Scientists discover a pet’s fascinating “afterglow effect” on romantic couples

A recent study published in the Journal of Social and Personal Relationships provides new evidence that having a pet present during interactions with romantic partners or friends may increase visible signs of positive emotion, such as smiling and laughing. These effects were especially noticeable for romantic partners and could even persist after the pet was no longer in the room.

Previous studies had produced mixed findings about the benefits of pet ownership, with some pointing to improved mood and life satisfaction, and others finding no effects or even negative ones. One reason for the inconsistent results may be that most studies focus only on pet ownership rather than the specific contexts in which pets are involved.

For instance, it may not be pet ownership itself that affects well-being, but how often people interact with their pets during social situations. Additionally, much of the prior research has relied on self-report surveys rather than direct behavioral observation, and most of it has been conducted with unfamiliar animals or in therapeutic contexts rather than everyday settings with people’s own pets.

“There has been a lot of research on the links between pet ownership and mental and physical health, and I believe it is now time to investigate the nuances of pet ownership in more detail and how it can impact different areas of humans’ lives, which could also explain the mechanisms underlying its positive links to well-being,” explained study author Ece Beren Barklam, who recently completed her PhD in psychology at Kingston University London.

“This is the first experimental study to explore this particular topic, and the findings encourage further research to establish how exactly pets affect romantic relationships and friendships, particularly when there are varying levels of closeness and satisfaction in both the human-human relationships and human-pet relationships.”

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For their study, the researchers recruited 164 participants, formed of 37 romantic couple dyads and 45 friend dyads. All dyads had known each other for at least three months. Some participants were pet owners and others were not. Among the pet owners, half were randomly assigned to bring their pet dog or cat to the observation session, while the other half were assigned to a control condition with a large stuffed dog toy.

Non-pet owners also interacted with the stuffed toy. This design allowed the researchers to compare the effects of actual pets versus a lifelike but inanimate object. The pets included a mix of cats and dogs, varying in breed and size.

Each pair participated in three five-minute sessions in a room equipped with discreet cameras. In the first session, they interacted freely without any animal or toy. In the second, they interacted with either their pet or the stuffed toy. In the third session, the pet or toy was removed, and the pair interacted again.

The researchers used a standardized tool called OHAIRE-v3 to code video footage, focusing on positive facial expressions, such as smiling or laughing, as indicators of positive emotion. They also recorded and analyzed both observed and self-reported human-animal interactions, and they assessed participants’ mood using a validated questionnaire before and after each session.

The main finding was that pet presence was associated with more positive facial expressions than the presence of a stuffed animal. This effect was most noticeable in the second session, when the pet was present, but in romantic couples, the elevated emotional display continued into the third session even after the pet had been removed. This pattern was not found in friend dyads, suggesting that pets may have a longer-lasting influence on interactions between romantic partners compared to friends.

In the romantic couples, those who interacted with a pet in the room showed higher levels of smiling and laughing than non-pet owners who interacted with the stuffed toy. Pet owners who were assigned to the toy condition also showed somewhat higher levels of positive expression than non-pet owners, even though no real pet was present. The researchers speculate that this might reflect a “cognitive presence” of the pet, where pet owners think or talk about their animals during the interaction, possibly triggering similar emotional responses.

In friend dyads, pet presence had a more immediate effect, increasing positive expressions during the session when the pet was in the room. However, once the pet was removed, emotional display returned to earlier levels. This suggests that pets may act as social facilitators or emotional amplifiers in friendships, but the effect may be limited to the time when the pet is physically present.

The researchers also looked at changes in self-reported mood. Overall, mood improved from the start of the study to the first session, possibly due to the enjoyable nature of the interaction itself. In friend dyads, mood increased further after interacting with a pet, while those who interacted with a toy did not report any additional mood improvements. Among romantic couples, mood patterns were less consistent, but those who interacted with a pet tended to maintain their mood gains, while those in the toy condition did not.

One unexpected finding was that the participants’ observed behaviors with the pet, such as petting or feeding, were not linked to how positive they appeared or how good they reported feeling. However, participants’ own ratings of their interactions with the pet—how much they felt the pet was engaged with them—were associated with more smiling and laughing. This suggests that subjective perception of the interaction may be more relevant to emotional outcomes than objective measures of behavior.

The researchers also explored several secondary questions. They found that well-being, measured using a standard index, was not directly associated with pet ownership, pet attachment, or attitudes toward pets. However, among non-pet owners, those who had more positive attitudes toward pets tended to report higher romantic relationship satisfaction.

Among pet owners, those who saw their pet as a substitute for people also reported higher satisfaction with their romantic relationship. These findings raise the possibility that personal traits related to how individuals relate to animals might be linked to how they experience their human relationships.

“The results illustrate that pets can have a positive effect on humans’ facial expressions (e.g., smiling and laughing) and mood during social interactions with other humans, potentially even if the pet is not physically present, as pets can have a cognitive presence in humans’ minds in the form of thoughts and feelings,” Barklam told PsyPost. “This effect on social interactions could indirectly have a positive effect on humans’ overall well-being.”

“Interestingly, the effects seemed to be different for friends and romantic couples, where there might be a longer-lasting effect for those in more intimate relationships. It is also important to note that people who choose to have pets might have a variety of different personal characteristics from people who choose to not have pets, which might play an important role and requires further investigation.”

“For example, the results showed that while pet ownership itself was not directly linked to relationship satisfaction, more positive attitudes toward pets in non-pet owners were linked to higher romantic relationship satisfaction,” Barklam explained. “Overall, the findings can encourage people to spend more time together in the presence of their pets, and romantic couples could consider having a companion animal together to potentially enhance their relationships, if they have the desire and ability to care for a pet.”

The study, like all research, has some caveats. Participants were aware that they were being recorded, which might have influenced their behavior. In addition, the sample was mostly composed of people who had high levels of satisfaction with their friendships or relationships, limiting the ability to explore whether pets might help improve strained relationships.

Despite these limitations, the new findings suggest that pets may play a subtle but meaningful role in shaping human social experiences. Whether through physical presence or through memories and emotional associations, companion animals may help people feel closer to one another.

The study, “The effects of pets and human-pet interactions on humans’ romantic relationships and friendships,” was authored by Ece Beren Barklam and Fatima Maria Felisberti.