Complex auditory musical hallucinations with ambivalent feelings

Background

A hallucination is a perception of a sensory stimulus where none exist. Auditory hallucinations are traditionally associated with schizophrenia but can also arise from injury to any portion of the peripheral and central auditory pathways, described in patients with Alzheimer’s disease and patients with epilepsy and healthy individuals.1 2 They can be simple (static, beeping and humming) or complex (voices and music).

Musical hallucinations (MH) are complex auditory hallucinations that comprise tunes, songs, harmonics, timbres, melodies and rhythms, which are perceived without musical stimuli3 and were first described in 1846 by Jules Baillarger (1806–1891).4 They can be repetitive and stereotyped—stable MH—or convoluted and susceptible to remodelling—complex MH.3 4 Sacks and Blom described different variants. The prevalence of MH was described as 0.16% of general psychiatric admissions5 and as high as 2.5% in older patients with hearing impairment,6 but it is overall considered a rare phenomenon and the exact prevalence is not known. The mean age of onset of MH is described to be 56 years, with the majority of patients being female.7

Occasionally, they are associated with secondary delusions and accusing others of being responsible for the music, which can severely disable and lead to impaired quality of life and significant distress.8 However, according to Berrios, MH is perceived as a pleasant experience by most patients.9 This distinctive significance and pleasant nature of the hallucinations may be related to their heterogeneous aetiologies. Since most patients with MH experience music familiar to them, one can assume that the underlying processes represent abnormal activation of a musical memory circuitry.10 Recent functional imaging studies unveiled some brain areas that may explain MH.11 12 However, the neural circuitry behind MH is yet to be fully mapped.

The evidence on the treatment of MH is also scarce. Auditory Charles Bonnet syndrome is known to remit following the improvement of hearing.13 Case studies report successful treatment of MH with antipsychotics, antidepressants and cognitive enhancers depending on the aetiology.14 According to a review of MH treatment effects by Coebergh et al, ‘treatments for musical hallucinations tend to yield favourable results when they target the main etiological factor of these phenomena’. However, according to the previous authors, ‘there is a need to establish the natural course of musical hallucinations, their response to non-pharmacological treatments, and their effects on the patient’s quality of life’. Aetiological factors may be, however, multiple, entangling the understanding of the natural history of the symptom, the symptom itself and the respective treatment.

Therefore, we describe a rare case of a patient with ambivalent feelings regarding complex MH and discuss their aetiology and treatment.

Case presentation

A 78-year-old caucasian woman, illiterate, widow for 15 years, retired for 25 years (had previously worked as a housewife), living with her nephew and one of her three daughters, with a personal medical background of hypertension and diabetes mellitus type 2 was diagnosed with a bilateral hearing loss; she had no relevant familiar psychiatric or medical history. Figures 1–3 show the patient’s tympanogram, reflexes and audiogram, respectively. Pure-tone audiogram showed a bilateral and symmetric moderate to severe sensorineural hearing loss. The tympanogram was type As and stapedial reflexes were present bilaterally.

A year after the diagnosis of hearing impairment, she was referenced to geriatric psychiatry for changes in her behaviour and cognitive dysfunction within 2 years of evolution. Besides cognitive dysfunction, she presented erotomanic delusion regarding her neighbour and complex MH. She described it as hearing her neighbour singing a familiar church song along with bells in the background, progressively louder during the day. Sometimes, the song was interrupted with auditory verbal hallucinations of her neighbour’s voice making sexual and provocating comments (in the second person) and her neighbour talking to her daughter and spouse, making comments about her (in the third person). Although she was catholic, she did not go to the church for many years, and she never enjoyed music overall.

Moreover, these symptoms were associated with marked distress, especially at night. Interestingly, she felt ambivalent toward her neighbour’s voice: sometimes ‘his voice’ was felt as pleasant, other times distressing and disturbing to her. Listening to music allowed the patient to slightly decrease these phenomena, as she could not identify other alleviators that could change the intensity or the frequency of these auditory hallucinations.

She was then admitted to a psychiatric inpatient unit, where she underwent a complete diagnostic investigation.

Investigations

By the time of admission, a Mini-Mental State Examination (MMSE) was performed, for which she obtained 23/30 (orientation 8/10; registration 3/3; attention and calculation 4/5; recall 2/3; language 6/8 and copying 0/1). Besides cognitive impairment, the patient did not present other significant remarks on the neurologic (including tremor, motricity and sensitivity) and mental state examination. During hospitalisation, the patient completed a blood workup without any findings and underwent a computed tomography (CT) of the brain (figure 4) that detected small right nucleocapsular and bilateral external capsules hypodensities. These are of presumed vascular aetiology, which are associated with diffuse accentuation of the relative hypodensity of the periventricular white substance, which translates to a probable pattern of chronic microangiopathic leucoencephalopathy. The electroencephalogram excluded epileptiform activity. The clinical team did not perform a neuropsychological evaluation or MRI of the brain. By the time of discharge, the patient obtained the same MMSE results as at the admission.

Differential diagnosis

Overall causes for MH include psychiatric disorders (mainly depression), neurodegenerative disorders, hearing impairment, epilepsy (mainly ictal phenomena; auras with musical features are rare),15 brain tumours, head injury, encephalitis, multiple sclerosis, substance intoxication,7 16 thalamic infarcts, subarachnoid haemorrhage, abnormalities of the auditory cortex,17 18 post-concussive syndrome, amyloid beta angiitis, migraine, posterior reversible encephalopathy syndrome and multiple system atrophy.7

Although MH usually occur in advanced age and hearing impairment is the most commonly identified predisposing condition, only a minority of these patients develops MH. In this patient, social isolation, cognitive dysfunction, vascular risk factors and multiple medications might be additional contributing factors. We believe all of these factors are contributing to the psychopathology of this patient. In addition, the characteristics of these complex hallucinations might reflect the heterogeneous aetiology: church choral music are typical of neurodegenerative disorders and auditory Charles Bonnet syndrome19 20; auditory verbal hallucinations in the second and third person and erotomanic delusion are typical of schizophrenia and other psychotic spectrum disorders. However, since the latter hypothesis is an exclusion diagnosis according to the main classification systems,21 22 the most probable diagnosis is dementia (or major cognitive disorder), vascular or mixed aetiology and psychotic symptoms.

Treatment

MH occurring as part of a psychiatric disorder or epilepsy tend to respond well to psychopharmacological treatments targeting the underlying disorder.23 The multidisciplinary team, including psychiatrists, a neurologist and an internist, discussed the treatment. Despite unsuccessful treatment with olanzapine, risperidone and haloperidol, she obtained a gradual reduction of dynamism of the erotomanic delusion and the auditory hallucinations, with the following medication, for which she was discharged: clozapine 100 mg, zonisamide 100 mg, donepezil 5 mg and memantine 20 mg. The patient did not tolerate oxcarbazepine due to unbalance and risk of fall. Our patient obtained only a reduction of dynamism of symptoms with an antipsychotic, an anticonvulsant and two antidementials, supporting our hypothesis of an underlying neural circuitry behind MH that is yet to be unveiled.

Outcome and follow-up

At discharge, she was in remission of the psychotic symptoms and kept an ambulatory follow-up. The clinical team carried out psychoeducation on the patient and her nephew. During the first follow-up visit after hospitalisation, the patient kept the erotomanic delusion and the complex auditory hallucinations (including music) directed at her neighbour, although with less dynamism and without behavioural impact, with partial insight. Several appointments after, the patient died; the cause of death is not known.