PMS: Poor Memory Syndrome

High estrogen levels during menstruation may inhibit learning


By Joseph Castro | Posted October 5, 2010

Man, women have it hard.

Let’s forget about lower pay rates, and how some women will go through nine months of pregnancy and a painful childbirth.

Instead, let’s look at a woman’s closest companion: her period. (Yes, I’m a guy and I’m really talking about this.)

You probably already know about the side effects of menstruation (watch Chef’s take on South Park). However, you may not know about a recent study in rats that suggests the high levels of estrogen women experience while menstruating may interfere with their ability to learn during that, um, period.

Researchers at Concordia University compared the “latent inhibition” of rats with low estrogen levels to rats with high estrogen levels. Latent inhibition is believed to be an integral part of learning — it enables humans and some other species to better interact with their environments by ignoring irrelevant stimuli while developing important associations with relevant stimuli. To visualize it, think about your annoying younger brother and how he would constantly repeat your name until you entertained him. Now think about that wonderful moment when you were finally able to unconsciously ignore his calls as if he weren’t there. That’s latent inhibition at work.

In the study the rats were initially played a tone unconnected to stimuli. Once the rats became accustomed to the original tone and ignored it, researchers started playing another tone followed by electro-shock treatment. Turns out that the rats with high estrogen levels took longer to associate being shocked with the tone — their hormones actually decreased their latent inhibition and disrupted their ability to form new memories!



Author: Leslie Carol Botha

Author, publisher, radio talk show host and internationally recognized expert on women's hormone cycles. Social/political activist on Gardasil the HPV vaccine for adolescent girls. Co-author of "Understanding Your Mood, Mind and Hormone Cycle." Honorary advisory board member for the Foundation for the Study of Cycles and member of the Society for Menstrual Cycle Research.