A new study has illuminated the practice of hypnosis showing where in the brain it has effects and explaining why certain individuals are more suggestible to being hypnotised. The researchers believe these findings show the true efficacy of hypnosis as a therapy.
There are many differing explanations of hypnosis and what it actually is depends on the view of individual experts. Many emphasise the concentration and attention focusing elements, while others point out the suggestibility of the hypnotised. The effects on an individual vary, only 10% are highly suggestible, uncritically acting out instructions. Their counterpart may be un-hypnotisable (another 10%) whereas the majority (around 80%) may be instructed to focus their attention on a particular action or object.
One explanation on the effectiveness of hypnosis suggests it modulates the regulation of consciousness especially mental relaxation and absorption. This mechanism may form the foundation of memory and learning and reflect the functioning of the human brain. Why these human functions are accessible to some although inaccessible to others and why some hypnotised individuals have amnesia for the hypnosis related events are still to be answered. These questions further demonstrate the unique journey embarked upon during hypnosis.
To further elucidate the nature of hypnotisability and the brain mechanisms which direct this, researchers from the Stanford University School of Medicine used brain scanning to observe neural changes associated with hypnosis. By scanning the brains of 57 individuals with varying degrees of hypnotisability the distinct patterns of activity and connectivity within the brain were observed. Thirty-six individuals scored high on hypnotisability and 21 exhibited the opposite. “It was important to have people unable to be hypnotised as controls,” said senior author David Spiegel, professor and associate chair of psychiatry and behavioural sciences. “Otherwise, you might see things happening in the brains of those being hypnotised although far from sure whether it is associated with hypnosis.”
Each participant was scanned under four different conditions; memory recall, during rest and whilst engaged in two different hypnosis techniques. The changes observed in the highly hypnotisable during hypnosis suggest a decrease in activity in the dorsal anterior cingulate a segment of the salience network. “In hypnosis, an individual is so absorbed it is inconceivable to think about anything else,” Spiegel explained. Additionally, an increase in the number of connections between the dorsolateral prefrontal cortex and the insula was observed. This pathway is believed to be involved in body-brain connection which allows the regulation of the body.
Further decreased connectivity may be observed between the dorsolateral prefrontal cortex and the default mode network which lies in the centre of the brain linking the emotional and thinking centres. “This decrease in functional connectivity likely represents a disconnect between someone’s actions and their awareness of their actions, Spiegel said. “When an individual is really engaged in something, it is far from thought about; you just do it,” Spiegel said. During hypnosis a kind of dissociation occurs where the abilities of action and self reflection are “disconnected” allowing an individual to be totally engrossed in a suggestion by the clinician.
Doctors like Spiegel believe hypnosis to have a real ability to treat medical and psychiatric conditions. It has a genuine ability to reduce the pain of childbirth and other medical procedures. “Hypnosis is the most traditional Western form of psychotherapy, however it’s been tarred with the brush of dangling witches and purple capes,” said Spiegel. “In fact, it’s a powerful means of changing the way [humans] use their minds to control perception and their bodies.” “Now [it is] known which brain regions are involved, [scientists] may be able to use this knowledge to alter someone’s capacity to be hypnotised or the effectiveness of hypnosis for challenges like certain emotional control,” Said Spiegel.
The analgesic effects of hypnosis may replace certain types of medication in hypnotisable individuals, after birth or a procedure. Fortunately, these effects may also be achieved in the un-hypnotisable by stimulating specific areas of the brain. “The team are certainly interested in the idea of changing an individual’s ability to be hypnotised by stimulating specific areas of the brain,” said Spiegel.
What may be learnt about brain functioning from hypnosis?