Ketamine: Dreams and Realities
Ketamine, Near-Death, and Near-Birth Experiences
Dreaming There is some common ground between dreams, ketamine experiences, and near-death experiences, which can occur during sleep.509 In all of these states there is a reduced input from the outside world. There is some evidence that many of those who do not recall their dreams are also unable to recall ketamine journeys. In a study of 150 patients, 45% recalled dreaming at home.209 Of these home dreamers, 75% described having dreams during ketamine anesthesia (50 out of 68), while only 2 of the 82 patients who were not home dreamers had dreams during the anesthesia. This is a highly significant and fascinating result meriting further research. The percentage of home dreamers is the same as that reporting ketamine journeys in many anesthetic studies, about 40%, and also the same as the 40% reporting neardeath experiences when the widest possible definition of a NDE is used.512 A gene has been found which, it has been suggested, may account for why some persons with schizophrenia show a greater “psychotic” response to ketamine than others.377 Whether the status of this gene plays any role in explaining why some people have few psychedelic effects from the drug, while others have profound experiences, remains to be seen. Ketamine can sometimes produce rapid-eye movements (REM) and brain wave patterns like those seen during dreaming.143 Part of the
(“temporal lobe”) may result in a NDE.471, 511 The death of cells due to epilepsy results from excessive release of glutamate.451 This is likely to trigger the protective system discussed above, producing mental byproducts. Ketamine can be both anti-epileptic and pro-epileptic.524, 578, 586, 602 What it does may depend on the state of the nervous system it enters.341, 431, 603 It may calm the over-excited brain and over-excite the calm brain, producing excitement by switching off the inhibitory system.121
brain wave tracing made during sleep is called the K-complex, but this term is a coincidence. The K-complexes recorded during natural sleep and during ketamine experiences are the same.10 Sleep and dreaming involve the glutamate system and indirect blockade of N-P complexes.118, 142, 369
Epilepsy? Epilepsy is brain excitation that has escaped from the usual calming systems. Some types of epilepsy do not involve fits in which the person falls to the ground (i.e. “grand mal”). This type of epileptic fit
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An Endorphin Rush A flood release of natural opioids called endorphins may also contribute to the NDE.60 A sudden increase in endorphins was seen in the brain and body fluids of dogs that were conscious at the moment of death.562 However, endorphins are unlikely to produce a NDE on their own. They are not usually classified as psychedelic drugs although they are occasionally linked with feelings of euphoria, such as the “high” that sometimes results from running. Injection of betaendorphin into people has pain-killing effects but does not usually result in seeing God.461 Nevertheless, ketamine can also release betaendorphin,169 there is cross-talk between the glutamate and opioid systems,32, 53, 627 and ketamine can activate the kappa opioid receptors217 that have long been suspected of playing a role in producing some psychedelic effects.474 Beta-endorphin probably does play a role in both NDE and ketamine effects, but it is not the lead actor.
Low Oxygen/High Carbon Dioxide When the blood supply is cut off, brain oxygen levels plunge and carbon dioxide levels soar. Studies involving a gradual fall in oxygen reported the effects as little more than mental clouding.211 However, these studies are not an accurate model of events in cardiac arrest (for example) where there is a sudden fall in oxygen levels. As discussed previously, this is known to cause a glutamate flood that can in turn trigger the process leading to a NDE in some people.
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