Studies on Meditation and the Brain
Meditation states and traits: EEG, ERP, and neuroimaging studies (pdf)Psychol Bull. 2006 Mar;132(2):180-211. PMID: 16536641
Cahn BR, Polich J.
This is a very big review of EEG, evoked potential, & neuroimaging studies of meditative states from many different meditative traditions.
From the conclusions in the EEG based section,
* increased power in theta and alpha bands
* decreased frequency at least in the alpha band
* overall slowing and alteration of coherence and gamma effects."
Long-term meditators self-induce high-amplitude gamma synchrony during mental practice
Proc Natl Acad Sci U S A. 2004 Nov 16;101(46):16369-73. PMID: 15534199
Lutz A, Greischar LL, Rawlings NB, Ricard M, Davidson RJ.
* high-amplitude gamma and phase-synchrony during unconditional loving-kindness and compassion meditation
Image at right shows areas as percent of subjects with increased gamma 25-42 Hz during meditation, particularly bilaterally over the parieto-temporal (roughly T3-T5 and T4-T6) and midfrontal areas (roughly F3 & F4).
Spectral analysis of the EEG in meditation (pdf)
Electroencephalogr Clin Neurophysiol. 1973 Aug;35(2):143-51. PMID: 4124606
Banquet JP.
Among TM meditators with average experience of 2 years
* Alpha rhythm increased in amplitude, slowed down in frequency and spread to anterior
* Theta frequencies different from those of sleep spread to posterior
* Rhythmic amplitude-modulated beta waves over the whole scalp around 20 and 40 Hz
* Anterior-posterior synchronization
An electroencephalographic study on the zen meditation (Zazen).
Folia Psychiatr Neurol Jpn. 1966;20(4):315-36. PMID: 6013341
Kasamatsu A, Hirai T.
This study identifies several stages during Zen meditation. Electrodes were at Fz, Cz, Pz, & Oz.
1: appearance of alpha waves in spite of opened eyes.
2: increase in amplitude of persistent alpha waves.
3: decrease of alpha frequency.
4: appearance of rythmical theta train.
These stages were found to be correlated both with years of Zen training as well as evaluation of the disciples by the Zen master.
Book: "Psychophysiology of Zen" 1974 Hirai T.
* increased alpha and theta amplitudes, particularly over the frontal lobes
Book: "The Relaxation Response" 1975 Benson H.
Benson outlines the essential elements of meditation
1: quiet environment
2: repetitive mental device
3: passive attitude
4: comfortable position
Also see relaxationresponse.org
Andrew Newberg's research on Tibetan Meditators
During peak meditation experience of "oneness"
* Frontal lobes more active (~ more beta)
* Posterior superior parietal lobes less active (~ more alpha)
Website/Book: The Physical and Psychological Effects of Meditation
Institute of Noetic Sciences
* Increased alpha and theta
* Occasional bursts of beta
* Alpha coherence
Richard Soutar's page on Neuro Meditation
Also check out his Brainmaps of meditators
Effects of an EEG biofeedback protocol on a mixed substance abusing population (pdf)
Am J Drug Alcohol Abuse. 2005;31(3):455-69. PMID: 16161729
Scott WC, Kaiser D, Othmer S, Sideroff SI.
Nice study expanding on the Alpha-Theta protocol that Peniston used successfully on alcoholics. Elmer Green referred to Alpha-Theta as instrumental vipassana. Here alpha 8-11 Hz and theta 5-8 Hz are rewarded at Pz.