ACT yearnings and SDT basic psychological needs: a conceptual comparison and integrative perspective

This paper examines the conceptual relationship between the notion of yearnings in Acceptance and Commitment Therapy (ACT) and basic psychological needs in Self-Determination Theory (SDT). While recent literature has placed these constructs in dialogue, their structural relationship remains theoretically under-specified. Drawing on SDT’s formal criteria for defining basic psychological needs, the present analysis offers a systematic comparison between ACT yearnings and SDT needs at both structural and content levels. Although the two frameworks differ in theoretical architecture, meaningful convergence emerges at motivational and partially conceptual levels. Alignment emerged between belonging and relatedness, and between competence constructs, whereas the relationship between meaning and autonomy appears partial. Other yearnings, including orientation, coherence, and feeling, do not demonstrate direct conceptual equivalence but may relate indirectly to need satisfaction through mindfulness-related flexibility processes. From an integrative perspective, psychological flexibility is proposed as a potential regulatory pathway through which engagement with core motivational criteria translates into adaptive functioning.