Indeed, it is true to say that in the majority of cases the medium is unaware of the phenomena being displayed while he/she is in trance. The most extraordinary claims, therefore, derive not from the medium but from the sitters: it is the sitters who hear voices and bangs, perceive spirit lights and transfiguration, witness levitation and feel the solidity of ectoplasmic materialisations.
What, then, is going on?
There is a wide range of techniques for the attainment of altered states of consciousness, ranging from the consumption of psychoactive substances to meditation and all that is in between (e.g. sleep). Different techniques produce different phenomenological states, is there evidence for the induction of altered states of consciousness within the sitters as well as the medium? This section will venture to explore one of the possibilities (it is intended that other issues pertaining to this aspect of the seance will be elaborated on in later sections).
One of the simplest methods of consciousness alteration is sensory deprivation. Experiments concerning the effects of sensory and perceptual deprivation have demonstrated the sort of experiences people undergo in such circumstances: visual and auditory hallucinations are common (Vernon, 1971, p.170-173).
When we consider hallucinations it is common for us to regard them as symptoms of abnormality and as purely mental productions with no “objective” reality outside of the individual’s perception. Such a notion is, however, by no means universal: Richard Noll (1985) has suggested that the cultivation of mental imagery is a hallmark of shamanic societies around the world. In such societies endogenous imagery is considered to be a valuable tool, providing a means to catch a glimpse of a world that cannot otherwise be seen. Mircea Eliade (1989) has suggested that seeing a spirit is a hallmark of shamanic development:
““Seeing” a spirit, either in dream or awake, is a certain sign that one has in some sort obtained a “spiritual condition”, that is, that one has transcended the profane condition of humanity. This is why, among the Mentaweians, the “vision” (of spirits), whether occurring spontaneously or obtained by effort, immediately confers magical power” (Eliade, 1989, 85)
Visions are clearly a significant, and hence desired, phenomenon in a great many societies throughout the world. Indeed, there are themes within contemporary mediumship practice which suggest the importance of sensory deprivation for the cultivation of visual “hallucinations”, most notably the use of blackout (or red lighting) conditions and the positioning of the medium within a curtained cabinet.
The process of closing the medium off from view can be paralleled with the symbolic significance of the Hmong shaman, who, when entering into trance, covers his eyes with special blinkers. This act demonstrates that the shaman is no longer using his eyes to see in the physical world, but is instead looking beyond it into the spirit world: there has been a shift in focussed awareness.
Hmong Shaman, Thailand (Source)
Sensory deprivation, whether the product of sitting in blackout, wearing blinkers, or simply closing the eyes, provides the individual with an opportunity to focus attention inwards (or at least away from his/her physical environment), without (or with fewer) distracting sense impressions. Castillo (1995) has suggested that the ability to enter in to trance, both pathological and otherwise (27) is derived from an ability to narrowly and intensely focus attention onto inner processes. Trance and other (sleep, hypnosis, meditation, etc.) states of consciousness represent different “tunings” (Castillo, 1995, 27) of the central nervous system which differ to that of “normal waking consciousness" .
But what is it that the sense deprived individual perceives?
The terms "phosphene" and "entoptics" are used to refer to the sort of visual phenomena observed when an individual is subjected to sensory deprivation. Phosphenes/Entoptics are understood to be endogenous visual phenomena, that is they are a product of the structure of the eye and nervous system. Do these phenomena correlate in any way with the observations of individuals sitting in blackout (or red-lit) seance conditions?
Examples of common entoptic hallucinations (Horowitz, 1964, p.518)
The sort of visual phenomena commonly reported following sitting in seance conditions include:
- Spirit lights (of which there are seemingly a variety of different sorts; ranging from minute flashes of light to solid and constant orbs of light)
- Mists (often considered to be ectoplasm in a more subtle form)
- Transfiguration (whereby the medium's face is seen to shift between his/her own likeness and that of many others)
There is clearly a distinction to be made between the different forms of visual phenomena observed. There are certain visual phenomena, such as mists and spirit lights, that might be identified as entoptic hallucinations, and then there are those that do not seem to fall so neatly into this category, such as apparitional and transfiguration phenomena.
It becomes even more difficult when we consider the claims of individuals to have witnessed (visually and tactilely) full form materialisations and other definitely physical phenomena such as levitation and dematerialization. Can these fantastic claims be reduced to notions of endogenously derived subjective hallucinations, brought about through sensory deprivation?
Not really. These phenomena must fall into a different classification entirely. Either they are hallucinations of a much greater magnitude, or they represent objective occurrences (either genuine or the product of trickery, these are matters that will be brought up at a later date).
There are a variety of processes in action during the seance situation all of which culminate in the overall effect of the proceedings. To my mind the notion of altered states of consciousness in the sitters has been somewhat ignored (although perhaps I am wrong). It seems to me to be an important issue, and one which clearly stands out when we look at the facts. There are similarities in contemporary mediumship practice with other traditions of spirit seership from across both time and space.
Our culture has an inherent aversion to altered states of consciousness, and would consider them abnormal, so that anything encountered or observed while experiencing such a state cannot have any reality: they become labelled as "anomalous" and insignificant. This is not the case. Using the term hallucination to describe certain of the phenomena observed during blackout séances need not necessarily imply that there is no intrinsic reality to what is seen and heard. Altered states of consciousness may be considered as lenses of different magnifications, each state allowing a more detailed perspective on a particular facet of existence; allowing us to see what is already there, just below the surface of our everyday waking world.
These issues, and more, will be explored in greater depth as this site develops.
Thoughts, opinions and suggestions are welcomed.
 Horowitz, M.J. 1964. The Imagery of Visual Hallucinations. Journal of Nervous & Mental Disorders, Vol. 138, pp. 513-523.
 Castillo, R.J. 1995. Culture, Trance and the Mind-Brain. Anthropology of Consciousness, Vol. 6, No. 1, pp. 17-32.