Chapter 27 Meditation and Neuroscience: From Basic Research to Clinical Practice

Meditation has been extensively practiced in many civilizations for thousands of years as a means of cultivating a state of well-being and for religious purposes. It has now started to be studied in terms of its influence on the brain and body and used in clinical settings. This chapter will first review meditation effects at the physiological, attentional, and affective levels and the scientific paradigms used to study these effects. A clinical application on emotion regulation will then be presented. Spiritual practices that aim at transcending the common state of consciousness can be found in human societies all over the world down to shamanic practices in the Paleolithic (Walter & Neumann Fridman, 2004; Winkelman, 2000). Formal references to meditation can be found in ancient texts as early as the third century BCE in the Buddhist wittings of the Abhidharma (Cox, 2004). Today, “meditation” is used as a generic term to refer to a wide range of practices for self-regulation of emotion and attention (Gunaratana, 2002) and is considered an inherently experiential practice present in most religious or philosophical traditions. Meditation generally involves focusing one’s attention on a particular physical or mental object. When mind wandering occurs, practitioners are instructed to bring their attention back to the meditative task. Meditation practices often involve altered states of consciousness although these typically only arise during intensive practices of several hours a day. Meditation practitioners often perform daily meditation for a period of time ranging from 15 minutes to several hours, with the goal of getting insight into the nature of their minds and the universe or reaching a state beyond the materialistic world and connecting with the infinite (or a divinity, depending on the meditation tradition). Based on the assumption that different conscious states are accompanied by different neurophysiological states, a neuroscientific approach to meditation focuses on altered sensory, cognitive, and self-awareness experiences. Meditation-induced neurophysiological changes may be of two kinds. Changes that occur during meditation practice are referred as state changes. Changes which build up over months or years and persist even when the mind is not actively engaged in meditation are referred to as trait changes (Cahn & Polich, 2006). On one hand, the study of meditation states is especially relevant for consciousness research as a means of exploring the effect of meditation itself on the brain. On the other hand, the study of meditation traits is more particularly adapted to the study of meditation’s beneficial effects on health and general wellbeing in association with potential clinical applications. There are a large number of distinct meditative practices, but given that self-regulation of attention is a major component that is common among all of them, it is possible to classify meditative style on a continuum, depending on how attentional processes are directed (Cahn & Polich, 2006). Lutz, Slagter, Dunne, and Davidson (2008) proposed a theoretical framework in which meditation practices are categorized in two main groups. Concentrative—or focused attention—techniques involve continuous sustained attention on a selected object: the object of focus may be breath or body sensations, a subvocal repeated sound or word (mantra), or an imagined mental image. Focused attention meditation requires the narrowing of awareness so that the mind only contains the object of focus. On the other hand, mindfulness meditation practices, also called open-monitoring or insight meditation, involve the expanding of awareness with no explicit focus (except awareness itself). In mindfulness, practitioners are instructed to allow any thought, feeling, or sensation to arise in consciousness while maintaining a nonreactive awareness to what is being experienced. Mindfulness may be described as sustained awareness aimed at nonreactive and nonattached mental observation, without cognitive or emotional interpretation of the unfolding moment-to-moment experience (Cahn & Polich, 2006; Gunaratana, 2002; KabatZinn, 2003; Lutz, Slagter, et al., 2008).