Beyond mindfulness: Arousal-driven modulation of attentional control during arousal-based practices.

Vajrayana (Tantric Buddhist) practices that modulate attentional control through arousal-driven influences, rather than through monitoring continuous thought processes as in mindfulness, produce distinct neural and physiological states. In 16 highly experienced practitioners, the generation stage (Yidam) and completion stage with sign (Tummo) induced parasympathetic withdrawal (arousal) and phasic alertness, seen as decreased high-frequency heart rate variability and increased alpha2 power. These states were later employed in Tantric Mahamudra, which led to high cortical excitability, non-selective focused attention, and reduced attentional control, with power reductions in all frequency bands except theta. In contrast, non-Tantric Mahamudra resembled mindfulness practices, with parasympathetic dominance, tonic alertness, and active monitoring, shown by increased alpha1 power and less pronounced decreases in other bands. A neurobiological model differentiating arousal-based and mindfulness-related practices is proposed.

Study at a glance

Abstract

Here we report meditative techniques, which modulate attentional control by arousal-driven influences and not by monitoring continuous thought processes as during mindfulness-related practices. We focus on Vajrayana (Tantric Buddhism) practices, during which a sequence of generation (self-visualization as a deity - Yidam) or completion with sign (inner heat -Tummo) stages necessarily precedes non-dual awareness (NDA) Tantric Mahamudra. We compared the electrocardiographic and electroencephalographic correlates of Mahamudra performed after rest (non-Tantric Mahamudra) with Mahamudra performed after Yidam (Tantric Mahamudra) in 16 highly experienced Vajrayana practitioners, 10 of whom also performed Tummo. Both Yidam and Tummo developed the state of PNS withdrawal (arousal) and phasic alertness, as reflected by HF HRV decreases and Alpha2 power increases, later neurophysiologically employed in Tantric Mahamudra. The latter led to the unique state of high cortical excitability, "non-selective" focused attention, and significantly reduced attentional control, quantified by power reductions in all frequency bands, except Theta. In contrast, similar to mindfulness-related practices, non-Tantric Mahamudra was performed in a state of PNS dominance (relaxation), tonic alertness, and active monitoring, as suggested by Alpha1 power increases and less pronounced decreases in other frequency bands. A neurobiological model of meditation is proposed, differentiating arousal-based and mindfulness-related practices.