Don et al (1989) report increased 40HZ EEG activity associated with clairvoyance hitting in an exceptional psychic, this being repeated with another person in a later study (McDonough,1989). Don et al (1996) recorded EEGs from 11 members of a Brazilian shamanistic religion which uses ayahuasca. Analyses showed increases in power in the 40 HZ region, consistent with reports that ayahuasca intensifies visual imagery. They interpret these results as supporting the proposal by Llinas & Ribary (1993) that the 40HZ rhythm is linked with the consciousness-generating mechanism which produces the REM state, hallucinations and daydreaming states, and further suggest that this “may also underly the conscious elaboration of initially unconscious or preconscious psi information.” They think that the claimed psychic effects of ayahuasca are due to 40 Hz brain activity making unconscious psi information available to the conscious mind.

Don & Moura (1997) analysed the EEGs of people claiming contact or abduction UFO experiences who later spontaneously had altered states of consciousness or trance experiences. This showed a state of hyperaroused trance in which the muscles were relaxed and immobile whilst their EEGs exhibited high frequency 40 Hz beta activity at all 19 electrode sites, with maximum activity at the prefrontal and adjacent loci. There were intermittent trains of rhythmic approximately 40 Hz activity attaining very high amplitudes at times exceeding 40 microvolts, which was distinct from muscle discharge, significantly more in trance than in baseline. Also the dominant alpha frequency increased during trance. There have been numerous observations of increased fast beta activity in schizophrenia patients (Itil, 1977) but this tends to include delta, theta, alpha and low beta activity as well. Also in schizophrenia the beta activity is observed mostly at sites posterior to the frontal scalp. Most importantly UFO experiencers can voluntarily commence and terminate the high frequency activity which was only present in the trance condition; voluntary control is not found in schizophrenics. Das & Gastaut (1957) found a similar EEG in a yogi in advanced meditation, in the state of samadhi. They suggest that UFO experiencers enter this ecstasy trance state, some of the experiencers reporting feeling that they were linked to a higher consciousness and sometimes connected with a non-human being or even with God. The difference is that samadhi is experienced after years of training whereas the UFO people experienced it as a result of their abduction of contact.

Llinás has proposed that the thalamic intralaminar nuclei which comprise the diffuse thalamic system generate 40 Hz activity which integrates corticothalamic activity and so bears importantly on consciousness. Sheer (1984) found that scalp-recorded 40 Hz was associated with focused arousal and learning tasks. It appears that as the focus of attention sharpens, the integrative activity of the thalamic system increases through the action of 40 Hz rhythms. Apparently when attentional focusing becomes laser-like an extreme state of corticothalamic integration occurs and with it an amplification of normally unconscious brain activity, with a higher-order self or personality prevailing which seems to transcend time and space. However the UFO experiencers did not show the high frequency brain activity widely spread all over the scalp as did the yogis. Theirs was centred on the prefrontal loci of the brain. In samadhi one experiences Divine Union. The UFO people experienced a wider range of phenomena.
This EEG research suuports the neurochimical findings with regard to the commonalities between the various primary process states of consciousness of psychics, spiritual people and visionaries. In section 4.2. we will look at Llinas hypothesis which links these with the dream state of consciousness.

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