Not only does sex feel good, but countless health benefits indicate that having sex is good for you, too. So it makes sense to assume having a lot of it can be advantageous. At least, that's what new research out of Canada suggests. According to a study published earlier this month in Archives of Sexual Behavior, frequent penile-vaginal intercourse (PVI) may have a positive effect on young women's memory.
Researchers out of McGill University were inspired to investigate whether having a lot of sex was associated with increased neurogenesis (or growth of nervous tissue) in the hippocampus, thus yielding better memory performance, after reading a slew of animal studies with similar findings. They recruited 78 heterosexual women under the age of 30 to participate in their study. In addition to undergoing a memory assessment viewing faces and abstract words, participants filled out a questionnaire inquiring about GPA, use of oral birth control and sexual behaviors, among other things.
When researchers analyzed the memory scores against all of the factors listed on the questionnaire, they found that PVI frequency was positively associated with memory scores for abstract word sensitivity scores, but not so for faces. "We can interpret this observation," the study's authors write, "as a sign that the relationship between frequency of sexual intercourse and abstract word sensitivity is indeed associated with a hippocampus-dependent memory function." They suggest the ability to retain faces, though, may lie within surrounding structures of the memory center and therefore unaffected.
Notably, it's unclear whether achieving orgasm affected memory. The analysis showed that "[f]requency of orgasm achievement during PVI was not significantly associated with abstract word sensitivity scores for women who were taking oral contraceptives," but the regression model was significant for those who were not on birth control.
Researchers also point out that relationship status had little impact on memory scores. "Thus, those single women who self-reported a high frequency of sex demonstrated higher memory scores than those coupled women who self-reported either not having sex or having a low frequency of sex," they write. "This suggests that it is PVI, and not the presence of a relationship, that accounts for the beneficial effects found in this study."
The study offered a handful of reasons why frequent PVI might be associated with memory for abstract words. One obvious explanation is that sexual intercourse is a form of exercise, and numerous studies have shown a relationship between physical activity and enhanced cognition. Another possible reason is that sex is known to help with depression and stress, both of which have been found to impair memory function.
Another possibility, the study offers, has to do with the "reward aspect" of sex. Jens Pruessner, a psychology professor at McGill University and one of the authors on the study, explains: "The chemicals involved with signaling reward to the brain—hormones and neurotransmitters—have also been shown to be associated with both memory and sexual activity. Thus, you can indeed speculate that both are associated with reward."
Pruessner cautions that it's still too early to understand the impact of their research. "Since the study just came out," he tells Broadly, "all we can say at this point in time is that we have made an observation between self-reported sexual behavior and measured cognitive function that is correlational, which means we can't say anything about cause and effect."
They can't offer any firm conclusions about what caused the increased memory function in the women they tested, he says, but future studies might do well to investigate how varying amounts and types of sexual behavior impact memory function.
In other words: Is it possible to have too much of a good thing?