Chronic auditory hallucinosis and paranoid psychosis in a man with a history of right temporal lobe lesion and alcohol abuse
In 2004 a 50-year-old man was referred to the psychiatric service with adjustment problems and mild anxiety. He also complained of forgetfulness, but no objective memory deficit could be identified on this occasion. In 2006 the patient was re-referred with distressing auditory hallucinations, experienced inside his head in second and third person, and frightening persecutory ideas. He also complained of deteriorating memory functions. There was evidence of excessive use of alcohol, probably going back for several years. According to his medical records, the patient sustained a head injury 6 years previously, leading to a right fronto-temporal subdural haematoma and right temporal lobe contusion. A dementing illness was suspected, and, in 2009, the patient was referred to clinical neurology and neuropsychiatry, for further investigation.
On clinical interview the patient reiterated his auditory hallucinations and reported delusions of persecution and reference consistent with a paranoid psychosis. MRI brain scan showed scarring in the right temporal lobe, and EEG sharp waves over the temporal lobes. SPECT imaging showed reduced perfusion in the medial temporal region on the right. Neuropsychological assessment revealed significant cognitive impairment, particularly for verbal and visual memory. There was additional patchy evidence of executive dysfunction, and evidence of a decline in general intellectual functioning. Review of the literature indicates an association between lesions to the right temporal lobe and the development of auditory hallucinosis. Our patient might have been particularly vulnerable to this complication of brain injury due to his abuse of alcohol, which can also lead to the development of auditory hallucinosis. The cognitive impairment with an emphasis on episodic memory is likely to be the consequence of alcohol induced brain damage, which again may have been aggravated by the traumatic injury to the right temporal lobe.