Effect of transcendental meditation on breathing and respiratory control

Transcendental meditation reduces breathing rate and the response to carbon dioxide. Experienced meditators showed a significant decrease in minute ventilation during meditation, from 14.0 to 12.4 liters per minute, due to a shorter inspiratory time and smaller tidal volume. Their breathing response to rising carbon dioxide levels also dropped, from 3.7 to 2.5 liters per minute per Torr. Control subjects showed no such changes. These findings indicate that a subtle shift in wakefulness, distinct from sleep, can alter the chemical and neural control of breathing.

Study at a glance

Abstract

We studied the effect of transcendental meditation (TM) on breathing using 16 experienced meditators and 16 control subjects. In controls, there was no significant difference in minute ventilation (VE), respiratory pattern, or hypercapnic response, whether breathing with eyes open-awake (CA), or with eyes closed-relaxing (CR). In meditators, VE decreased significantly during quiet breathing from 14.0 +/- 0.7 1/min with eyes open-awake (MA) to 12.4 +/- 0.6 1/min during meditation (MM) (P less than 0.02). The change in VE during meditation was due to a decrease in tidal volume (VT) resulting from a shortened inspiratory time (TI). Meditation was associated with a decreased response to progressive hypercapnia from 3.7 +/- 0.4 to 2.5 +/- 0.21 X min-1 X Torr-1 during MA and MM trials, respectively (P less than 0.01). During meditation VT was smaller at a given alveolar PCO2 than during MA studies because of a decrease in mean inspiratory flow rate (VT/TI). These observations suggest that an alteration in wakefulness, more subtle than sleep or the unconscious state, can significantly affect the chemical and neural regulation of breathing.