negatively related to advanced age in older age group people. ⁴

Kyizom et al studied the effect of pranayama on brain cognitive functions in diabetic patients (type 2). They measured P300 (P3) an evoked potential in diabetic patient and the effect of pranayama on this P300 which is a measure of brain higher function. With practice of pranayama and yoga there is a significant improvement in P300 latency concluding pranayama and yoga helps in improving cognitive functions of brain in diabetic patients. 5 Bhattacharya et al study showed, after regular practice of pranayama the lipid peroxide level reduced significantly, where as there was no significant increase in super oxide dismutase level concluding regular pranayama practice regulates the oxygen intake there by reduces the lipid peroxide levels in blood there by lowering the risks of damages caused by oxidative stress. ⁶

Our main aim is to study the effect of pranayama on cognitive and higher mental functions in normal healthy young adults.

METHODS & MATERIALS

Institutional ethical clearance was obtained for the current study. 100 apparently healthy medical students with equal male to female ratio (i.e., 50 males and 50 females) participated in this experimental pre-post study, voluntarily. The sample size was derived from the previous original research studies ¹, ³, ⁷ & ⁸ by using open-epi software.9 Informed consent had been taken from the participants after explaining the study procedure and they were free to leave the study with prior notice.

Inclusion criteria:
• 18-25 years age
• Non-Alcoholic
• Non-Smokers
Exclusion criteria: • People with hypertension, diabetes mellitus and respiratory illnesses
• Any clinical history of psychological or neurological disease or drug abuse etc.,
• Subjects who used to play sports or do regular exercise or practice yoga or pranayama previously.

Study Design: The study was conducted in clinical laboratory, department of physiology, Prathima institute of medical sciences. The participants daily attended the laboratory 2 hours post-lunch i.e., around 4.00 pm without fail for practising the pranayama. For the first 6 weeks they practised surya anulomvilom pranayama (right nostril breathing), 5 seconds deep inhalation followed by 5 seconds deep exhalation through right nostril only continuously for 10 minutes closing left nostril with the opposite hand index finger. ¹, ¹⁰ & ¹¹ The next 6 weeks they practised chandra anulomvilom pranayama (left nostril breathing), 5 seconds deep inhalation followed by 5 seconds deep exhalation through left nostril only continuously for 10 minutes closing right nostril with the opposite hand index finger. ¹, ¹⁰ & ¹¹ the above subjects were not allowed any other physical athletic activities or sports in that particular study period.

Assessment of cognitive function: The cognitive functions of participants before and after 12 weeks of practise of pranayama were assessed mainly by three tests. They are

1] Trail making test A: Trail Making Test A of 25 circles distributed over a sheet of paper. The circles are numbered 1 – 25, and the subject should draw lines to connect the numbers in ascending order. The subject should be instructed to connect the circles as quickly as possible, without lifting the pen or pencil from the paper. Record the final time taken by the subject to connect the "trail." ¹², ¹³

2] Trail making test B: In Part B, there are 25 circles similar to Trail making test A, but the circles include both numbers (1 – 13) and letters (A – L). As in Part A, the subjects draws lines to connect the circles in an ascending pattern, but with the added task of alternating between the numbers and letters (i.e., 1-A-2-B-3-C, etc.). The difficulty of Trail Making Test B is higher than Trail Making Test A and Trail Making Test B is the better tool at assessing cognitive function. ¹², ¹³ & ¹⁴ Results for both Trail Making Test A and B are reported as the number of seconds required to complete the task; therefore, lower scores reveal greater cognition. Trail Making Test is a simple and quick technique to assess visual attention and eye-hand coordination components of cognitive functions. 12

3] Mini-mental state examination: “It consists of simple questionnaire with each question carrying 1 point and max score is 30. Orientation – 10 points, Registration – 3 points, Attention and calculation – 5 points, Recall – 3 points, Language and praxis – 9 points and for a Total score of 30 points Mini mental state examination can be used to assess one’s orientation, registration, calculation, memory & recall, even language & praxis as a simple questionnaire and easy to do tasks with maximum scoring set at 30.” ¹⁵, ¹⁶ & ¹⁷ Interpretation of the test:

1. for trail making tests A & B the results were reported as time taken to complete the task. The lower the score (time taken to complete) the better is the cognition of participant.

2. Single cut-off value for mini-mental state examination is 24; if it is less than 24 the cognition is impaired, the higher the scores better is the cognition of participant.

The statistical analysis of results before and after 12 weeks of pranayama practise was done with help of statistician and SPSS 16 software using student-t test with P significance set at (P<0.05).

RESULTS

In males, after 12 weeks of regular pranayama practice, there is statistically highly significant (P<0.001) reduction in time taken to complete both trail making test a and trail making test b. At the end of 12 weeks, there is statistically highly significant (P<0.001) improvement in Mini mental state examination scores (table 1).

Table: 1, Comparison of Trail making test A, Trail making test B and Mini mental state examination scores in 50 males before and after 12 weeks of pranayama practise