Brain Changes After a Parenting Intervention in Adolescent Girls With Internalizing Symptoms

Importance: Parenting interventions can improve adolescent internalizing outcomes, but their impact on neurobiological mechanisms remains unclear. Understanding neurobiological mechanisms underpinning the effects of parenting interventions is crucial for treatment refinement and development. Objective: To investigate the effects of an emotion-focused parenting intervention on adolescent brain function and to determine whether intervention-induced brain changes are associated with behavioral and clinical outcomes. Design, Setting, and Participants: This randomized clinical trial was conducted from April 2022 to June 2024. Participants were mother-daughter dyads, with daughters aged 10 to 12 years who scored above the 50th percentile on the Revised Children's Anxiety and Depression Scale. Adolescents completed functional magnetic resonance imaging (MRI) at baseline and 6-month follow-up. Intervention: Manualized Tuning In to Teens (TINT) intervention was delivered 1:1 to mothers in 8 weekly sessions. Main Outcomes and Measures: Change in neural activation in the prefrontal cortex and amygdala during emotion regulation from baseline to 6-month follow-up, measured using functional MRI. In addition, associations between neurofunctional changes and improvements in maternal emotion socialization and adolescent internalizing symptoms were evaluated. Results: Of the 70 female adolescents and their mothers included, 35 were randomized to parenting intervention (mean [SD] adolescent age, 11.4 [0.7] years), and 35 were randomized to a waitlist control group (mean [SD] adolescent age, 11.5 [0.8] years). Adolescents whose mothers received the intervention exhibited increased activation in the superior frontal gyrus (SFG) during implicit emotion regulation (B = 1.75; 95% CI, 0.95-2.54; family-wise error [FWE] P = .002) and decreased activation in the inferior frontal gyrus (IFG) during explicit emotion regulation (B = -1.63; 95% CI, -2.43 to -0.84; FWE P = .03) compared with controls. Changes in SFG and IFG activation were associated with reductions in unsupportive maternal emotion socialization of sadness (Pearson r = -0.50; false discovery rate [FDR] P <.001) and anxiety (Pearson r = -0.38; FDR P = .009), and reductions in adolescent anxiety (Pearson r = 0.34; FDR P = .02) and internalizing symptoms (Pearson r = 0.32; FDR P = .03), respectively. Conclusions and Relevance: The findings of this randomized clinical trial revealed that an emotion-focused parenting intervention can impact prefrontal cortex functioning during emotion regulation in early adolescent girls with internalizing difficulties. Trial Registration: ANZCTR.org.au: ACTRN12621001304820P.