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Bruce Springsteen got it right: Love makes us dumb.
In "Crush on You" from The River album, he sings, “My brain takes a vacation just to give my heart more room.” As I have discussed in a previous post, when we are in love, our single-minded obsession with our lovers can impair other aspects of our intellectual lives, such as studying or working (van Steenbergen et al., 2014). Passionate love in particular is associated with reduced cognitive control — the ability to focus on one thing while ignoring distractions (van Steenbergen et al.). Further, when thinking about love (as opposed to sex or a neutral topic), we perform worse on analytical thinking tasks (Förster et al., 2009).
Researchers hypothesize that feelings of love, which stimulate the areas of the brain associated with reward, may also deactivate the areas of the brain associated with other cognitive functions (Wlodarski & Dunbar, 2014). However, although love impairs some cognitive skills, such as working memory and attention, the experience of love may improve neural functions such as identifying emotional states (Wlodarski & Dunbar) and creative thinking (Förster et al., 2009). This research involved mostly undergraduate students, so we can't be sure whether love will also make older adults dumber; increased social interaction is associated with better cognitive abilities in older adults (see Wright et al., 2017).
... but Sex Makes You Smart
Although it may not be surprising that love makes us dumb, you might be surprised to learn that sex may make you smarter. A variety of evidence shows that sexual activity is associated with better cognitive abilities in older adults (Padoani et al., 2000; Wright and Jenna, 2016; Wright et al., 2017). Older adults who remain interested in and engaged in sexual activity also retain stronger cognitive skills, such as verbal fluency, number sequencing, and recall.
Researchers posit that sex enhances the secretion of dopamine, which may then help to improve working memory and other cognitive skills (Wright et al.). However, because this research involved only older adults (typically 50 or older), we can't conclude that those of us under 50 will reap any benefits from enhanced interest in and participation in sex, but it probably couldn't hurt.
Further, because this research is correlational, we can't be sure whether increased sexual activity leads to better cognitive functioning, or whether better cognitive functioning leads to increased sexual activity. To determine a causal relationship, researchers would need to manipulate the frequency of sexual activity and then measure whether cognitive increases resulted from increased sexual activity. Before you rush to volunteer for this research, be aware that when couples are asked to increase the frequency of their sexual encounters, they actually show decreased happiness, as well as reduced enjoyment of sex (Loewenstein et al., 2015). So, would you rather be smart or happy?
Other experimental research does show that thinking about sex (versus love or a neutral topic) improves our analytical skills (Förster et al., 2009). However, thinking about sex in the presence of a potential partner tends to make us dumber. As discussed here, men’s performance on working memory and attention tasks declines after interacting with a beautiful woman, presumably because the men are preoccupied with thoughts of seduction (Karremans et al., 2009). However, some might suggest that if a man is acutely focused on working memory and attention tasks in the presence of a beautiful woman, he is the dumb one.
These associations among love, sex, and intellect are fascinating. As we look forward to more intriguing research on these topics, I hope we will all become both smarter and dumber.
Interested in learning more about sex and love? Check out our book, The Social Psychology of Attraction and Romantic Relationships, available via Amazon.
Portions of this post were taken from The Social Psychology of Attraction and Romantic Relationships. Copyright 2015 Madeleine A. Fugère.
References
Förster, J., Epstude, K., & Özelsel, A. (2009). Why love has wings and sex has not: How reminders of love and sex influence creative and analytic thinking. Personality and Social Psychology Bulletin, 35(11), 1479-1491.
Karremans, J. C., Verwijmeren, T., Pronk, T. M., & Reitsma, M. (2009). Interacting with women can impair men’s cognitive functioning. Journal of Experimental Social Psychology, 45(4), 1041-1044. doi:10.1016/j.jesp.2009.05.004
Loewenstein, G., Krishnamurti, T., Kopsic, J., & McDonald, D. (2015). Does increased sexual frequency enhance happiness?. Journal of Economic Behavior & Organization, 116, 206-218.
Padoani, W., Buono, M. D., Marietta, P., Scocco, P., Zaghi, P. C., & De Leo, D. (2000). Influence of cognitive status on the sexual life of 352 elderly Italians aged 65–105 years. Gerontology, 46(5), 258-265.
van Steenbergen, H., Langeslag, S. E., Band, G. H., & Hommel, B. (2014). Reduced cognitive control in passionate lovers. Motivation and Emotion, 38(3), 444-450. doi:10.1007/s11031-013-9380-3
Wlodarski, R., & Dunbar, R. M. (2014). The effects of romantic love on mentalizing abilities. Review of General Psychology, 18(4), 313-321. doi:10.1037/gpr0000020
Wright, H., & Jenks, R. A. (2016). Sex on the brain! Associations between sexual activity and cognitive function in older age. Age and ageing, 45(2), 313-317.
Wright, H., Jenks, R. A., & Demeyere, N. (2017). Frequent Sexual Activity Predicts Specific Cognitive Abilities in Older Adults. The Journals of Gerontology: Series B.
