Changes in P300 following alternate nostril yoga breathing and breath awareness

Abstract

This study assessed the effect of alternate nostril yoga breathing (nadisuddhi pranayama) on P300 auditory evoked potentials compared to a session of breath awareness of equal duration, in 20 male adult volunteers who had an experience of yoga breathing practices for more than three months. Peak amplitudes and peak latencies of the P300 were assessed before and after the respective sessions. There was a significant increase in the P300 peak amplitudes at Fz, Cz, and Pz and a significant decrease in the peak latency at Fz alone following alternate nostril yoga breathing. Following breath awareness there was a significant increase in the peak amplitude of P300 at Cz. This suggests that alternate nostril yoga breathing positively influences cognitive processes which are required for sustained attention at different scalp sites (frontal, vertex and parietal), whereas breath awareness brings about changes at the vertex alone.

Figure 1

Schematic representation of the design of the two sessions. The P300 was recorded before and after the intervention. Periods of recording are shown as hatched and periods of intervention are shown as stippled.

Figure 2

A single sample of a P300 waveform. The traces on the right show the responses to target stimuli before (2) and after (4) ANYB, showing an increase in P3 amplitude after ANYB (4) compared to before (2). Traces on the left show the response to standard stimuli before (1) and after (3) ANYB, with no change.