HACKER Q&A
📣 mettamage

Are there scientific underpinnings for hypnosis?


I know what I'm asking, there's not a lot on HN about hypnosis. To the extent I've researched it myself (10 years ago), all I've seen is pseudoscience. But when I see stage performances like this [1], I can't help but think "well, clearly this works on a small subset of people!" One might argue, that the trick is to get highly suggestible people on there. That's why it works. I suspect it's that simple (it could be that simple, I simply don't know, I am quite clueless). Perhaps more importantly, it could be researched if suggestibility is the only factor at play here [2, 3].

When I look at videos like [1], I clearly see problems with the explanation of hypnosis. It is apparently the same as REM sleep, yet no studies were cited. I mean, it sounds plausible, but a lot of things sound plausible (true and untrue things). In other words, hypnotists aren't scientists. When it comes to the human mind, the best scientific role we have are psychologists.

Did anyone on HN do some research on this? I'm asking you, because I'm dreading that Google would show me 10 websites with nonsense for every 1 website that has a small scientific result.

My own first pass yields (via scholar.google.com):

- VR and hypnosis (both effects seem to be independent, more research needed): https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7247604/

- Hypnosis reduces pain: https://research.gold.ac.uk/id/eprint/25841/1/Thompson%20et%...

- Myths about hypnosis: https://research.gold.ac.uk/id/eprint/29294/1/Lynn%20et%20al...

My (perilous) pass on YouTube yielded:

- SciShow talking about hypnosis: https://www.youtube.com/watch?v=RWMYNTnoEyQ (the Stroop test differences sound like compelling evidence, because that's performance-based)

[1] https://www.youtube.com/watch?v=1RA2Zy_IZfQ

[2] IMO such a thing should've been researched, wouldn't it? If I'd get a week, I could design a half decent experiment myself. The gist: get a control group and a normal person claiming to be a hypnotist. Get an experimental group with an actual hypnotist. The normal person performs a routine of whatever he/she believes is hypnosis, the hypnotist does the same thing. The only difference between the two should be how long they've studied hypnosis (preferably 0 seconds -- other than having seen a stereotypical depiction of it -- vs 10+ years). Then there's the "hypnotized group" in both conditions. Let this group perform certain tasks that one could rate on performance (cognitive tasks, acting tasks, the whole gamut). Video tape all of this. Get raters that need to classify and rate the tasks done on the video on a 1 to 5 scale based on performance or "most accurate". Calculate inter-rater reliability to see if people have quantified tasks and performance metrics similar enough. See if there's a big difference. I don't mean a p < 0.05 difference, no a big one. It should be clear that the hypnotist clearly brings something out in a subset of the audience where as the fake hypnotist clearly has little clue what he/she is doing with similar highly suggestible people.

Thinking about it now, I'd probably just recruit highly suggestible people. The way I'd do that is to get an independent hypnotist (that isn't part of any condition) and let him/her figure out who's highly suggestible for hypnosis, split that group in two for the control and experimental condition (matched on age, gender, etc.). This is why I'd need a week to get a half-decent design. It's been a while :P

If there are, then it's easy to isolate that hypnosis isn't just filtering out highly suggestible people. It simply suggests that it's one of the tricks they apply, but what are the other tricks?

[3] I've experienced a thing or two with meditation that seem to be related. Whenever I meditated getting into a trance or whatever they call it was never ever the point. Yet, I've been in emotional states that were very unusual and interesting. I experienced the same thing with exercise. So it seems plausible that more could be going on (but IMO that's not enough evidence, scientific research is needed).


  👤 PaulHoule Accepted Answer ✓
Hypnosis is the placebo effect. I would point you to the old book persuasion and healing by Jermone Frank. For most of human history the first line treatment for any medical condition has been faith healing, which works better than doing nothing.

Hypnosis as a state has been elusive and hard to prove, hypnotic phenomena seem to be more real. One viewpoint is that the ‘hypnotized’ person is ‘pretending to be hypnotized’, that it really is some combination of role-playing, daydreaming, etc.


👤 codeptualize
You might be interested in EMDR. There is still lots of debate on it, but it's used in psychology and you might find some actual research.

I don't think it has much to do with stage hypnosis though, which I would say is just entertainment. Similar to spoon bending, fortune tellers, mediums and similar. It's an illusion.


👤 mettamage
More stuff I found:

- a neuroscience paper on hypnosis: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6248753/ (from a Tim Ferriss video where he interviews Dr. Andrew Huberman ).