Unravelling the “equivalence paradox”: An exploration of possible mechanistic explanations for the equivalence of the person-centred approach and cognitive behavioural therapy

Abstract

This project adopted a neuroscience perspective to explore the reason for the Equivalence Paradox, that is the finding that quite different therapeutic modalities are, as an approximation, equally effective. The project focussed on the equivalence of cognitive behavioural therapy (CBT) and person-centred therapy (PCT). This project is believed to be the first time that a practitioner group with a balance of allegiances has drawn conclusions from the intersection of neuroscience and psychotherapy. A literature search uncovered a set of findings or views (neuroscience elements) with possible relevance to the problem. In a focus group (or workshop) format, a group of PCT and CBT therapists contributed their understanding of healing processes based on their practice experience. They were then asked to match these experiences to the set of neuroscience elements provided. The group found that there are important similarities in terms of the therapeutic relationship and the desired endpoint, namely a more integrated, more congruent brain; however there were also significant differences in terms of processes that correlate to what is actually “done” in therapy. In CBT, affect-modulating left cortex and executive processes lead, whereas in PCT there is an emphasis on left-right and cortical-limbic “dialogue” and integration. Overall, together with literature observations, the project concluded that for CBT and PCT different healing routes can are progressed, most likely with the client filling in between sessions the healing steps that are not specifically catalysed by the therapy. However “equivalence” may be just about symptom reduction; a CBT-healed brain may differ from a PCT-healed brain.