Monoaural musical hallucinations caused by a thalamocortical auditory radiation infarct: a case report

INTRODUCTION Musical hallucinations are complex auditory perceptions in the absence of an external acoustic stimulus and are often consistent with previous listening experience. Their causation can be classified as associated with either psychiatric disorders, such as schizophrenia, or organic disorders, such as epilepsy or sensorineural deafness. Non-epileptic musical hallucinosis due to lesions of the central auditory pathway, especially of the thalamocortical auditory radiation, is rare. CASE PRESENTATION We describe the case of an 85-year old ethnic Chinese woman with a history of transient ischemic attacks and chronic bilateral hearing impairment, who experienced an acute onset of left unilateral musical hallucinations. Our patient did not experience any psychiatric symptoms and there was no other neurological deficit. Pure tone audiometry revealed bilateral hypacusis and magnetic resonance imaging revealed a right non-dominant hemisphere sublenticular lacunar infarct of the thalamocortical auditory radiation. Our patient was managed expectantly and after three months her symptoms subsided spontaneously. CONCLUSION We propose that all patients with monoaural musical hallucinations have brain imaging to rule out a central organic cause, especially within the non-dominant hemisphere, regardless of the presence of a hearing impairment.