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The One Step Couples Can Take to Increase Their Sex Drive

Working on the trait that helps them connect while remaining distinct.

Key points

  • Self-expansion theory suggests that one way we try to grow and expand our sense of self is through romantic relationships.
  • Two concepts related to self-expansion are closeness (taking on aspects of one’s partner) and otherness (seeing one’s partner in a new light).
  • New research shows self-expansion is associated with higher levels of closeness and otherness, resulting in increased sexual desire.
Source: dindolyna89/Pixabay

People’s sexual desire for their partners is not constant. In fact, for various reasons (e.g., fading novelty), sexual desire tends to decline over time. However, this is not true for all couples. Why?

According to recent research by Goss et al., published in the August issue of the Journal of Social and Personal Relationships, the answer may have something to do with self-expansion.

The study investigated the predictions of self-expansion theory—specifically, that “people are innately driven to grow, and that romantic relationships are a primary way that people expand their sense of self.” Self-expansion, this research concluded, is associated with “higher closeness and otherness, and, in turn, higher sexual desire.”

Before we continue, some definitions:

  • Closeness: Feeling connected to your romantic partner and taking on their aspects as your own.
  • Otherness: Feeling that you are learning new or unique things about your romantic partner.
  • Self-expansion: Shared (new) experiences with your romantic partner that expand your worldview and sense of self.

Investigating Self-expansion and Increased Sexual Desire

Study 1

Sample: 242 sexually active individuals (48 percent men); mean age of 33 years old; average relationship length of nine years; 66 percent white; 81 percent heterosexual and 9 percent bisexual; 47 percent married; 69 percent with children.

Methods and Measures

Participants completed daily surveys for 21 days. The following were measured:

  • Self-expansion. Six items from the Self-Expansion Questionnaire (SEQ). Example: “How much has knowing your partner made you a better person?”
  • Closeness. A single item from the Need Satisfaction Scale: “Today, when I was with my partner, I felt a lot of closeness and intimacy.”
  • Otherness. Two items: “Today, I learned something about my partner that I didn’t know,” and “Today, I saw a new side of my partner.”
  • Sexual desire. “Today, I felt great sexual desire for my partner.”
  • Relationship satisfaction. One item from the Perceived Relationship Quality Components Inventory: “How satisfied are you with your relationship?”

Study 2

Sample: 368 individuals (48 percent men); mean age of 32 years old; average relationship length of eight years; 70 percent white; 81 percent heterosexual and 19 percent bisexual; 41 percent married; 22 percent with children.

Methods and Measures

The investigation included a 45-minute background survey followed by three weekly surveys.

Measures comprised the following:

  • Self-expansion. Three items from the SEQ.
  • Closeness. The Inclusion of Other in Self (IOS) Scale. Participants were instructed to indicate their couple identity by choosing from seven pairs of progressively overlapping circles representing the person and their romantic partner.
  • Otherness. Three questions, similar to Study 1.
  • Sexual desire. Same as in the previous investigation.
  • Relationship satisfaction. “I felt satisfied with my relationship.”

Study 3

Sample: 319 individuals (42 percent men); mean age of 37 years old; average relationship length of 12 years; 85 percent white; 86 percent heterosexual and 7 percent bisexual; 53 percent married; 45 percent with children.

Methods and Measures

Participants were randomly assigned to three groups: A familiar and comfortable group, a self-expansion group, and a control group.

The first two conditions required completing a recall task. Specifically, participants were instructed to recall a time when they had engaged in one of the following two types of activities with their partner:

  • A new and exciting activity (self-expansion condition)
  • A familiar and relaxing activity (familiar and comfortable condition)

They were asked to describe “how the experience made them feel when the experience occurred, and how difficult it was to recall.”

Subsequently, all completed a number of measures:

  • Closeness. As in the second study.
  • Otherness. Four items. Example: “I am still learning things about my partner that I didn’t know before.”
  • Sexual desire. “How much sexual desire or interest do you feel for your romantic partner right now?”
  • Relationship satisfaction. “How satisfied are you with your relationship right now?”
Source: VladBitte/Pixabay

“Closeness” and “Otherness” Increase Sexual Desire

The findings supported the link between self-expansion and sexual desire and suggested the link may be explained by closeness and otherness.

But closeness alone is insufficient for explaining the relationship between self-expansion and sexual desire because some people with high levels of intimacy and closeness still experience low sexual desire.

So, sexual desire also requires high levels of otherness—the psychological distance that allows one to see their partner in a new way and learn novel and interesting things about them.

Why do high relationship satisfaction and sexual desire require that enhanced closeness be accompanied by enhanced otherness?

Maybe because closeness alone results in the “fusion” of partners. And, as self-determination theory has suggested, people need not only to feel connected and intimate but to experience themselves as distinct, autonomous, and competent individuals.

That is why engaging in self-expanding activities is important. As Goss and coauthors note, engaging in self-expanding activities may present “opportunities for otherness by putting partners in novel, exciting, or challenging situations in which learning something new about [the person’s intimate partner] is more likely and may foster desire as they present opportunities for further self-expansion.”


According to theory, self-expansion is associated with higher sexual desire. However, self-expansion and sexual desire tend to decline over time.

Self-expansion is linked to desire because it “creates opportunities for partners to feel closer to each other and appreciate the unique and novel ways that each person contributes to the relationship,” thus “fostering desire.”

Indeed, individuals in a romantic relationship often function best when they feel connected but distinct and have both a sense of belonging and autonomy.

So, to keep the spark alive, both partners need to maintain self-expansion. How? Here are some suggestions:

  • Take classes together or use online resources to learn something new.
  • Visit a new place—museums, botanical gardens, vineyards, zoos, antique stores, etc.
  • Try a new activity—making pizza, fruit picking, dancing, hiking, and kayaking.
  • Share opinions about a topic you rarely discuss—anything from favorite childhood TV shows to plans for retirement.

Facebook image: Cherries/Shutterstock

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