Brain sources of EEG gamma frequency during volitionally meditation-induced, altered states of consciousness, and experience of the self

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.

Study at a glance

Abstract

Multichannel EEG of an advanced meditator was recorded during four different, repeated meditations. Locations of intracerebral source gravity centers as well as Low Resolution Electromagnetic Tomography (LORETA) functional images of the EEG 'gamma' (35-44 Hz) frequency band activity differed significantly between meditations. Thus, during volitionally self-initiated, altered states of consciousness that were associated with different subjective meditation states, different brain neuronal populations were active. The brain areas predominantly involved during the self-induced meditation states aiming at visualization (right posterior) and verbalization (left central) agreed with known brain functional neuroanatomy. The brain areas involved in the self-induced, meditational dissolution and reconstitution of the experience of the self (right fronto-temporal) are discussed in the context of neural substrates implicated in normal self-representation and reality testing, as well as in depersonalization disorders and detachment from self after brain lesions.