In November 2022, Aella posted this Twitter poll:

19% of women without post-menstrual symptoms believed in the supernatural, compared to 39% of women with PMS. I can’t do chi-squared tests in my head, but with 1,074 votes this looks significant. Weird!

Here’s another one:

Now 72% of people with PMS self-describe as neurotic, compared to only 45% without. Aella writes more about this here, and sebjenseb confirms here. I’m less weirded out by this one, because you can imagine that people feel neurotic because of PMS symptoms, but it’s still a surprisingly strong effect.

I tried to replicate this on this year’s ACX survey, using these questions:

These are a numerical scale, compared to Aella’s Y/N, so to start I dichotomized them: “have PMS” was defined as a score of 3+, and “believe in supernatural” was 2+. I freely admit these were post hoc choices intended to capture as much variation as possible. I selected for cis women only, to avoid any confounds with hormones and whatever trans people’s menstruation situation is:

30% of those without PMS believed in the supernatural, compared to 48% of those with symptoms. Chi-square was significant at the < 0.001 level.

55% vs. 61% anxious, chi-square was 0.046.

Going back and disaggregating the data, we find:

T-tests find both of these are significant:

Weird!

I asked Aella why she even thought to do a poll on this. She said:

I read the penis thieves book and figured if PMS is psychosomatic, this must be something around culture telling women they should feel bad around their periods, and women who are more susceptible to internalizing this to the degree they feel something real, might also be susceptible to internalizing other beliefs to the degree that they have a legitimately altered experience.

Sebastian proposes the alternative possibility that it’s something about hormones.

I tried correlating PMS symptoms with lots of other things I had to see what turned up. This is bad practice and for exploratory purposes only, but here’s what I found:

No correlation with any political opinion (there was a slight, likely random correlation with YIMBYism, not included on this table). Correlations with feeling negatively affected by various scary things, potentially related to neuroticism. Some correlations with what appears in their dreams (???). I didn’t have a big enough sample to do much work with psychiatric conditions.

This maybe slightly contradicts a suggestibility hypothesis (lots of people say Donald Trump is bad; wouldn’t that convince more suggestible people that Donald Trump is bad?). But also, on many questions where men and women differ (for example, on wokeness, not pictured on the table), there was no PMS effect. Maybe that argues against hormones?

I had two other questions about conditions which sometimes get classified as psychosomatic:

…but neither of them are correlated with PMS.

I’m pretty confused by this whole area.

As always, you can try to replicate my work using the publicly available ACX Survey Results. If you get slightly different answers than I did, it’s because I’m using the full dataset which includes a few people who didn’t want their answers publicly released. If you get very different answers than I did, it’s because I made a mistake, and you should tell me.