In terms of the 'Greyson NDE Scale', all the main features of the near-death experience were reported by the ketamine group under study here. All 36 participants were sure that what happened was real and not a mere 'hallucination' induced by ketamine. The accounts include visions of beautiful landscapes or peaceful environments where they met luminous divinities (30 per cent) as well as frightening sumi (with non-human faces), strange animals, and unknown or unseen presences (16.6 per cent). Some 16.6 per cent met dead relatives or friends. An interesting result in this sense was that all 36 visited a certain place, 'good' or 'bad'; 44.4 per cent described it as clearly mystical or unearthly. Events that happened 'there' were described with extreme clarity and accuracy even several years after the experiences.
Some 19.4 per cent felt surrounded by an unusual light of mystical or otherworldly origin. This has been described as 'bright', 'radiant', 'rather small', 'full of energy' and/or 'pure love and compassion', and 'vibrating sounds like mantras'. Two participants reported out-of-body experiences, which in both cases were unpleasant; 33.3 per cent were absolutely sure they left their bodies and that they temporarily existed outside them; 11.1 per cent were able to remember past events, while 16.6 per cent claimed that their past flashed out of control in front of them (the 'life review') and 52.7 per cent felt a total understanding of the universe, expressed in such statements as 'we originate from the source and relate to each other as if we were one big family'. Some respondents said that they had participated in the 'fabrication of the universe' or felt a 'cosmic union with earth', as if they were able to understand its constitutive principle by means of a principle within the self. One participant had birth-related memories, also known as near-birth experiences (NBEs). A small minority of the group reported extra-sensory perceptions. These included an enhanced level of telepathy and other apparent psychic abilities, such as precognition (including vision of the world's future reported by 16 per cent). A point or a border of no return was reached by 16 per cent.
In the following chapter, these results will be systematically compared with those obtained in a study carried out by Peter Fenwick on 36 subjects who reported NDEs as a result of either cardiac arrest or some other life-threatening circumstance. However, before proceeding to this comparison, a few remarks are necessary about the limitations of my study. This may be useful for those interested in conducting further investigations.
It is important to observe that not all ketamine users have experiences similar to near-death experiences. Currently it is impossible to predict who will have an NDE-like one. Those who took part in the study contacted me because they were willing to share their ketamine experiences. This may have overestimated the real occurrence of the near-death type of experience among ketamine users. Jansen, for instance, suggested that NDEs happen only to 12 per cent of ketamine users (Jansen 2001). This means that 88 per cent do not have one, and might not be aware of these effects. Another relevant observation is that according to those I interviewed, the NDE-like experiences were more likely to happen on first exposure to ketamine. Although further studies are required, this preliminary result suggests that it is not a recurrent effect. On the contrary, those who continued with consumption noticed that its NDE-like effects gradually faded away. Moreover, all the accounts that I collected inevitably dealt with memories of an experience and not with a direct experience. In this sense what has been called 'false memory' could play a role, especially when the memories were reported a long time after the event. For instance, this possibility is supported by results in experimental research, which have shown that eyewitness testimony is unreliable, including testimony of anomalous experiences (French 2005). An exemption to this observation is represented by those who reported an NDE as a result of a cardiac arrest and were interviewed immediately after the experience (e.g. Parnia et al. 2001; Sartori 2005). Furthermore, since most of the interviewees used other recreational drugs, one could ask if the NDE-like states they described were associated with the ketamine use or are more appropriately to be considered a result of ketamine/polydrug intake instead. One could also wonder if findings similar to those described here might have been observed for other psychoactive compounds (e.g., dimethyltryptamine; Strassman 2001). The present data would have been less difficult to interpret if they were the result of a prospective, double-blind vs placebo, study with volunteers who had no history of ketamine use. Although sometimes carried out (Krystal et al. 1994), prospective studies with psychotomimetic drugs can raise ethical concerns.
There were further potential sources of uncertainty in this study. The interviews were not carried out close to the time of the ketamine experiences, and so there was no possibility of employing toxicological tests to confirm the interviewees' statements about the drugs they had taken. It therefore cannot be ruled out that other drugs (e.g., cannabis) had recently been self-administered (Jansen 2001). Finally, participants often had great difficulties in articulating their experiences. Although some details can be described, the essence of these experiences is inexpressible and beyond thought: in one word, it is 'ineffable'.
Was this article helpful?