How Does the Coolidge Effect Influence Human Relationships?

The Coolidge effect is connected with the attraction felt toward novelty when it comes to sex. However, how is this phenomenon related to monogamy, couple relationships, or infidelity?
How Does the Coolidge Effect Influence Human Relationships?

Last update: 12 April, 2022

The Coolidge effect concerns the fact that we feel more attracted when a new sexual partner appears on the scene. Its existence has been demonstrated both in humans and in other mammals, although there are certain nuances.

The biological explanation suggests that, given the possibility of a new sexual relationship with a new or different partner, our dopamine levels increase. This increase makes our excitement greater.

Is this effect purely biological? How is it related to infidelities, open relationships, or attraction to porn? When you fall in love, can the Coolidge effect also interfere with your relationship? Or is there less risk? Let’s find out.

Man looking at a woman on the street

The Coolidge effect

The Coolidge effect is a phenomenon observed in both men and women (and male and female animals) in which an increased willingness to have sex in the presence of new receptive partners is demonstrated (Brown, 1974).

In other words, it alludes to the tendency to notice and feel attracted to novelty in the sexual field. It’s related to an increase in dopamine levels. This effect has been demonstrated in mammals and the term was coined in 1955 by the ethologist, Frank A. Beach. However, as stated in Dewsbury (2000), it was a psychology student who suggested this term to him.

The story behind it

Behind the Coolidge effect lies a curious event that explains its origin. Mentioned in Dewsbury (2000), it took place in the 1920s, when the US president at the time, Calvin Coolidge, was visiting a farm with his wife Grace.

Grace noticed that there was a rooster that mated frequently, prompting her to ask the farmer, “How many times a day does this rooster usually have intercourse?” The farmer replied, “Dozens.”

Then Coolidge’s wife, fascinated by his answer, asked the farmer to tell her husband. He did, and the president replied: “Always with the same hen?”, to which the farmer replied: “No, no, with different hens”. “Then tell that to Mrs. Coolidge”, concluded the president. From this anecdote, which many understood to be a joke, arose the effect that bears the name of the president, the Coolidge effect.

How does it influence relationships?

How does the Coolidge effect influence relationships? Some authors claim that this phenomenon is behind aspects such as infidelity, porn, or the fact that there are more and more couples who decide to embark on open relationships, thus fleeing from traditional monogamy.

The reality is that novelty attracts us. We like it and it excites us which explains the Coolidge effect. Nevertheless, not everyone will end up being unfaithful, much in the same way that we don’t all like movies with erotic content. However, the Coolidge effect could go a certain way to explaining the appearance of this kind of behavior when it occurs.

For example, with porn, large numbers of videos with extremely different protagonists can be accessed, which keeps dopamine levels high.

What about falling in love?

The Coolidge effect could make certain evolutionary sense in animals that seek to perpetuate their species with as many offspring and genetic richness as possible. On the contrary, in the case of humans, it’s not so easy to extrapolate. For instance, when you fall in love, you don’t really care about the novelty aspect, you only want to be with your loved one.

Nonetheless, this can all be related to dopamine. That’s because, when you fall in love, its levels (as well as that of other hormones) increase exponentially. Furthermore, when something greatly surprises you, such as when you’re faced with novel experiences, your dopamine levels are also high.

However, according to experts, when you enter a routine phase in your relationship, your dopamine levels begin to decline. This means that, rather than being euphoric as you were at the beginning of your relationship, you’re a lot calmer. Thus, it’s at these moments that the Coolidge effect may appear.

Bored woman hugging her boyfriend

The Coolidge effect and sex

As we mentioned earlier, the Coolidge effect has been demonstrated in mammals (rodents), but also in humans. An example of this happens after sex. Indeed, in men, after ejaculating, the so-called refractory period appears. This is the time necessary for them to become aroused again. Depending on certain factors, it usually lasts a few minutes.

Nevertheless, this period decreases when the man is with a new partner. This would partly explain the Coolidge effect. Therefore, keeping a relationship alive by way of changes in sexual routine, new positions, sex toys, etc can help in this respect.

As you can see, the Coolidge effect, although it’s been tested in humans, doesn’t have to happen to everyone in the same way. Undoubtedly novelty is attractive, especially at the ‘biological’ level, but there are nuances.

On the other hand, there are biological roots to this phenomenon. Furthermore, it mustn’t be forgotten that, as well as being animals, we’re also people, so the most rational and human aspects, as well as those related to feelings, also have their role here. Consequently, these particular elements or facets of the individual could modulate the Coolidge effect.

“There’s a huge difference in sex and making love. We have sex with someone who can satisfy us physically, but we make love to someone who can satisfy us soulfully and eternally.”

-Mehek Bassi-

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  • Brown, R. E. (1974). Sexual arousal, the Coolidge effect and dominance in the rat (Rattus norvegicus). Animal Behaviour (en inglés) 22(3): 634-637.
  • Dewsbury, Donald A. (2000) Frank A. Beach, Master Teacher, Portraits of Pioneers in Psychology, 4: 69-281
  • Reber, E.; Reber. (2001). The Penguin dictionary of psychology (en inglés) (3.ª edición). Londres: Penguin.