Period 30: A long overdue newsletter, must be my cycle-driven white matter microstructure changes
Phew, I’m back! I’m sure you missed me. I’m desperately trying to finish three chapters of the book simultaneously (which is a terrible idea by the way) which means my brain is constantly occupied with thoughts of pregnancy loss and I’m struggling to transition to anything else.
Like answering important emails, finishing two overdue service projects, and regularly putting out this newsletter. I fee like the turkey in Sandra Boynton’s Blue Hat, Green Hat, which my youngest has been requesting a lot lately because she is learning to read and there are lots of sight words in there she knows.
Oops.
I gave three talks last week. The one that was recorded, and will be up by the end of the semester with transcription, was for a Wenner-Gren Foundation Workshop on Socio-political Knowledge Production in Anthropology. In less academic speak, what we talked about over four days of talks and panels and discussion groups were issues of practice and process in science. We discussed how we produce knowledge, how we disseminate it, the incentive structures that lead to certain kinds of publications, and more. My talk was on our vaccine and menstrual changes project, BLEEDVAX, and it was titled “Feminist anthropology: emergent methodologies as acts of noticing.” I’ll share when it’s up! Talks were only 20 minutes each so it’s a great way to dive into these topics if you’re curious.
Links
On the Israel-Gaza war and manufactured consent. I’ve read a lot of takes over the last few weeks, watched a lot of video of people on the ground, seen a lot of people equate any support of Palestinian life as implicit support for Hamas’s terrorism, and seen even more say even the gentlest critiques of the Israeli state is anti-semitic. I recommend this piece.
I look forward to watching this documentary on Black landownership when it starts streaming on Prime in December. Read about Silver Dollar Road.
I encourage you to read this deep dive into what The Epoch Times is, who funds it, and their lack of journalistic integrity.
Another longform piece on the cycle syncing trend, this time from The Cut. A good pull-quote to give you a sense of one (of many) critiques of this trend:
“But beneath the merely specious claims lurk more insidious ones. Though Vitti pays lip service to inclusivity (if people — say, cis women who’ve had a hysterectomy, or trans women — are interested in cycle syncing but don’t get a natural period, they can try aligning their activities with the phases of the moon, she offers), her work traffics in biological essentialism, holding up the “natural” hormonal cycle as the epitome of womanhood and the locus of feminine power.”
I would argue the other big critique (again of many) to make against cycle syncing is it assumes we should only change our physical activity with our perceived changes in energy. Instead, I’d argue that when we have lowered energy we should EAT MORE FOOD. However the way fat phobia works means people who menstruate are infrequently encouraged to nourish their bodies, and often unlearn how to pay attention to hunger signals. That’s why you end up having this encouragement of moving less rather than just, say, grabbing an extra bowl of cereal that day. If we agree that endometrial proliferation takes some extra calories, maybe your body just needs a little more carb to fuel that tissue growth.
And of course, what would this newsletter be if I did not remind you the pandemic is ongoing. Please read Arijit Chakravarty and Martha Lincoln’s piece in The Nation on current messaging about covid as well as what’s actually happening right now, as well as a smart look back at previous times we’ve been told covid is nothing to worry about. Wastewater levels are still high folks. Mask up and get your boosters (and look into Novavax as a possible contender for a longer term solution – we don’t have the data yet, to be clear, but there’s some thinking it may do better to stop transmission than the mRNA vaccines).
Weekly period fact (no longer weird because it started to feel pathologizing to call it weird even though I was trying to invoke the “try this one weird trick” meme)
Do brain structures or other brain elements vary through the menstrual cycle? Maybe! My friend Tara Haelle just sent along this reported piece on a new preprint on the topic. The study authors performed MRIs of the brains of 30 naturally cycling (meaning, no hormonal contraception or treatments) premenopausal people three times in their menstrual cycles: during menses, around ovulation (typically peak estrogen), and in the mid-luteal phase (that’s typically peak progesterone if the person ovulated).
Some methodological caveats: participants were young, 18-29 years with an average age of 21 years. People don’t typically achieve peak hormone concentrations until they are in the 25-35 age range and my (admittedly-not-a-neuroscientist) understanding of brain development is that adult brain development isn’t achieved until 25-ish either.
And some methodological appreciations: I was really glad to see that the study authors used LH test strips to determine ovulation – not a lot of studies bother to do that and just assume the periovulatory period is “around” midcycle. Yay! This also means the mid-luteal timing is more trustworthy. I love a good method that understands menstrual cycles.
So what did they find? That across these three time points they could see changes in the microstructure of white matter, of cortical thickness, and of changes to brain volume – and these changes were associated with measured changes in ovarian hormones and gonadotropins (those are LH and FSH). You can check out the reported piece and the paper to see more of a discussion of this, but what I want to focus on is that this is one of the reasons it’s so important we study the menstrual cycle. The body responds to things that happen in the ovaries and the uterus throughout the premenarcheal, premenopausal, and even peri- and postmenopausal periods, things that are worth knowing. Do they rise to the significance of creating changes to cognition, mood, or anything else? I’m not sure we know that yet!
Of course, the other question I’d have is how testosterone, which fluctuates massively among the testes-havers over the course of EVERY DAY rather than ovarian hormones that fluctuate over the course of a month-ish, affects brain microstructures, cortical thickness, and brain volume.
Source: Rizor, E. J. et al. Menstrual cycle-driven hormone concentrations co-fluctuate with white and grey matter architecture changes across the whole brain. 2023.10.09.561616 Preprint at https://doi.org/10.1101/2023.10.09.561616 (2023).
*A preprint is a paper that has been put on a special archive in advance of peer review. The peer review process can be long and so increasingly people are putting their unedited papers on these archives (my lab included!) in order to 1) stake a claim around the work to avoid being scooped while waiting on peer review, and 2) create free, open access versions of these papers accessible to the wider public. The limitations of course are that the papers are not yet peer-reviewed and you need to pay attention to updates/whether and when the paper actually gets published because the first version you read may not be the final version.