Balancing Efficacy and Safety: Transcranial Direct Current Stimulation as an Adjunctive Intervention for Persistent Auditory Verbal Hallucinations in a Case of Schizophrenia and Seizure Disorder with Incomplete Hippocampal Inversion

Incomplete hippocampal inversion (IHI) is associated with epilepsy and schizophrenia, often leading to persistent audi tory verbal hallucinations (AVH). This case study discusses a 23-year-old with diagnosed with schizophrenia, intellectual disability, and a seizure disorder, having AVH non-responsive to multiple antipsychotics. Magnetic resonance imaging indicated left hippocampal IHI. In view of the increased risk of seizure with clozapine, transcranial direct current stim ulation (tDCS) was administered, targeting the left temporoparietal junction using cathodal stimulation and left dorso lateral prefrontal cortex using anodal stimulation. Following 20 sessions over 10 days, AVH significantly improved, with Scale for the Assessment of Positive Symptoms and Auditory Hallucination Rating Scale scores reducing by over 70%, maintaining at a 3-month follow-up. This case highlights tDCS as an effective adjunctive treatment for AVH in schizophrenia with structural brain abnormalities, emphasizing the need for further research into tDCS effects on hippo campal-temporoparietal connectivity.