My current understanding of how hypnosis works is:
The overwhelming majority of our actions happen automatically, unconsciously, in response to triggers. Those can be external stimuli, or internal stimuli at the end of a trigger-response chain started by an external stimulus. Stimulus-response mapping are learnt through reinforcement. Examples: walking somewhere without thinking about your route (and sometimes arriving and noticing you intended to go someplace else), unthinkingly drinking from a cup in front of you. (Finding and exploiting those triggers is incredibly useful if you have executive function issues.)
This “free won’t” isn’t very reliable. In particular, there’s very little you can do about imagery (“Don’t think of a purple elephant”). Examples: advertising, priming effects, conformity.
Conscious processes can’t multitask much, so by focusing attention elsewhere, stimuli cause responses more reliably and less consciously. See any study on cognitive load.
Hypnosis works by putting you in a frame of mind where cooperation is easy; that’s mostly accomplished by your expectation to be hypnotised. For self-hypnosis you’re pretty cooperative already (“I am doing that, therefore it works and it’s good.”), otherwise rapport with the hypnotist and yes sets (consenting to hypnosis, agreeing to listen/sit/look at something, truisms) help. Inducing trance seems to be mostly a matter of directing attention elsewhere while preserving this frame of mind. Old school hypnotists liked external foci like swinging pocket watches, candle flames and spirals; mindfulness inductions work similarly; Erickson was fond of pleasant imagery; I’m partial to thinking about the process of hypnosis itself.
Modern writers tend to use “trance” to mean a highly suggestible state, whereas older ones just mean a state where you act on autopilot. Flow is the latter kind of trance but not the former, as the thing you’re concentrating on does prompt you to take some actions (“play these notes”) but not in any form that resembles suggestion. I’m less certain about this than about the rest of my model, the link between trance and suggestibility might be deeper.
So the evolutionary explanation for hypnosis would look something like this:
It’s easier to build a reflex agent than a utility maximiser, so evolution did that.
However, conscious decision-making does better, especially if you’re going to be all technological and social, so evolution added one on top of the preexisting connectionist idiot.
It is easily disrupted, because evolution is a complete hack and only builds things that are robust as long as you don’t do anything unusual.
My current understanding of how hypnosis works is:
The overwhelming majority of our actions happen automatically, unconsciously, in response to triggers. Those can be external stimuli, or internal stimuli at the end of a trigger-response chain started by an external stimulus. Stimulus-response mapping are learnt through reinforcement. Examples: walking somewhere without thinking about your route (and sometimes arriving and noticing you intended to go someplace else), unthinkingly drinking from a cup in front of you. (Finding and exploiting those triggers is incredibly useful if you have executive function issues.)
In the waking state, responses are sometimes vetted consciously. This causes awareness of intent to act. Example: those studies where you can predict when someone will press a button before they can.
This “free won’t” isn’t very reliable. In particular, there’s very little you can do about imagery (“Don’t think of a purple elephant”). Examples: advertising, priming effects, conformity.
Conscious processes can’t multitask much, so by focusing attention elsewhere, stimuli cause responses more reliably and less consciously. See any study on cognitive load.
Hypnosis works by putting you in a frame of mind where cooperation is easy; that’s mostly accomplished by your expectation to be hypnotised. For self-hypnosis you’re pretty cooperative already (“I am doing that, therefore it works and it’s good.”), otherwise rapport with the hypnotist and yes sets (consenting to hypnosis, agreeing to listen/sit/look at something, truisms) help. Inducing trance seems to be mostly a matter of directing attention elsewhere while preserving this frame of mind. Old school hypnotists liked external foci like swinging pocket watches, candle flames and spirals; mindfulness inductions work similarly; Erickson was fond of pleasant imagery; I’m partial to thinking about the process of hypnosis itself.
Modern writers tend to use “trance” to mean a highly suggestible state, whereas older ones just mean a state where you act on autopilot. Flow is the latter kind of trance but not the former, as the thing you’re concentrating on does prompt you to take some actions (“play these notes”) but not in any form that resembles suggestion. I’m less certain about this than about the rest of my model, the link between trance and suggestibility might be deeper.
So the evolutionary explanation for hypnosis would look something like this:
It’s easier to build a reflex agent than a utility maximiser, so evolution did that.
However, conscious decision-making does better, especially if you’re going to be all technological and social, so evolution added one on top of the preexisting connectionist idiot.
It is easily disrupted, because evolution is a complete hack and only builds things that are robust as long as you don’t do anything unusual.