Elsevier

Biological Psychology

Volume 82, Issue 1, September 2009, Pages 1-11
Biological Psychology

Review
The neurobiology of Meditation and its clinical effectiveness in psychiatric disorders

https://doi.org/10.1016/j.biopsycho.2009.04.003Get rights and content

Abstract

This paper reviews the evidence for changes of Meditation on body and brain physiology and for clinical effectiveness in disorders of psychiatry. The aim of Meditation is to reduce or eliminate irrelevant thought processes through training of internalised attention, thought to lead to physical and mental relaxation, stress reduction, psycho-emotional stability and enhanced concentration. Physiological evidence shows a reduction with Meditation of stress-related autonomic and endocrine measures, while neuroimaging studies demonstrate the functional up-regulation of brain regions of affect regulation and attention control. Clinical studies show some evidence for the effectiveness of Meditation in disorders of affect, anxiety and attention. The combined evidence from neurobiological and clinical studies seems promising. However, a more thorough understanding of the neurobiological mechanisms of action and clinical effectiveness of the different Meditative practices is needed before Meditative practices can be leveraged in the prevention and intervention of mental illness.

Introduction

Neuropsychiatric disorders such as depression, alcohol and drug abuse are on the increase worldwide. Neuropsychiatric disorders account for 31% of total disability and are expected to rise by 2020 (Mathers and Loncar, 2005). Depression is the most common of all mental disorders with the greatest public health burden. According to estimates from the World Health Organisation (WHO) by 2020 depression will be the leading cause for disability worldwide. Suicide is estimated to be the leading cause of death in young people in 2020 (Mathers and Loncar, 2005). There have been increases in the number of diagnoses of mental health problems including schizophrenia, dementia, alcohol and substance abuse, and most child psychiatric disorders, which in part may be confounded by better detection, improved services and diagnostic changes. Nevertheless, these will be an increasing part of the overall health burden in the future.

Currently, there is no long-term cure of mental illness. Conventional behavioural or pharmacological treatment, though not a cure, has shown effectiveness in the alleviation of symptoms. However, dissatisfaction has arisen with psychopharmacological interventions due to side effects, its escalating prescription rates in both adults and children, and recent uncertainties on the effectiveness and long-term benefits of some psychopharmacological treatments such as antidepressants and psychostimulants (Jensen et al., 2007, Kirsch et al., 2008). Innovative conceptual and therapeutic models of care continue to emerge that may be relevant to the amelioration of mental illness. One of these is Meditation. Meditation has in recent years received considerable attention as a potential adjunct or alone in the intervention of psychiatric disorders as it is cost-effective and presumably free of side effects. In this paper we discuss the physiological and neurophysiological underpinnings of the subjectively reported benefits of Meditation and its potential effectiveness as a complementary treatment approach for mental illness.

Section snippets

What is Meditation and why could it be a useful adjunct to achieve mental health?

Meditation is essentially a physiological state of demonstrated reduced metabolic activity – different from sleep – that elicits physical and mental relaxation and is reported to enhance psychological balance and emotional stability (Jevning et al., 1992, Young and Taylor, 2001). In Western psychology, three states of consciousness are described: sleep, dream and wakefulness. In Eastern philosophy and in several Western religious and mystical traditions, an additional and supposedly “higher”

Peripheral physiological changes during Meditation

Studies comparing experienced Meditators compared to controls or short-term Meditators have demonstrated physiological changes during Meditation suggestive of a wakeful hypometabolic state that is characterised by decreased sympathetic nervous activity, important for fight and flight mechanisms, and increased parasympathetic activity, important for relaxation and rest (Cahn and Polich, 2006, Jevning et al., 1992, Rai et al., 1988, Young and Taylor, 2001). This wakeful hypometabolic state with

Neurophysiological effects during Meditation

As mentioned before, the key subjective experiences in Meditation, apart from a general relaxation response, are the reduction of mental activity and the generation of positive affect. Functional neuroimaging studies have in fact been able to corroborate these subjective experiences by demonstrating the up-regulation in brain regions of internalised attention and emotion processing with Meditation.

Many electrophysiological studies have examined the brain activation during a variety of

Evidence for long-term benefits of Meditation

The majority of Meditation studies have investigated the physiological and neurobiological correlates of the acute effects of Meditation. Clinically more interesting, however, is whether Meditation has sustainable effects on cognitive functions, brain plasticity and mental health. Very few studies have provided evidence for long-term, sustainable effects.

Evidence exists for long-term improvements with Meditation in cognitive skills, mainly in the domains of attention, inhibitory control and

Specificity of the neural substrates of Meditation compared to relaxation

It has been argued that Meditation is not different from simple relaxation. And there are certainly some Meditation techniques that do not claim to go beyond relaxation. Nevertheless, one would expect the neurobiology of the more concentrative Meditation techniques to differ from that of general relaxation, given that in addition to relaxing the body these “cognitive relaxation” techniques aim at reducing mental activity, hence also relaxing the mind. Mental relaxation, in turn, may feedback to

Clinical effectiveness of Meditation in psychiatric disorders

Given the preliminary but growing evidence for short and long-term effects of Meditation on physiological indicators of stress, on personality and cognitive functions, and on functional and structural plasticity of brain regions that are important for attention and emotion regulation, mental disorders, typically characterized by affective and cognitive-attentional problems, are an obvious target to study the clinical effects of Meditation.

Research of the clinical application of Meditation

Overall conclusions

Several Meditation techniques appear to have short and long-term effects on functional and structural brain plasticity as well as on physiological indicators of relaxation and stress relief. There is evidence to suggest that these effects are specific to Meditation over and above simple relaxation effects. There is furthermore preliminary evidence for enhanced psycho-emotional balance and focussed attention skills in long-term Meditators. The up-regulating functional effects on fronto-parietal

References (107)

  • N. Janakiramaiah et al.

    Antidepressant efficacy of Sudarshan Kriya Yoga (SKY) in melancholia: a randomized comparison with electroconvulsive therapy (ECT) and imipramine

    Journal of Affective Disorders

    (2000)
  • N. Jausovec et al.

    Differences in induced gamma and upper alpha oscillations in the human brain related to verbal/performance and emotional intelligence

    International Journal of Psychophysiology

    (2005)
  • P.S. Jensen et al.

    3-Year follow-up of the NIMH MTA study

    Journal of the American Academy of Child and Adolescent Psychiatry

    (2007)
  • R. Jevning et al.

    The physiology of meditation – a review – a wakeful hypometabolic integrated response

    Neuroscience and Biobehavioral Reviews

    (1992)
  • F. Karaaslan et al.

    P300 changes in major depressive disorders with and without psychotic features

    Journal of Affective Disorders

    (2003)
  • T.W. Kjaer et al.

    Increased dopamine tone during meditation-induced change of consciousness

    Cognitive Brain Research

    (2002)
  • A.L. Krain et al.

    Brain development and ADHD

    Clinical Psychology Review

    (2006)
  • A.O. Massion et al.

    Meditation, melatonin and breast prostate-cancer—hypothesis and preliminary data

    Medical Hypotheses

    (1995)
  • L.K. McEvoy et al.

    Test–retest reliability of cognitive EEG

    Clinical Neurophysiology

    (2000)
  • J.J. Miller et al.

    3-year follow-up and clinical implications of a Mindfulness Mediation-based stress reduction intervention in the treatment of anxiety disorders

    General Hospital Psychiatry

    (1995)
  • Y. Nagai et al.

    Activity in ventromedial prefrontal cortex covaries with sympathetic skin conductance level: a physiological account of a “default mode” of brain function

    NeuroImage

    (2004)
  • A. Newberg

    The measurement of regional cerebral blood flow during the complex cognitive task of meditation: a preliminary SPECT study

    Psychiatry Research: Neuroimaging

    (2001)
  • C. Pacchierotti et al.

    Melatonin in psychiatric disorders: a review on the melatonin involvement in psychiatry

    Frontiers in Neuroendocrinology

    (2001)
  • C.J. Rennie et al.

    Mechanisms of cortical electrical activity and emergence of gamma rhythm

    Journal of Theoretical Biology

    (2000)
  • C.A. Stockmeier

    Involvement of serotonin in depression: evidence from postmortem and imaging studies of serotonin receptors and the serotonin transporter

    Journal of Psychiatric Research

    (2003)
  • R. Sudsuang et al.

    Effect of Buddhist Meditation on serum cortisol and total protein-levels, blood-pressure, pulse-rate, lung-volume and reaction-time

    Physiology & Behavior

    (1991)
  • G.A. Tooley et al.

    Acute increases in night-time plasma melatonin levels following a period of meditation

    Biological Psychology

    (2000)
  • F. Travis et al.

    Cortical plasticity, contingent negative variation, and transcendent experiences during practice of the Transcendental Meditation technique

    Biological Psychology

    (2000)
  • F.T. Travis et al.

    Patterns of EEG coherence, power, and contingent negative variation characterize the integration of transcendental and waking states

    Biological Psychology

    (2002)
  • L. Aftanas et al.

    Impact of regular meditation practice on EEG activity at rest and during evoked negative emotions

    International Journal of Neuroscience

    (2005)
  • L.I. Aftanas et al.

    Linear and non-linear concomitants of altered state of consciousness during meditation: high resolution EEG investigation

    International Journal of Psychophysiology

    (2002)
  • L.I. Aftanas et al.

    Changes in cortical activity in altered states of consciousness: the study of meditation by high-resolution EEG

    Journal of Human Physiology

    (2003)
  • American Psychiatric Association

    Diagnostic and Statistical Manual of Mental Disorders

    (1994)
  • A.J. Arias et al.

    Systematic review of the efficacy of meditation techniques as treatments for medical illness

    Journal of Alternative and Complementary Medicine

    (2006)
  • T. Barnhofer et al.

    Effects of meditation on frontal alpha-asymmetry in previously suicidal individuals

    Neuroreport

    (2007)
  • J.A. Brefczynski-Lewis et al.

    Neural correlates of attentional expertise in long-term meditation practitioners

    Proceedings of the National Academy of Sciences of the United States of America

    (2007)
  • D. Brown et al.

    Differences in visual sensitivity among mindfulness meditators and non-meditators

    Perceptual and Motor Skills

    (1984)
  • R.P. Brown et al.

    Sudarshan Kriya yogic breathing in the treatment of stress, anxiety, and depression. Part II. Clinical applications and guidelines

    Journal of Alternative and Complementary Medicine

    (2005)
  • A. Brzezinski

    Melatonin in humans

    New England Journal of Medicine

    (1997)
  • M. Bujatti et al.

    Serotonin, noradrenaline, dopamine metabolites in transcendental meditation-technique

    Journal of Neural Transmission

    (1976)
  • B.R. Cahn et al.

    Meditation states and traits: EEG, ERP, and neuroimaging studies

    Psychological Bulletin

    (2006)
  • T. Canli et al.

    Hemispheric asymmetry for emotional stimuli detected with fMRI

    Neuroreport

    (1998)
  • D. Chugh

    The effects of Sahaja Yoga in bronchial asthma and essential hypertension

    New Delhi Medicos N13

    (1997)
  • H.D. Critchley et al.

    Neural systems supporting interoceptive awareness

    Nature Neuroscience

    (2004)
  • H.D. Critchley et al.

    Brain activity during biofeedback relaxation: a functional neuroimaging investigation

    Brain

    (2001)
  • M.P. Deiber et al.

    Distinction between perceptual and attentional processing in working memory tasks: a study of phase-locked and induced oscillatory brain dynamics

    Journal of Cognitive Neuroscience

    (2007)
  • N.A.S. Farb et al.

    Attending to the present: mindfulness meditation reveals distinct neural modes of self-reference

    Social Cognitive and Affective Neuroscience

    (2007)
  • A. Gevins et al.

    Neurophysiological measures of working memory and individual differences in cognitive ability and cognitive style

    Cerebral Cortex

    (2000)
  • A. Gevins et al.

    High-resolution EEG mapping of cortical activation related to working memory: effects of task difficulty, type of processing, and practice

    Cerebral Cortex

    (1997)
  • R.H. Grabner et al.

    Neural efficiency in tournament chess players: a matter of expertise or intelligence?

    Journal of Psychophysiology

    (2005)
  • Cited by (184)

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