Effect of Bhramari Pranayama on response inhibition: Evidence from the stop signal task

CONTEXT: Response inhibition is a key executive control processes. An inability to inhibit inappropriate actions has been linked to a large range of neurologic and neuropsychiatric disorders. AIMS: Examine the effect of Bhramari Pranayama (Bhpr) on response inhibition in healthy individuals. SETTINGS AND DESIGN: Thirty-one male students age ranged from 19-31 years from a residential Yoga University, Bengaluru, India were recruited for this study. We used a randomized self as control within-subjects design. Participants were counterbalanced randomly into two different experimental conditions (Bhpr and deep breathing (DB)). MATERIALS AND METHODS: Response inhibition has been measured using a standard tool Stop Signal Task (SST). Each session lasted for 50 min with 10 min for the experimental conditions, preceded and followed by 20 min of assessment. The primary outcome measure was stop signal reaction time (SSRT), an estimate of the subject's capacity for inhibiting prepotent motor responses. Additional measures of interest were the probability of responding on stop signal trials, P (r | s) and mean RT to go stimuli. RESULTS: The mean probability of responding on stop signal trials (P (r | s)) during Bhpr and DB are close to 50%, indicating reliable SSRT. Paired sample t-tests showed a significant decrease (P = 0.024) in SSRT after Bhpr session, while the DB group did not show any significant change. Further, t-tests show that the go RT increased significantly after Bhpr (P = 0.007) and no other changes/differences were observed. CONCLUSIONS: Bhpr enhanced response inhibition and cognitive control in nonclinical participants.