Effects of a Single-Session Implicit Theories of Personality Intervention on Recovery From Social Stress and Long-Term Psychopathology in Early Adolescents

Abstract

Efforts to reduce youth mental health problems have advanced greatly in recent years, but they have not lowered rates of youth mental illness on a large scale. Thus, a need exists for disseminable, mechanism-targeted approaches to reducing youth psychopathology. The present study tested whether a single-session, self-administered intervention teaching an incremental theory of personality (i.e., the belief that one’s personality is malleable), compared to a comparison intervention, could impact psychopathology risk factors and reduce internalizing psychopathology over 9 months in high-symptom early adolescents. The intervention’s effects on two established risk factors for youth internalizing problems—impaired social stress recovery and low perceived control—were explored, with improvements in these domains examined as mechanisms of intervention effects. Youths were randomized to receive a brief, computer-based implicit theories intervention or a supportive-therapy control. At post-intervention, youths underwent a lab-based social stressor to assess intervention effects on physiological stress recovery; at baseline and 3-, 6-, and 9-month follow-ups, youths reported their levels of perceived primary (i.e., behavioral) control and secondary (i.e., emotional) control, and parents and youths reported youth anxiety and depressive symptoms. Youths in the intervention group experienced significantly greater improvements than did control group youths in parent-reported depression (d = 0.60), youth-reported depression (d = .32), parent-reported anxiety (d = .28), and perceived primary control (d = .29) from baseline to 9-month follow-up. Intervention effects were non-significant for youth-reported anxiety and perceived secondary control, although effect sizes at 9-month follow-up were in the small-to-medium range (ds = .33 and .24). Youths in the intervention group also experienced more rapid reductions in parent- and youth-reported depression across the follow-up period, compared to control group youths. Stronger baseline entity theories predicted smaller youth-reported symptom declines across the follow-up period; independent of this effect, larger pre- to post-intervention reductions in entity theories predicted greater symptom reductions across the follow-up period. Regarding mechanisms of intervention effects, 3-month improvements in perceived primary (but not secondary) control mediated greater reductions in youth-reported anxiety and depression at 9-month follow-up. Changes in perceived control did not mediate intervention effects on parent-reported youth internalizing symptoms. Finally, youths who received the intervention recovered more than three times as rapidly from a lab-based social stress task than did youths who received the comparison program, based on both sympathetic (EDA) and parasympathetic (rMSSD) post-stressor recovery slopes. However, post-intervention stress recovery rates did not account for changes in youth internalizing distress at 9-month follow-up. Findings suggest a scalable, cost-effective strategy for reducing youth internalizing distress in high-symptom early adolescents.