Changes in cognitive and behavioral control after lamotrigine and intensive dialectical behavioral therapy for severe, multi-impulsive bulimia nervosa: an fMRI case study

Purpose: Adults with bulimia nervosa (BN) and co-occurring emotional dysregulation and multiple impulsive behaviors are less responsive to existing interventions. Initial data suggest that the combination of Dialectical Behavior Therapy (DBT) and a mood stabilizer, lamotrigine, significantly reduces symptoms of affective and behavioral dysregulation in these patients. Identifying candidate neurobiological mechanisms of change for this novel treatment combination may help guide future randomized controlled trials and inform new and targeted treatment development. Here, we examined neurocognitive and symptom changes in a female patient with BN and severe affective and behavioral dysregulation who received DBT and lamotrigine. Methods: Go/no-go task performance data and resting-state functional MRI scans were acquired before the initiation of lamotrigine (after 6 weeks in an intensive DBT program), and again after reaching and maintaining a stable dose of lamotrigine. The patient completed a battery of symptom measures biweekly for 18 weeks over the course of treatment. Results: After lamotrigine initiation, the patient made fewer errors on a response inhibition task and showed increased and new connectivity within frontoparietal and frontolimbic networks involved in behavioral and affective control. Accompanying this symptom improvement, the patient reported marked reductions in bulimic symptoms, behavioral dysregulation, and reactivity to negative affect, along with increases in DBT skills use. Conclusion: Improved response inhibition and cognitive control network connectivity should be further investigated as neurocognitive mechanisms of change with combined DBT and lamotrigine for eating disorders. Longitudinal, controlled trials integrating neuroimaging and symptom measures are needed to fully evaluate the effects of this treatment. Level of Evidence: IV: Evidence obtained from multiple time series with or without the intervention, such as case studies.