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People make assumptions about men’s personality traits and behaviors based on pictures of their genitalia, according to new research published in Sexuality & Culture. The study found that positive personality traits tend to be associated with wider and longer penises with trimmed pubic hair. Narrower and shorter penises, in contrast, are associated with neuroticism.
“This topic really came out conversations with single colleagues and friends who were going through online dating and exchanging explicit media over apps and other messaging services,” said study author Thomas R. Brooks (@TBrooks_SexPsy), an assistant professor of psychology at New Mexico Highlands University and author of “CAPE: A Multidimensional Model of Fan Interest.”
“When one of their potential hook ups would send a picture of themselves, my friends would joke around about their qualities as a lover, their potential personality, and what it would be like to be with them. Carpenter (2022) calls this process: imagined interactions. I wanted to break it down and see if I could look at how explicit media contributed to this process of mate selection in digital spaces.”
In the study, 106 (mostly female) college students viewed 24 pictures of penises that varied in girth, length, and amount of pubic hair. The pictures were collected from publicly available reddit forums. After viewing each picture, the participants were asked to respond to eleven questions:
1. This is a prototypical/stereotypical penis.
2. This is an attractive penis.
3. This person is sexually active.
4. This person would be good in bed.
5. This person is extraverted, enthusiastic.
6. This person is dependable, self-disciplined.
7. This person is anxious, easily upset.
8. This person is open to new experiences, complex.
9. This person is sympathetic, warm.
10. Would this person be an active member of sex (pleaser) or a passive member in sex (pillow princess)?
11. How many sexual partners do you think this person has had?
The researchers found that differences in male genitalia were associated with different assumptions about personality. Penises seen as more prototypical/stereotypical were viewed as more attractive. Prototypicality was also strongly associated with being good in bed, conscientiousness, being sexual active, agreeableness, and openness to experiences. Prototypicality was moderately associated with neuroticism and being a “pleaser.”
In terms of girth, men with narrow penises were perceived to be more neurotic. Those with wide penises, on the other hand, were perceived to be more sexually active, better in bed, more extraverted, more open to new experiences, more of a pleaser, and to have had more sexual partners.
Regarding length, short penises were associated with more neuroticism than long or medium penises. Those with long penises were viewed as more attractive, more sexually active, better in bed, more extraverted, more conscientious, and more open to new experiences compared to their shorter counterparts.
“I think the big takeaway from this study is that people are being judged and assessed when they share pictures of their genitals,” Brooks told PsyPost. “However, the story is so much more than just ‘big penis = good.’ What we found was that the picture of a penis contributes to the implicit theory about that person, which includes assumed personality, behavior, and other attributes. When you send a picture, you are giving that other person more material to make assumptions about you.”
But how important is pubic hair? “I think I was most surprised by how public hair plays a role in impression formation,” Brooks said. “Both fully shaved and not trimmed at all were both seen as negative; there seems to be a happy medium when it comes to manscaping.”
Men with long pubic hair were perceived as less extraverted, conscientious, agreeable, and open to new experiences, compared to the trimmed and no pubic hair penises. They were also perceived as having the smallest number of sexual partners. Those with trimmed pubic hair, in contrast, were perceived as more attractive, sexually active, better in bed, and more of a pleaser compared both the long and completely shaved counterparts.
The results were similar regardless of gender or sexual orientation. But the study, like all research, includes some limitations. For example, the penises were all Caucasian and circumcised.
“In terms of caveats for the study itself, I think it would be helpful to increase the racial diversity and circumcision status of the penises,” Brooks said. “So, one aim of a follow up study would be to look at how race and circumcision interact in penis perceptions. I would also like to explore how unsolicited and solicited penis pictures might be viewed differently.”
The study, “Personality and Sexual Perceptions of Penises: Digital Impression Formation“, was authored by Thomas R. Brooks and Stephen Reysen.
