Discover the science behind hypnosis, how it’s used to alter behaviour and even assist in surgery

Words by Scott Dutfield

It makes for some lighthearted entertainment when a group of willing volunteers walk on stage and stare blankly at a swinging pocket watch before remarkably transforming into a group of clucking chickens, but is hypnosis more than just a stage show?

Hypnosis is by no means a modern-day technique, with the first recorded medical use described in the Egyptian Ebers Papyrus, which was written in about 1550 BCE. Over time the skill of sending people into a deep trance has evolved to tap into the subconscious and implant suggestions to change addictive behaviours or treat ailments.

However, much like many other aspects of how the brain works, scientists remain relatively baffled by the phenomenon of hypnosis. It is collectively understood that its success is based on a person entering a heightened state of relaxation and focus through verbal and visual guides, at which point it’s believed that our brains are more susceptible to suggestion. There are two main theories as to why this works and what it does to our brains. Altered-state theory explains that hypnosis is much like sleep in the sense that when in a trance-like state the brain’s processes work differently, although you are not awake to acknowledge them. The non-state theory suggests that a hypnotised person is still aware of what’s happening, unlike when you’re asleep, and they are actively participating in the hypnotist’s instructions. However, there is still some debate and uncertainty behind which theory is correct.

So how do you become hypnotised? In a nutshell, a hypnotist or hypnotherapist ‘induces’ a person into a state of relaxation using verbal suggestion, typically using some sort of sleep analogy. After placing more and more emphasis on their imagination about something that is not in their real environment, a person begins to enter into a hypnotic state. However, not everyone is susceptible to hypnosis. A person’s ‘hypnotisability’ can range from them being completely immune and unresponsive to any hypnotic technique to a small percentage of the population being highly hypnotisable and susceptible to suggestion. Those that are highly responsive to hypnosis have shown that the technique can be used during surgery. Some patients have even been known to respond to posthypnotic suggestions, whereby an instruction will be given for an action to be carried out years later.