Arousal vs. relaxation: a comparison of the neurophysiological and cognitive correlates of Vajrayana and Theravada meditative practices.
PLoS One January 1, 2014 Ido Amihai, Maria Kozhevnikov
Meditation practices from the Theravada tradition (Shamatha and Vipassana) produce a relaxation response with enhanced parasympathetic activation, while those from the Vajrayana tradition (Deity and Rig-pa) produce sympathetic activation and arousal. Vajrayana meditations also led to an immediate increase in cognitive task performance, indicating enhanced phasic alertness. EEG results showed distinct patterns between traditions but similar patterns within each tradition. The findings suggest that categorizing meditation by relaxation versus arousal is more accurate than the focused versus distributed attention dichotomy.