The Self-Determination of Sexual Desire: An Exploration of the Relationship Between Self-Determined and Non-Self-Determined Sexual Motivation, Sexual Need Satisfaction and Frustration, and Sexual Desire

Abstract

Sexual desire, one’s interest in sexual activity, is a robust correlate of sexual and relationship satisfaction. However, for many, sexual desire decreases over time, and low desire is associated with lower sexual and relationship satisfaction and higher psychological distress and is the primary reason people seek couples and sex therapy. Given its beneficial role, understanding the conditions that may maintain or promote sexual desire would confer overall sexual and psychological benefits. Self-determination theory proposes a motivational framework in which fulfillment of the basic psychological needs for autonomy, competence, and relatedness leads to greater well-being and optimal function. Drawing from two independent samples, I examined the associations between basic psychological need satisfaction and frustration during sexual experiences and markers of sexual function and well-being, including sexual desire, and assessed sexual motivation as the mechanism through which one’s basic psychological need satisfaction and frustration during sexual experiences contributes to reported sexual desire. In Study 1, I adapted and validated the Basic Psychological Need Satisfaction and Frustration Scale to sexual experiences among sexually active individuals and examined hypothesized links between basic psychological need satisfaction and frustration during sexual experiences and sexual outcomes. The adapted measure (BPNSFS-Sex) demonstrated good model fit and adequate criterion and construct validity. Further, additional analyses revealed that the constructs related to self-determination theory explained more of the variance in sexual and relationship outcomes than other motivational frameworks (approach-avoidance and communal motivation models). Considered together, I discuss how the results highlight the basic psychological needs of autonomy, competence, and relatedness as important factors within sexual experiences that, when satisfied, are associated with greater self-determined motivation, sexual desire, sexual satisfaction, and sexual function and when frustrated are associated with greater non-self-determined motivation and sexual distress, and lower sexual function. In Study 2, I examined a mechanism for the association between basic psychological need satisfaction and frustration during sexual experiences and sexual desire by testing sexual motivation as a mediator. Specifically, I used a longitudinal (cross-lagged) parallel mediation model to determine whether self-determined and non-self-determined sexual motivation mediate the relationships between basic psychological need satisfaction and frustration during sexual experiences and sexual desire, controlling for gender and relationship length. Interestingly, results demonstrated a significant negative indirect effect of basic psychological need frustration during sexual experiences on sexual desire through self-determined sexual motivation, demonstrating full mediation. In other words, self-determined sexual motivation was found to mediate the relationship between basic psychological need frustration during sexual experiences and sexual desire. These findings are unexpected in that basic psychological need frustration during sexual experiences—rather than basic psychological need satisfaction during sexual experiences—shows a stronger (though negative) association with self-determined sexual motivation and subsequent sexual desire. Thus, highlighting the importance of minimizing basic psychological need frustration during sexual experiences, in order to foster greater sexual desire. Across these two studies, I aimed to extend our understanding of the contributions of basic psychological need satisfaction and frustration during sexual experiences to self-determined and non-self-determined sexual motivation and sexual desire. In the General Discussion, I present the theoretical and practical implications of conceptualizing desire as a motivational and emotional state that can be cultivated or diminished through basic psychological need satisfaction or frustration during sexual experiences, respectively, and how self-determined sexual motivation drives this association. The objective of this dissertation was to extend our understanding of the contributions of basic psychological need satisfaction and frustration during sexual experiences to self-determined and non-self-determined sexual motivation and sexual desire.