Middle Latency Auditory Evoked Response during High-frequency Yoga Breathing, Breath Awareness, and Quiet Rest.

Background: Yoga breathing influences cortical activity and, hence, cortico-efferent sensory activity. Previously, slow yoga breathing influenced the components of mid-latency auditory evoked potentials.

Objective: The present study aimed to compare middle latency auditory evoked potentials (MLAEPs) recorded during (i) High-frequency yoga breathing (HFYB), (ii) Breath awareness (BAW), and (iii) Quiet rest (QR) as a control in experienced yoga practitioners.

Materials and methods: The MLAEPs were recorded before, during, and after the practice of HFYB compared to an equal duration of BAW and QR in 22 university students whose ages ranged from 18 to 28 years, recorded from the vertex referenced to linked earlobes and the ground electrode on forehead.

Results: The peak amplitude of the Pa wave was significantly increased during HFYB compared to before HFYB (repeated measures ANOVA, post hoc analysis with least significant difference, P < 0.05). During BAW, the peak amplitude of the Na wave was significantly increased compared to before BAW (P < 0.05). During QR, the peak latency of "Pa" and "Nb" waves was significantly increased compared to before QR (P < 0.01).

Conclusions: The findings suggest that changes in MLAEPs during HFYB, BAW, and QR were different and distinct. Both interventional sessions appear to increase the recruitment of neural resources in the primary auditory cortex, whereas QR appears to slow transmission within the thalamic reticular projection to the cortex. Generalizing the findings is restricted by the sample being confined to male experienced practitioners of yoga breathing.