"The existence of a universal drive among humans for altering consciousness is strongly supported by cross-cultural research.
Institutionalized procedures for ritually altering consciousness have been documented in virtually all societies of the world, reflecting a commonality of culture and religion.
Bourguignon (1968) reported evidence that approximately 90 percent of the societies in a worldwide sample had institutionalized rituals for altering consciousness, suggesting it was likely a cultural universal.
In another cross-cultural study, Winkelman (1986, 1992) found that communal ritual involving ASC (altered states of consciousness) were a cultural universal; all societies have magico-religious practictioners who have their professional roles based in powers derived from the modification of consciousness . . .
Even when there is cultural repression of the IMC, experiences of this realm of consciousness nonetheless manifest spontaneously and idiosyncratically because they reflect a biological basis.
Eliciting the IMC may be achieved in numerous ways, including pushing psychological functions beyond their limits, disrupting subsystems by sensory overload or deprivation, manipulating the autonomic nervous system balance, or focusing or withdrawing attention . . .
There are widespread biases against some forms of altered consciousness in Western society and cultures. Historically, such manifestations were persecuted through witchcraft accusations. Western psychology has tended to consider shamanic-type experiences to be pathological or 'primitive,' manifested in the perspectives that meditative states are regressions to infantile levels . . .
A contrastive approach is found in the many cultures that have viewed hallucinogens as entheogens, sacred plants that produce a contact with the divine. Meditative traditions indicate that altering consciousness provides a variety of adaptive advantages through the development of a more objective perception of the external world . . .
The desire to alter consciousness is an innate, biologically based human drive with adaptive significance, a manifestation of a fundamental homeostatic dynamic of the nervous system . . .
This intensification of the linkages of the lower brain structures, paleo-mammalian brain, and frontal brain structures produces a synthesis of behavior, emotion, and thought . . .
The wide range of procedures used cross-culturally to induce these conditions reflects the ability of diverse agents and conditions to evoke this natural potential of the human brain-mind. The IMC is a physiologically based mode of organismic functioning and integration that produces a condition of homeostatic balance . . .Winkelman, Michael M. (2010). Shamanism: A Biopsychosocial Paradigm of Consciousness and Healing. Santa Barbara: Praeger.
The shaman is a technician of consciousness who uses these potentials for acquiring information, healing and personal and social transformation (p. 4-5)."