A neuroscientist at Northeastern University is calling for medical testing not just to include female subjects, but to design experiments that better account for both biological sexes.
In an article published in Science, Dr. Rebecca Shanksy argues that experiments using male subjects as a default pose a public health problem. She explained to The New York Times that though the National Institutes of Health mandates that female subjects be included in all preclinical research, the problem is much deeper than that. In neuroscience studies, male subjects outnumber female subjects six to one, and are still tested separately with the male results usually being seen as standard:
“Dr. Shansky offered an example of how females were expected to behave in tasks designed to model post-traumatic stress in male rodents. Instead of freezing as males did, the females darted around during experimental tests. Without recognizing this behavior as different, rather than wrong, one might say females failed the task.”
The problem stems from generations of gendered ideas about male and female brains and stereotypes that categorize male brains as orderly and rational while female brains are messy, emotional, and hormonal. In recent years, these ideas have been challenged, but those challenges don’t mean much has changed, according to the Times:
“In recent years, analyses of hundreds of neuroscience studies offered clear evidence disproving the idea that males are less hormonal. In some cases, male rodents living in groups were messier because their testosterone (which essentially works on the brain like estrogen) fluctuates, depending on dominance hierarchies in groups.”
But even if those old stereotypes held true, that doesn’t mean that tests should be designed to discount an entire group, according to neurobiologist Daniella Pollak:
“Even if scientists had shown that females were more complex subjects, “‘it would not suffice as an excuse,’” said Dr. Pollak. “‘Scientists are not meant to give up on a problem just because it starts becoming complicated.’”
These mindsets have real-world repercussions. The article sites a 2013 Food and Drug Administration advisory that recommended women take a half dose of the sleep aid Ambien based on women reporting more side effects. However, it was later discovered that body weight was causing inaccurate dosing, resulting in overdoses for men and underdoses for women.
Correcting the problem, according to Shansky, means overhauling the siloed ways research has traditionally been conducted:
“Dr. Shansky [says] research can be improved by studying the sexes in parallel or in the same cohort, instead of experimenting on one sex after the other and making the first set of results the standard.”