838. Functional Neurological Symptoms in Bipolar Disorder: A Case Illustrating Affective Dysregulation and the Neuropsychiatric Interface Between Mood Instability and Conversion Symptom

Abstract

Abstract Background Functional Neurological Symptom Disorder (FNSD), previously known as conversion disorder, is increasingly understood within a neurobiological framework involving altered emotional processing, stress regulation, and dysfunctional brain network integration. Bipolar disorder is similarly associated with affective instability, circadian disruption, and impaired emotional regulation circuits. The coexistence of bipolar disorder and functional neurological symptoms remains underrecognized, despite shared mechanisms involving limbic–motor network dysregulation and stress-related neurobiological pathways. Understanding this interaction is important for optimizing neuropsychopharmacological and psychotherapeutic management. Aims & Objectives This case aims to demonstrate the clinical and neurobiological interaction between bipolar affective disorder and functional neurological symptoms and to highlight the role of mood stabilization in reducing somatic neurological manifestations. Objectives To describe functional neurological symptoms occurring in the context of bipolar affective disorder. To explore affective and psychosocial stressors contributing to symptom expression. To evaluate the impact of integrated psychopharmacological treatment on symptom improvement. Method This report describes a longitudinal clinical case evaluated in a psychiatric outpatient setting. Data were obtained through psychiatric interviews, mental status examinations, and clinical follow-up assessments. Diagnostic formulation followed standard psychiatric diagnostic criteria. Treatment consisted of supportive psychotherapy, psychoeducation, and pharmacological mood stabilization with follow-up monitoring of symptom progression. Results A 21-year-old female university student presented with involuntary movements involving the eyes, mouth, and tongue accompanied by finger twitching. Symptoms were variable, non-rhythmic, and partially controllable, inconsistent with organic neurological disorders. Psychological stress related to academic dissatisfaction and perceived lack of family support preceded symptom onset. Mental status examination revealed restlessness, rapid speech, labile affect, and preoccupation with somatic complaints. The patient was diagnosed with bipolar affective disorder, current episode mixed, comorbid with Functional Neurological Symptom Disorder. Treatment with divalproex extended-release and olanzapine, combined with supportive psychotherapy and psychoeducation, resulted in reduction of involuntary movements and improved behavioral control. Subsequent mood changes toward depressive symptoms prompted dose adjustment, after which clinical stabilization improved. Discussion & Conclusions This case highlights the interaction between affective dysregulation and functional neurological symptoms, supporting models of disrupted limbic–motor network connectivity and stress-mediated neural processing. Emotional conflict and reduced perceived autonomy may contribute to somatic symptom expression through maladaptive emotional regulation mechanisms. Mood stabilization may reduce functional neurological symptoms by modulating emotional reactivity and restoring neural network stability. The findings emphasize that functional neurological presentations should prompt careful assessment of underlying mood disorders, particularly bipolar spectrum conditions. Functional neurological symptoms may represent neuropsychiatric manifestations of affective instability in bipolar disorder. Integrated treatment combining mood stabilizers, antipsychotic medication, and psychotherapy can lead to meaningful clinical improvement. Recognition of the neuropsychiatric overlap between mood disorders and functional neurological conditions is essential for effective treatment planning.