Self-expansion perceptions and behaviors uniquely contribute to relationship quality over time.

Self-expansion refers to the process of broadening the self via engaging in novel activities, gaining new skills, and acquiring new perspectives and is proposed to be driven in large part by one's close relationships. Self-expansion experiences include perceptions of potential (i.e., beliefs about how self-expanding a relationship could be in the future), perceptions of current experiences (i.e., beliefs about how self-expanding a relationship is present), and enacted behaviors (i.e., engagement in novel, interesting activities). In two preregistered dyadic daily experience studies, we examined whether self-expansion potential is an antecedent to behavioral self-expansion and current perceptions, and how these distinct self-expansion components uniquely and synergistically predict relationship satisfaction and commitment daily and over time. Results revealed that self-expansion potential prospectively predicted both behavioral self-expansion and daily perceptions of current self-expansion. Self-expansion potential, current perceptions, and behaviors separately predicted greater relationship satisfaction and commitment daily. Self-expansion potential-but not behaviors or current perceptions-also positively predicted satisfaction and commitment 2 months later. Implications regarding the power of potential in relationships are discussed, including the need for future research to consider this important facet of self-expansion. (PsycInfo Database Record (c) 2024 APA, all rights reserved).