This mental trait predicts individual differences in kissing preferences

A new study published in Sexual and Relationship Therapy provides evidence that a person’s tendency to engage in sexual fantasy influences what they prioritize in a romantic kiss. The findings suggest that the mental act of imagining intimate scenarios is strongly linked to placing a higher value on physical arousal and contact during kissing. This research helps explain the psychological connection between cognitive states and physical intimacy.

From an evolutionary perspective, researchers have proposed three main reasons for romantic kissing. The first is “mate assessment,” which means kissing helps individuals subconsciously judge a potential partner’s health and genetic compatibility. The second is “pair bonding,” where kissing serves to maintain an emotional connection and commitment between partners in a long-term relationship.

The third proposed function is the “arousal hypothesis.” This theory suggests that the primary biological purpose of kissing is to initiate sexual arousal and prepare the body for intercourse. While this seems intuitive, previous scientific attempts to prove this hypothesis have failed to find a strong link. Past data did not show that kissing consistently acts as a catalyst for sexual arousal.

The researchers behind the current study argued that these previous attempts were looking at the problem too narrowly. Earlier work focused almost exclusively on the physical sensation of kissing, such as the sensitivity of the lips or the exchange of saliva. This approach largely ignored the mental and emotional state of the person doing the kissing. The researchers hypothesized that the physical act of kissing might not be arousing on its own without a specific cognitive component. They proposed that sexual fantasy serves as this missing link.

“People have tested three separate hypotheses to explain why we engage in romantic kissing as a species,” said study author Christopher D. Watkins, a senior lecturer in psychology at Abertay University. “At the time there had been no evidence supporting the arousal hypothesis for kissing – that kissing may act as an important catalyst for sex. This may be because these studies focussed on the sensation of kissing as the catalyst, when psychological explanations are also important (e.g., the mental motives for kissing which in turn makes intimacy feel pleasurable/desirable).”

To test this idea, the researchers designed an online study to measure the relationship between fantasy proneness and kissing preferences. They recruited a sample of 412 adults, primarily from the United Kingdom and Italy. After removing participants who did not complete all sections or meet the age requirements, the final analysis focused on 212 individuals. This group was diverse in terms of relationship status, with about half of the participants reporting that they were in a long-term relationship.

Participants completed a series of standardized questionnaires. The first was the “Good Kiss Questionnaire,” which asks individuals to rate the importance of various factors when deciding if someone is a good kisser. These factors included sensory details like the taste of the partner’s lips, the pleasantness of their breath, and the “wetness” of the kiss. The questionnaire also included items related to “contact and arousal,” asking how important physical touching and the feeling of sexual excitement were to the experience.

The scientists also administered the “Sexual Fantasy Questionnaire.” They specifically focused on the “intimacy” subscale, which measures how often a person engages in daytime fantasies about romantic interactions with a partner. This measure was distinct from fantasies that occur during sexual acts or while dreaming. It focused on the mental habit of imagining intimacy during everyday life.

To ensure their results were precise, the researchers included control measures. They measured “general creative experiences” to assess whether a person was simply imaginative in general. This allowed the scientists to determine if the results were driven specifically by sexual fantasy rather than just a vivid imagination. They also measured general sexual desire to see if the effects were independent of a person’s overall sex drive.

The results supported the researchers’ primary prediction. The analysis showed a positive correlation between daytime intimate fantasy and the importance placed on arousal and contact in a good kiss. Individuals who reported a higher tendency to fantasize about intimacy were much more likely to define a “good kiss” as one that includes high levels of physical contact and sexual arousal.

“Your tendency to think and fantasise about intimacy during the day is related to the qualities you associate with a good-quality kiss,” Watkins told PsyPost. “Specifically, the importance we attach to contact and arousal while kissing. As such, our mental preoccupations could facilitate arousal when in close contact with an intimate partner – explaining personal differences in how we approach partners during intimate encounters.”

This relationship held true even after the researchers statistically controlled for other variables. The link between fantasy and kissing preferences remained significant regardless of the participant’s general creativity levels. This suggests that the connection is specific to sexual and romantic cognition, not just a byproduct of having a creative mind.

Additionally, the finding was independent of general sexual desire. While people with higher sex drives did generally value arousal more, the specific habit of fantasizing contributed to this preference over and above general desire. This implies that the mental act of simulating intimacy creates a specific psychological context. This context appears to shape what a person expects and desires from the physical act of kissing.

The study also yielded secondary findings regarding kissing styles. The researchers looked at “reproductive potential,” which they measured by asking participants about their history of sexual partners relative to their peers. This is often used in evolutionary psychology as a proxy for mating strategy. The data showed that individuals with a history of more sexual partners placed greater importance on “technique” in a good kiss. Specifically, they valued synchronization, or whether the partner’s kissing style matched their own.

“One unplanned relationship found in the data was between the importance people placed on technique (e.g., synchronicity) in a good kiss and the extent to which people reported tending to have sex with different people across their relationship history (compared to average peer behavior),” Watkins said. “This may suggest that people who seek sexual variety also seek some form of similarity in partners while intimate (kissing style). This was a small effect though that we would like others to examine/replicate independently in their own studies.”

As with all research, there are some limitations. The research used a cross-sectional design, meaning it captured data from participants at a single point in time. As a result, the researchers cannot prove that fantasizing causes a change in kissing preferences. It is largely possible that the relationship works in the reverse direction, or that a third factor influences both.

The sample was also heavily skewed toward Western cultures, specifically the UK and Italy. Romantic kissing is not a universal human behavior and is observed in less than half of known cultures. Consequently, these findings may not apply to cultures where kissing is not a standard part of romantic or sexual rituals.

Future research could address these issues by using longitudinal designs. Scientists could follow couples over time to see how the relationship between fantasy and physical intimacy evolves. This would help clarify whether increasing intimate fantasy can lead to a more revitalized physical connection.

“We are looking to develop our testing instruments to explore other experiences related to kissing, and expand our studies on this topic – for example, by establishing clear cause and effect between our thoughts/fantasies and later kissing behaviors or other behaviors reported during close contact with romantic partners,” Watkins said.

The study, “Proclivity for sexual fantasy accounts for differences in the perceived components of a ‘good kiss’,” was authored by Milena V. Rota and Christopher D. Watkins.