I must begin this blog post by acknowledging I am not a neuroscientist and that I do not write this post as someone professing to have all the answers to questions about the effects of hypnosis on the body. Instead I write as someone interested in what might be the physiological reaction of the body to hypnosis, based on relevant (linked) research in the field. I hope the post works as a starting point for consideration of self-hypnosis as a potential tool in management of physiological conditions.
But before I get on to the opportunities that hypnosis may or may not present, I should define ‘hypnosis’. It has been defined variously as an altered state of consciousness, a wakeful sleep and strongly suggestive state, but the definition I prefer is ‘mega-placebo’.
While this last is a term generally used by skeptics of the value of hypnosis, it does accurately articulate the outcome of hypnosis. In drug trials, a placebo effect is a marked response to an inert substance, in line with what the patient is told the drug will be able to achieve. Fascinatingly, the effect is not always perceptual. Historically it has been used in medicine as a means of maintaining health and managing pain, and even currently, the assurance of an authority figure can reduce stress and pain. It has been posited by many critics (Oliver wendell Holmes among many others) that the efficacy of many homeopathic and alternative medicines is largely placebo. But what is important is that regardless of whether the actual ingredients of homeopathic medicines are active or inert, their positive effects can be observed not merely perceptually, but often physiologically.
During hypnosis, regardless of whether subjects are actually conscious or in a form of trance, they are voluntarily entering a deep relaxation state, and in this state, either through the instrument of a hypnotherapist or through their own deep concentration, they are able to absorb suggestions – in the manner of a placebo effect – and on emergence from a hypnotic state, demonstrate remarkable mental or physiological responses to ideas presented under hypnosis. (See clinical trials literature on hypnosis as a tool in smoking cessation, depression treatment, and pain reduction.)
Recent neuroscience experiments using hypnosis have dealt with colour perception, and MRI brain imaging has identified that in a post-hypnotic state, highly hypnotizable subjects were able to overcome ‘natural’ conflicts in the brain and brain activity altered during a testing exercise. (For details of the experiment see the New York Times description.)
Thus there is clear clinical evidence of the mega-placebo, suggestion-receptive effects of hypnosis on up to 80% of any population. (And there is strong evidence that even among so-called ‘non-hypnotisable’ people, it is still possible to induce a placebo effect through conscious suggestion.)
Technically what appears to be happening in hypnosis is that the balance of chemical neurotransmitters such as serotonin and dopamine change dramatically both during hypnosis and afterwards, the latter apparently as a direct response to suggestions during hypnosis. The act of entering hypnosis, often induced through calming, meditative practice appears to increase serotonin levels (feel-good, inner peace neurotransmitters) and this primes the brain for acceptance of hypnotic suggestion, whilst dampening conflict responses. At the same time, dopamine levels (alertness, excitation neurotransmitters) are reduced. After hypnosis, dopamine levels rise, but depending on hypnotic suggestion, reuptake of serotonin may be inhibited.
Importantly, this is precisely the chemical reaction that takes place with the use of most bulk standard anti-depressants (SSRIs). Now I’m not in any way suggesting that hypnotism should be used instead of anti-depressants for treatment of chronic depression or dysthymia, as the effect of hypnosis is much less marked than is demonstrated with the use of SSRIs. But the primary difference between use of anti-depressants and hypnosis is that the effect of hypnosis is actually a memory or suggestion-triggered response, and not a largely chemical one as with the use of SSRIs. Mega-placebo it may be, but perhaps the greatest aspect of hypnosis is in perception alteration through manipulation of neurochemical responses.
My hypothesis is that hypnosis is actually a highly specialised, pathological form of learned behaviour. Through concentrated relaxation techniques, humans have the capacity to influence their own biological and neurochemical reactions through suggested/learned/remembered problem solving. While the effects are limited, it may be possible to use hypnosis to ‘train’ the brain to emulate the effects of drug treatment, or respond to physical injury, learning/business challenges and personal/personality problems – all through moderation of neurotransmitter levels and triggering of other biochemical responses.
If this is truly possible, it would go some way to explaining the feats of endurance or pain inhibition demonstrated by various athletes, gurus, swarmis and circus performers around the world. But more importantly, hypnotically mediated neurochemical manipulation could provide medicine with some serious options for management of both physical and mental pain.
Deeper into the neuroscience of hypnosis:
Hypnotic suggestion and cognitive neuroscience:
Science finally tackles hypnosis:
Pain management for outpatients: