By Dr. Justin Lehmiller
A series of recent studies suggests that frequent sexual activity could potentially benefit the brain.
First, a 2010 study on male rats discovered a link between sexual activity and neuron growth [1]. Specifically, rats that had daily sex for two weeks demonstrated more neuron growth than rats that were only allowed to have sex once during the same amount of time. Following this, a 2013 study—which also focused on male rats—found that daily sexual activity was linked not only to generating more new neurons, but also to enhanced cognitive functioning [2].
While these findings imply that sex may be good for the brains of rats, what about humans? A recent study published in the Archives of Sexual Behavior provides evidence that sex could potentially be good for our brains as well [3].
In this study, researchers surveyed 78 heterosexual women aged 18-29 about their frequency of penile-vaginal intercourse. These women then completed a common memory task. Specifically, they were shown a series of faces and abstract words (such as “chastity”), which they were then asked to memorize. Later on, participants were given a list of faces and words, some of which were from the memorization task and others that were brand new. Participants then had to report whether each face/word they saw was old or new.
Researchers then looked to see whether intercourse frequency was linked to memory while controlling for several other variables, including grade point average, menstrual cycle phase, oral contraceptive use, and relationship length. In turned out that women who had sex more often had better recall of abstract words; however, there was no link between intercourse frequency and recall of faces.
Why was intercourse frequency specifically linked to verbal memory but not facial memory? The authors believe it’s because memory for words is a function of the hippocampus, a structure deep within the brain. This is the same structure where neuron growth was identified in the above-mentioned studies of male rats. Memory for faces, they argue, depends more on structures outside the hippocampus, which could potentially explain these discrepant findings.
Another recent study focusing on older adults provides additional support for these conclusions [4]. Among adults aged 50-89, frequent sexual activity (defined broadly so as to also include activities other than intercourse) was linked to enhanced recall on a memory task. Both men and women were included in this study, and the sex-recall association did not depend on gender.
Of course, it’s important to note that both of these were correlational studies, meaning we cannot infer cause-and-effect. To have confidence that sex does indeed improve human memory, we really need randomized, controlled experiments (not unlike the aforementioned rat studies) in which participants are instructed to have more or less sex. Alternatively, a longitudinal study in which people give daily reports on their sexual activities and complete a memory task at the end could also offer valuable insight.
Though we must await further research to learn more, the current evidence suggests the provocative possibility that having sex just might be a smart thing to do.
References
[1] Leuner, B., Glasper, E. R., & Gould, E. (2010). Sexual experience promotes adult neurogenesis in the hippocampus despite an initial elevation in stress hormones. PLoS One, 5(7), e11597.
[2] Glasper, E. R., & Gould, E. (2013). Sexual experience restores age‐related decline in adult neurogenesis and hippocampal function. Hippocampus, 23(4), 303-312.
[3] Maunder, L., Schoemaker, D., & Pruessner, J. C. (2016). Frequency of Penile–Vaginal Intercourse is Associated with Verbal Recognition Performance in Adult Women. Archives of Sexual Behavior.
[4] Wright, H., & Jenks, R.A. (2016). Sex on the brain! Associations between sexual activity and cognitive function in older age. Age and Ageing.
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Dr. Justin Lehmiller is an award winning educator and a prolific researcher and scholar. He has published articles in some of the leading journals on sex and relationships, written two textbooks, and produces the popular blog, Sex & Psychology. Dr. Lehmiller’s research topics include casual sex, sexual fantasy, sexual health, and friends with benefits. He is currently the Director of the Social Psychology Graduate Program and an Assistant Professor of Social Psychology at Ball State University.