Paul E. Croarkin, D.O., is focused on understanding the neurobiology, optimal treatment and classification of mood disorders in children and adolescents. This includes studies of repetitive transcranial magnetic stimulation (rTMS) for adolescent major depressive disorder; collaborative clinical trials; studies of neurophysiology with magnetic resonance spectroscopy (MRS); and novel, single and paired-pulse transcranial magnetic stimulation (TMS) paradigms.

A central theme among Dr. Croarkin's research is investigating the role of gamma-aminobutyric acid (GABA) and glutamate neurotransmitter systems in early-onset mood disorders with the goal of informing safer and more effective biologic treatments.

Focus areas

• Longitudinal TMS and MRS study of GABAergic and glutamatergic neurotransmission in adolescents with major depressive disorder in treatment with selective serotonin reuptake inhibitors (SSRIs)
• Double-blind, randomized controlled trial of high-frequency rTMS in adolescents with major depressive disorder to examine the effectiveness of this novel treatment and putative mechanisms of action
• Collaborative, longitudinal, cohort study of youth in treatment with SSRIs or psychotherapy to assess the safety and effectiveness of these two interventions
• Mayo Clinic bipolar biobank genomic studies in youth to examine risk factors and optimum treatments for youth bipolar disorder

Significance to patient care

Mood disorders, such as major depressive disorder, are significant and common problems in children and adolescents. Adolescent depression frequently involves a biological component and ensuing delayed recovery, frequent recurrences, comorbidity, substance abuse, and increased risk of suicide.

Initial management of moderate to severe major depressive disorder in adolescents involves treatment with psychotherapy and SSRIs. Remission rates and outcomes are often poor as this treatment does not target relevant, underlying adolescent pathophysiology. Ongoing controversy regarding the effectiveness and safety of SSRIs in young individuals underscores the importance for an improved understanding of the biological mechanisms involved in adolescent depression.

Dr. Croarkin and his research team are focused on understanding the pathophysiology of mood disorders and developing more effective treatments that will enhance individual outcomes and impact a considerable societal burden.