Shamanism a practice by which a person communicates with the spirits can be found throughout the ancient worlds. Although shamanism takes many and varied forms around the world, what a shaman actually experiences whilst in trance is remarkably uniform. Almost all report leaving their bodies to journey to an otherworld where they meet and interact with spirits. The reason for such similarity lies within the mind itself and the shared neurobiology of every human. In fact, any one of us could have the same experience as a shaman if we put ourselves in trance.
Shamans have varied ways of entering trance but all attempt to slow brain waves from a beta state, the usual rhythm, through an alpha state (which corresponds to light meditation or engrossment in an activity), to a theta state or trance. Whereas some shamans might stay very still and concentrate on breathing or praying, others move about in frenetic dances or whirl like Dervishes. Both types of activity, paradoxically, lead to trance.
The reason for this paradox relates to the way our brains regulate our bodies. The sympathetic system of brain activity reacts to external stimuli. It creates arousal in the body through pleasure or pain. The parasympathetic system manages automatic processes such as breathing, sleeping, and digesting. It tends towards quiescence, that is, complete still and calm. The two work in opposition and keep our bodies in balance. Is it possible, however, to push either system to extreme. If we undertake physical activities that lead to hyper-arousal, we load the sympathetic system and the activity completely takes over so that we begin to lose ourselves in a state of flow. Similarly, if we undertake activities that lead to hyper-quiescence, we load the parasympathetic system and the mind begins to empty and turn inward.
Beyond hyper-arousal or hyper-quiescence lies a further state, where one system, usually quite separate, overflows and begins to spill over into the other. With hyper-arousal, this happens when our strenuous activity brings waves of tranquillity and stillness, such as the sensation after vigorous sex. The sympathetic system has overflowed and feelings now arise from the parasympathetic system. Similarly, with hyper-quiescence, there can be a point where deep meditation brings a rush of energy that quite overwhelms us. The parasympathetic system has overflowed and feelings now arise from the sympathetic system. In both cases, when one system overflows into another and our feelings no longer correspond to our actions, we experience an out-of-body sensation that is at the heart of shamanic trance.
The Breakdown Of Self-Identity
Many shamans report that gravity no longer tethers their bodies to the earth and they can fly through the air with little effort. Since the active neurons in the brain at this stage of trance have a spiralling tendency, a tunnel opens up before them, formed entirely within the eye retina itself. Shamans recognise this as a portal to the otherworld and they leave their physical bodies behind to travel down it. Limbs might grow longer or detach from the body as the perception of being in a physical form diminishes. These are the first signs that self-identity is breaking down as the overflow of the sympathetic and parasympathetic systems of the brain excludes any outside stimulus. The mind turns entirely inward. This overflow also causes a leaking of imagery from the unconscious mind into the conscious and, as the shaman steps out of the tunnel and enters the otherworld, they find themselves in a startling new reality.
The disintegration of the self continues and some shamanic communities now speak of terrible violence inflicted upon the body. This self-generated fear response stems from the over stimulation of the amygdala, a bunch of neurons that are responsible for orientating the body in space. When a shaman drums and dances with frenzied intensity, the amygadala starts to malfunction and this causes waves of fear, heightening the expectation of violence. Alternatively, with less frenzied activity, it may provoke feelings of religious awe.
Hallucinations start and one of the most common entities to appear is an animal. Scientists call this zoopsia, whereas shamans call them spirits. Although hallucinations arise from the preconscious part of the brain, there appears to be a definite pattern to them. Jung calls these archetypes and the wise teacher seems a particularly prevalent example from many cultures.
The Unconscious Mind
Since the body is losing its self-awareness, it appears to someone in trance that knowledge comes from a point outside the mind. Coupled with zoopsia it is not surprising that many shamans speak of guardian or power animals being a rich source of otherworldly wisdom: the wise teacher. Since the unconscious mind is leaking into the conscious mind, much of this wisdom might also appear novel and new.
It is not always an animal that fulfils the wise teacher archetype but it could also be another human, either living, dead, or entirely mythical. Seeing the dead whilst in trance may reveal the origin of belief in an afterlife and the survival of the soul after death. Many shamans speak of contacting their deceased ancestors whilst in shamanic trance.
As the self breaks down, there is a corresponding sense of unity with the rest of existence; there is no longer any individual identity. This may mean a person merges with whatever appears in front of them, such as their animal guide. Shamans often describe turning into an animals form and they call this shapeshifting. Others feel that they are one with the universe, as if all existence connects at this higher level. Everything appears to pulsate with energy and contain its own life force, giving rise to animism, the shamanic belief that all things are alive.
Eventually, any lingering sense of the self disappears entirely and all thoughts and experience appear to emanate from outside the body. Some discern an ultimate authority at this point; a controlling influence that lies beyond human existence and possibly beyond the world itself. It is not difficult for them to put a name to this supreme being: God.
The neurobiology of the human mind explains the similarities that underpin shamanism (and possibly all religions) around the world. Shamans see what they do because of their minds. Whether the otherworld and its spirits are merely hallucinations or are actually real is less easy to determine. That, like most other aspects of religion, is entirely a matter of individual faith and belief.