Effects of preference alignment and client-rated attachment style on therapy: The moderating role of interpersonal synchrony.

Objective: This study aims to explore whether activity-preference alignment provides unique contributions to the working alliance and counseling outcomes beyond the client-rated adult attachment style, and to examine the moderating roles of behavioral and brain synchrony in this process.

Methods: Sixteen pairs of counselors and clients participated in five consecutive weekly counseling sessions. The 1st, 3rd, and 5th sessions took place offline in a near-infrared laboratory, while the 2nd and 4th sessions were conducted online via video conferencing.

Results: After controlling for the client-rated adult attachment style, preference alignment showed a significant impact on symptom improvement. Specifically, preference alignment had a significant positive predictive effect on symptom improvement when counselor-guided behavioral synchronization was high. Attachment avoidance also negatively predicted the working alliance but only when client-guided brain synchronization in the temporoparietal junction was low.

Conclusion: The study suggests that preference alignment provides unique insights into symptom improvement beyond client-rated attachment style alone. Counselor-guided behavioral synchrony amplifies the effect of preference differences on symptom improvement, whereas client-guided brain synchrony reduces attachment avoidance's impact on the working alliance. These findings highlight that behavioral and brain synchrony impact therapeutic outcomes differently based on who guides the process, emphasizing the need to consider both interpersonal dynamics and alignment factors in counseling.