Group Consciousness in Ayahuasca Sessions

Here is a fascinating quote from Benny Shannon's Antipodes of the Mind.

The non-individuation of consciousness [under the influence of Ayahuasca] may also be manifested in the blurring of the distinction between the individual and his or her fellow human beings. As a consequence, one may feel that one's identity is defined not individually but rather in group terms. Thus, strong identification with the other persons who participate in the Ayahuasca session is common. One clear manifestation of this is the communal singing in the rituals of the Santo Daime Church. Many times I have observed how sessions begin - the leading persons start to sing and the others in the hall readily join in, as if tied to them by hidden strings. On such occasions, the group becomes a kind of a single organism that acts in a precise and highly concentrated fashion. Once I gave a cassette recording I had made of such singing for inspection to a musical laboratory equipped with high-tech measurement instruments. The experts were astonished at the perfect degree of synchrony between the people singing. (Antipodes of the Mind, p. 201, emphasis added)

I'm particularly fascinated in the above account by the fact that the experience of group consciousness manifested in a way that could be objectively measured. I'd love to hear about other manifestations of group consciousness effects if anyone wants to share.