Altered Cerebral Perfusion and the Emergence of Schneiderian First-Rank Symptoms Following Modified Electroconvulsive Therapy in Late-Life Depression

Electroconvulsive therapy (ECT) is a well-established treatment for severe or treatment-resistant major depressive disorder and schizophrenia, often leading to rapid symptom improvement. However, ECT can rarely cause adverse psychological effects, including new-onset auditory hallucinations. We present the case of a 71-year-old woman with major depressive disorder who showed rapid clinical improvement following ECT, along with restoration of cerebral blood flow in the frontotemporal and parietal regions as shown by neuroimaging. Despite remission of depressive symptoms, she developed de novo auditory hallucinations with a running commentary, classified as Schneiderian first-rank symptoms, which persisted for several months despite continued treatment with olanzapine. Unlike previously reported cases in which hallucinations resolved shortly after completion of ECT, this case highlights a rare instance of persistent hallucinations that emerged during the same period as cerebral perfusion changes but cannot be interpreted as causally or associatively related based on the available data. Although perfusion improvement was observed, these imaging findings should be regarded solely as descriptive observations rather than indicators of a mechanistic link. To our knowledge, this is the first report to describe the coexistence of ECT-induced cerebral blood flow changes and new-onset auditory hallucinations; however, no meaningful clinical-biological connection can be inferred from this single case. This finding underscores the need for further investigation into the neurobiological mechanisms underlying rare ECT-related side effects to improve patient management and safety.