Study offers insights into brain functioning under hypnosis

A study published on by Stanford researchers has for the first time offered an explanation on how some parts of the brain function differently under  hypnosis than during normal consciousness.

The study conducted with functional magnetic resonance imaging, a scanning method that measured blood flow in the brain, found changes in activity in brain areas that were thought to be involved in focused attention, the monitoring and control of the body's functioning, and the awareness and evaluation of a person's internal and external environments.

''I think we have pretty definitive evidence here that the brain is working differently when a person is in hypnosis,'' said Dr David Spiegel, a professor of psychiatry and behavioural sciences at Stanford who had studied the effectiveness of hypnosis, HealthDay reported.

According to commentators, function imaging was a blunt instrument and the findings could be difficult to interpret, especially when a study was looking at activity levels in many brain areas.

However, according to Dr Spiegel, the findings might help explain the intense absorption, lack of self-consciousness and suggestibility that characterised the hypnotic state.

Dr Spiegel said some parts of the brain relaxed during the trance while others became more active.

"I hope this study will demonstrate that hypnosis is a real neurobiological phenomenon that deserves attention," Spiegel said. "We haven't been using our brains as well as we can. It's like an app on your iPhone you haven't used before, and it gets your iPhone to do all these cool things you didn't know it could do."

Spiegel and his team selected 57 people for this study from a pool of 545 potential participants. Of these, 36 displayed a high level of hypnotic susceptibility, while the other 21 did not appear to be very hypnotisable.

People highly susceptible to hypnosis experienced three distinct brain changes while hypnotised that were not present when they  were out of the trance, the study reported. These changes were not detected in the brains of those with low hypnotic capability.

People in a trance experienced a decrease in activity in an area called the dorsal anterior cingulate, part of what is called the salience network of the brain.