Indian J Physiol Pharmacol 2008 52 (2) 197-200 SHORT COMMUNICATION IMMEDIATE EFF
ID: 3443762 • Letter: I
Question
Indian J Physiol Pharmacol 2008 52 (2) 197-200 SHORT COMMUNICATION IMMEDIATE EFFECTS OF RIGHT AND LEFT NOSTRIL BREATHING ON VERBAL AND SPATIAL SCORES MEESHA JOSHI AND SHIRLEY TELLES Swami Vivekananda Yoga Research Foundation Bangalore 560 019 (Received o November 1. 2007) AbstractThe immediate effect of two yoga breathing techniques was assessed on verbal and spatial memory tasks, considered hemisphere-specific Forty-five participants (24 males; age range 20 to 45 years (mean age 27. I ±8.1 years) were randomly allocated to three groups (n-15 each) and were assessed immediately before and after 45 minutes of three breathing practices i.e., right nostril yoga breathing, left nostril yoga breathing, or breath awareness as a control intervention. Spatial memory scores increased after left nostril yoga breathing compared to before (by 16 percent, P-0.03 paired t-test). Hence, breathing through the eft nost increased performance in a spatial cognitive task, corresponding to the cerebral hemisphere contralateral to the patent nostril Key words:Yoga voluntarily regulated breathing spatial memory verbal memory INTRODUCTION phases of the nasal cycle was first studied in eight subjects who were asked to perform The nasal cycle is characterized by verbal and spatial tasks every alternating patency of the nostrils every two for eight hours (3). Spontaneous changes in to eight hours (, with a rhythmic and nostril dominance brought about changes in alternating shift of activity in the autonomic cognitive performance. The best performance nervous system and cerebral activity (2) on the verbal task was 180 degrees out of Alternating cerebra activity facilitaes phase with the best performance on the performance in cerebral hemisphere specific spatial task tasks along with relatively greater EEG amplitudes recorded contralateral to the dominant nostril Similar ress were reported with unilateral forced nostril breathing. A study on undergraduate students who practiced Alternating cognitive performance with forced left uni-nos breathing showed Corresponding AuthorDr. Shirley Telles. Ph.D., Patajai Yogpeeth, Maharishi Gayanand Gra, New Delhi Haridwar Highway, Bahadrabad, Haridwar (Uttarakhand)- 249408 Telephone: +91-01334-244805: Telefax +91-01334-244805Explanation / Answer
The internal validity of the study is determined by the degree to which the study reduces systematic errors or biases. It appears that the study does not employ robust measures to ensure internal validity. The literature review is inadequate and therefore it’s theoretical foundation can be questioned. In addition, there are some methological concerns as well because the sample size is quite small (15 participants in each group) and the socioeconomic and demographic details have not been taken into consideration at all. Similarly, the external validity of a study is the degree to which its findings can be generalised to other contexts. I would say that the external validity is also not strong enough, as the study uses simple cognitive tasks a basis for making assumptions about the left and right hemisphere brain functions, that are quite complex in nature.