Psychological Bulletin
January 1, 2005
Dieter Vaitl, Niels Birbaumer, John Gruzelier et al.
446 citations
Altered states of consciousness (ASC) can occur spontaneously, be evoked by physical or physiological stimulation, induced by psychological means, or caused by diseases. Psychological and neurobiological approaches reveal four dimensions characterizing ASC: activation, awareness span, self-awareness, and sensory dynamics. Neurophysiologically, different states of consciousness arise from compromised brain structure, transient changes in brain dynamics (disconnectivity), and neurochemical and metabolic processes. Environmental stimuli, mental practices, and self-control techniques can also temporarily alter brain functioning and conscious experience.
Psychiatry Research Neuroimaging
November 1, 2001
Dietrich Lehmann, P.L Faber, Peter Achermann et al.
212 citations
EEG recordings from an advanced meditator showed that different meditation states—visualization, verbalization, and dissolution of self—activate distinct brain regions. Gamma-band (35–44 Hz) activity patterns differed significantly across four meditations. Visualization engaged the right posterior brain, verbalization the left central area, and self-dissolution involved right fronto-temporal regions. These findings align with known functional neuroanatomy and are discussed in relation to self-representation, reality testing, depersonalization disorders, and brain lesions.
Human Brain Mapping
August 27, 2001
Edi Frei, Alex Gamma, Roberto D Pascual-Marqui et al.
175 citations
A single dose of MDMA (1.7 mg/kg) in 16 healthy, MDMA-naïve volunteers produced widespread decreases in slow and medium frequency brain activity and increases in fast frequency activity in the anterior temporal and posterior orbital cortex, as measured by scalp EEG and low resolution brain electromagnetic tomography (LORETA). These changes were accompanied by heightened mood, emotional arousal, and increased extraversion. The EEG pattern suggests that serotonin, noradrenaline, and, to a lesser degree, dopamine contribute to MDMA's effects on brain activity and possibly mood and behavior, indicating modulation of limbic orbitofrontal and anterotemporal structures involved in emotional processes.
Neuroreport
January 1, 2000
Alex Gamma, Edi Frei, Dietrich Lehmann et al.
81 citations
People who regularly use Ecstasy show altered brain activity patterns, including increased theta, alpha, and beta power across the scalp, particularly with eyes open, as measured by EEG and brain tomography. They also report higher levels of state depressiveness, emotional excitability, and a trend toward increased state anxiety compared to non-users. These differences could stem from regular Ecstasy or other illicit drug use, or may have existed before drug use began.
Psychology of Consciousness Theory Research and Practice
August 1, 2013
Dieter Vaitl, Niels Birbaumer, John Gruzelier et al.
43 citations
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Cognitive processing
February 1, 2015
Pascal L Faber, Dietrich Lehmann, Lorena R R Gianotti et al.
During Zazen meditation, experienced practitioners show increased alpha-1 and alpha-2 brain wave activity in a right-lateralized cluster spanning prefrontal areas, insula, somatosensory, motor, and temporal cortices compared to resting without a task. Decreased alpha and beta-2 activity occurs in the left angular gyrus, and decreased beta-1 and beta-2 activity in a large bilateral posterior cluster including visual cortex, posterior cingulate cortex, and parietal cortex. These patterns involve parts of the default mode network and suggest enhanced automatic memory and emotion processing alongside reduced conceptual thinking and self-reference, supporting a more detached moment-to-moment awareness during Zazen.
Brain Topography
November 1, 2009
Shisei Tei, Pascal L Faber, Dietrich Lehmann et al.
Long-term meditation practice may change the brain in ways that persist even when not meditating. Comparing Qigong meditators with non-meditators using EEG during rest, the meditators showed reduced activity in brain regions involved in judging or appraising, and increased activity in areas that process sensory information from inside and outside the body. These differences in delta brain waves suggest that the subjective experiences of greater awareness and detachment reported by experienced meditators are supported by lasting neuroplastic changes that carry over into everyday life.