Is musical hallucination an otological phenomenon? a review of the literature

Drug-induced musical hallucination

Musical hallucination is a rare perceptual phenomenon wherein individuals hear music in the absence of external auditory stimuli. This phenomenon occurs across diverse medical conditions and can be triggered by some drugs. The underlying mechanism of drug-induced hallucination is unknown. This study explores drug-induced musical hallucination through a literature review, aiming to investigate its pathophysiology and potential treatment modalities. A literature search was conducted until January 2024 using databases PubMed, WorldCat, Google Scholar, and DOAJ, with keywords "drugs induced musical hallucination" or "drugs" combined with "musical hallucination." The search yielded 24 articles which met inclusion criteria, encompassing 27 cases. The average patient age was 58.3 years, with 67.9% females. Prevalent conditions among cases included hearing impairments, psychiatric disorders, cancers, and neurodegenerative conditions. Common trigger drugs comprised antidepressants, opioids, anti-Parkinson drugs, ketamine, and voriconazole. Musical hallucination descriptions varied widely, and 6 patients reported concurrent visual hallucinations. The onset of symptoms ranged from 75 min to 240 days. Treatment strategies included termination of trigger drugs, dosage reduction, alteration of administration routes or formula, switching to similar drugs, or addition of antidepressants, sedatives, or atypical antipsychotic medications. Musical hallucinations completely disappeared in 24/27 (88.9%) patients but continued in 3/27 (11.1%) patients. The current study concludes that drug-induced musical hallucination may arise from altering neurotransmitter/receptor balance and intricate interactions between trigger drugs and underlying conditions.

A Systematic Review of Scientific Studies and Case Reports on Music and Obsessive-Compulsive Disorder

Obsessive-compulsive disorder (OCD) is a severe psychiatric disorder, which can be associated with music-related symptoms. Music may also be used as an adjunct treatment for OCD. Following the PRISMA guidelines, we performed a systematic literature review exploring the relationship between music and OCD by using three online databases: PubMed, the Web of Science, and PsycINFO. The search terms were "obsessive compulsive disorder", "OCD", "music", and "music therapy". A total of 27 articles were utilised (n = 650 patients/study participants) and grouped into three categories. The first category comprised case reports of patients with musical obsessions in patients with OCD. Most patients were treated with selective serotonin reuptake inhibitors (SSRIs) or a combination of an SSRI and another pharmacological or a non-pharmacological treatment, with variable success. Studies on the music perception of people with OCD or obsessive-compulsive personality traits represented the second category. People with OCD or obsessive-compulsive personality traits seem to be more sensitive to tense music and were found to have an increased desire for harmony in music. Three small studies on music therapy in people with OCD constituted the third category. These studies suggest that patients with OCD might benefit from music therapy, which includes listening to music.

Spontaneous brain activity underlying auditory hallucinations in the hearing-impaired

Auditory hallucinations, the perception of a sound without a corresponding source, are common in people with hearing impairment. Two forms can be distinguished: simple (i.e., tinnitus) and complex hallucinations (speech and music). Little is known about the precise mechanisms underlying these types of hallucinations. Here we tested the assumption that spontaneous activity in the auditory pathways, following deafferentation, underlies these hallucinations and is related to their phenomenology. By extracting (fractional) Amplitude of Low Frequency Fluctuation [(f)ALFF] scores from resting state fMRI of 18 hearing impaired patients with complex hallucinations (voices or music), 18 hearing impaired patients with simple hallucinations (tinnitus or murmuring), and 20 controls with normal hearing, we investigated differences in spontaneous brain activity between these groups. Spontaneous activity in the anterior and posterior cingulate cortex of hearing-impaired groups was significantly higher than in the controls. The group with complex hallucinations showed elevated activity in the bilateral temporal cortex including Wernicke's area, while spontaneous activity of the group with simple hallucinations was mainly located in the cerebellum. These results suggest a decrease in error monitoring in both hearing-impaired groups. Spontaneous activity of language-related areas only in complex hallucinations suggests that the manifestation of the spontaneous activity represents the phenomenology of the hallucination. The link between cerebellar activity and simple hallucinations, such as tinnitus, is new and may have consequences for treatment.

Musical Ear Syndrome: Prevalence and characteristics in cochlear implant bearers

INTRODUCTION

Musical Ear Syndrome (MES) is an uncommon phenomenon described as the perception of auditory musical sensations not corresponding to any external stimulus. It seems to be more frequent in case of profound hearing loss. Our objective was to evaluate prevalence, characteristics and risk factors in a population of cochlear implant patients.

METHODS

A retrospective study was conducted in cochlear implant patients, who were adult (>18 years) in 2020 and underwent cochlear implantation between 1993 and 2019. We analyzed the presence and characteristics of MES.

RESULTS

118 of the 358 patients (33%) perceived or had perceived auditory musical sensations: 71 (19.8%) before, 100 (28%) after, and 53 (14.8%) both before and after implantation. The musical auditory sensations were usually short and well-tolerated, resembling instrumental music, and occurring several times a day. Thirteen patients (11%) considered them intolerable. Fatigue was a triggering factor in 40 patients (33.9%). Personal and medical characteristics, type of implantation, make of implant, etiology and tinnitus did not emerge as risk factors. On the other hand, MES+ patients were significatively younger (56±17.4 years versus 61.9±17.9 years; P=0.0009). Despite the phenomenon, patients were satisfied with implant functioning and subjective auditory performance was not affected.

CONCLUSION

Prevalence of Musical Ear Syndrome was high in cochlear implant patients, and especially in younger subjects. It is essential to improve knowledge of this phenomenon.

Hallucinations: diagnosis, neurobiology and clinical management

Hallucinations are important diagnostic symptoms in schizophrenia, but also occur in other medical and neuropsychiatric conditions. Not all patients with hallucinations are psychotic. There has been a surge of interest in the topic of hallucinations, as new research data have begun to reveal their neurobiology. Hallucinogenic molecules may also serve as new scaffolds for the development of new psychotropic drugs. We searched and reviewed recent literature, focusing on the refinement of clinical management, which was inspired by new data regarding the neurobiology of hallucination subtypes. We concluded that the successful management of hallucinations depends on accurate differential diagnosis to identify subtypes, which would then determine the most appropriate treatment.

Auditory and visual hallucination prevalence in Parkinson's disease and dementia with Lewy bodies: a systematic review and meta-analysis

BACKGROUND

Non-motor features of Parkinson's disease (PD) and dementia with Lewy bodies (DLB), such as auditory hallucinations (AH), contribute to disease burden but are not well understood.

METHODS

Systematic review and random-effects meta-analyses of studies reporting AH associated with PD or DLB. Prevalence of visual hallucinations (VH) in identified studies meeting eligibility criteria were included in meta-analyses, facilitating comparison with AH. Synthesis of qualitative descriptions of AH was performed. PubMed, Web of Science and Scopus databases were searched for primary journal articles, written in English, published from 1970 to 2017. Studies reporting AH prevalence in PD or DLB were screened using PRISMA methods.

RESULTS

Searches identified 4542 unique studies for consideration, of which, 26 met inclusion criteria. AH pooled prevalence in PD was estimated to be 8.9% [95% confidence interval (CI) 5.3-14.5], while in DLB was estimated to be 30.8% (±23.4 to 39.3). Verbal hallucinations, perceived as originating outside the head, were the most common form of AH. Non-verbal AH were also common while musical AH were rare. VH were more prevalent, with an estimated pooled prevalence in PD of 28.2% (±19.1 to 39.5), while in DLB they were estimated to be 61.8% (±49.1 to 73.0). Meta-regression determined that the use of validated methodologies to identify hallucinations produced higher prevalence estimates.

CONCLUSIONS

AH and VH present in a substantial proportion of PD and DLB cases, with VH reported more frequently in both conditions. Both AH and VH are more prevalent in DLB than PD. There is a need for standardised use of validated methods to detect and monitor hallucinations.

Musical hallucinations, musical imagery, and earworms: A new phenomenological survey

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We conducted a phenomenological survey comparing musical hallucinations to other inner music.

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MH were more likely to be reported as externally located than other experiences.

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MH were less controllable and less familiar than imagery or earworms.

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MH were less likely to include lyrical content than other forms of inner music.

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Individuals with higher levels of musical expertise were less likely to report MH.

Musical hallucinations (MH) account for a significant proportion of auditory hallucinations, but there is a relative lack of research into their phenomenology. In contrast, much research has focused on other forms of internally generated musical experience, such as earworms (involuntary and repetitive inner music), showing that they can vary in perceived control, repetitiveness, and in their effect on mood. We conducted a large online survey (N = 270), including 44 participants with MH, asking participants to rate imagery, earworms, or MH on several variables. MH were reported as occurring less frequently, with less controllability, less lyrical content, and lower familiarity, than other forms of inner music. MH were also less likely to be reported by participants with higher levels of musical expertise. The findings are outlined in relation to other forms of hallucinatory experience and inner music, and their implications for psychological models of hallucinations discussed.

Functional auditory disorders

There are a number of auditory symptom syndromes that can develop without an organic basis. Some of these, such as nonorganic hearing loss, affect populations similar to those presenting with functional somatosensory and motor symptoms, while others, such as musical hallucination, affect populations with a significantly different demographic and require different treatment strategies. Many of these conditions owe their origin to measurably abnormal peripheral sensory pathology or brain network activity, but their pathological impact is often due, at least in part, to overamplification of the salience of these phenomena. For each syndrome, this chapter briefly outlines a definition, demographics, investigations, putative mechanisms, and treatment strategies. Consideration is given to what extent they can be considered to have a functional basis. Treatments are in many cases pragmatic and rudimentary, needing more work to be done in integrating insights from behavioral and cognitive psychology to auditory neuroscience. The audiology literature has historically equated the term functional with malingering, although this perception is, thankfully, slowly changing. These disorders transcend the disciplines of audiology, otorhinolaryngology, neurology and psychiatry, and a multidisciplinary approach is often rewarding.

Minds on replay: musical hallucinations and their relationship to neurological disease

The phenomenon of musical hallucinations, in which individuals perceive music in the absence of an external auditory stimulus, has been described sparingly in the literature through small case reports and series. Musical hallucinations have been linked to multiple associated conditions, including psychiatric and neurologic disease, brain lesions, drug effect, and hearing impairment. This study aimed to review the demographics of subjects with musical hallucinations and to determine the prevalence of neurological disorders, particularly neurodegenerative disease. Through the Mayo medical record, 393 subjects with musical hallucinations were identified and divided into five categories based on comorbid conditions that have been associated with musical hallucinations: neurological, psychiatric, structural, drug effect and not otherwise classifiable. Variables, including hearing impairment and the presence of visual and other auditory hallucinations, were evaluated independently in all five groups. The mean age at onset of the hallucinations was 56 years, ranging from 18 to 98 years, and 65.4% of the subjects were female. Neurological disease and focal brain lesions were found in 25% and 9% of the total subjects, respectively. Sixty-five subjects were identified with a neurodegenerative disorder, with the Lewy body disorders being the most common. Visual hallucinations were more common in the group with neurological disease compared to the psychiatric, structural, and not otherwise classifiable groups (P < 0.001), whereas auditory hallucinations were more common in the psychiatric group compared to all other groups (P < 0.001). Structural lesions associated with musical hallucinations involved both hemispheres with a preference towards the left, and all but two included the temporal lobe. Hearing impairment was common, particularly in the not otherwise classifiable category where 67.2% had documented hearing impairment, more than in any other group (P < 0.001). Those with an underlying neurodegenerative disorder or isolated hearing impairment tended to hear more persistent music, which was often religious and patriotic compared to those with a structural lesion, where more modern music was heard, and those with psychiatric disorders where music was mood-congruent. This case series shows that musical hallucinations can occur in association with a wide variety of conditions, of which neurological disease and brain lesions represent a substantial proportion, and that Lewy body disorders are the most commonly associated neurodegenerative diseases. A future prospective study would be helpful to further delineate an association between musical hallucinations and neurodegenerative disease.

Musical hallucinations: review of treatment effects

BACKGROUND

Despite an increased scientific interest in musical hallucinations over the past 25 years, treatment protocols are still lacking. This may well be due to the fact that musical hallucinations have multiple causes, and that published cases are relatively rare.

OBJECTIVE

To review the effects of published treatment methods for musical hallucinations.

METHODS

A literature search yielded 175 articles discussing a total number of 516 cases, of which 147 articles discussed treatment in 276 individuals. We analyzed the treatment results in relation to the etiological factor considered responsible for the mediation of the musical hallucinations, i.e., idiopathic/hypoacusis, psychiatric disorder, brain lesion, and other pathology, epilepsy or intoxication/pharmacology.

RESULTS

Musical hallucinations can disappear without intervention. When hallucinations are bearable, patients can be reassured without any other treatment. However, in other patients musical hallucinations are so disturbing that treatment is indicated. Distinct etiological groups appear to respond differently to treatment. In the hypoacusis group, treating the hearing impairment can yield significant improvement and coping strategies (e.g., more acoustic stimulation) are frequently helpful. Pharmacological treatment methods can also be successful, with antidepressants being possibly more helpful than antiepileptics (which are still better than antipsychotics). The limited use of acetylcholinesterase inhibitors has looked promising. Musical hallucinations occurring as part of a psychiatric disorder tend to respond well to psychopharmacological treatments targeting the underlying disorder. Musical hallucinations experienced in the context of brain injuries and epilepsy tend to respond well to antiepileptics, but their natural course is often benign, irrespective of any pharmacological treatment. When intoxication/pharmacology is the main etiological factor, it is important to stop or switch the causative substance or medication.

CONCLUSION

Treatments for musical hallucinations tend to yield favorable results when they target the main etiological factor of these phenomena. 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. There is also a need to standardize the assessment of treatment responses, and document long-term follow up.

Musical hallucinations treated with acetylcholinesterase inhibitors

Musical hallucinations are relatively rare auditory percepts which, due to their intrusive nature and the accompanying fear of impending mental decline, tend to cause significant distress and impairment. Although their etiology and pathophysiology appear to be heterogeneous and no evidence-based treatment methods are available, case reports indicate that acetylcholinesterase inhibitors may yield positive results in patients with comorbid hearing loss. We present two female patients (aged 76 and 78 years) both of whom suffered from hearing impairment and practically incessant musical hallucinations. Both patients were successfully treated with the acetylcholinesterase inhibitor rivastigmine. Based on these two case descriptions and an overview of studies describing the use of acetylcholinesterase inhibitors in similar patients, we discuss possible mechanisms and propose further research on the use of acetylcholinesterase inhibitors for musical hallucinations experienced in concordance with hearing loss.

Musical hallucinations in a patient with presbycusis: a case report

BACKGROUND

Musical hallucinations are a rare subtype of auditory hallucination characterized by the perception of musical sounds, instrumental music, or songs. They are most commonly seen in older women with age-related hearing loss but are also associated with neurologic and psychiatric conditions. The underlying pathophysiology is poorly understood and likely multifactorial.

CASE REPORT

A 74-year-old woman presented with subjective hearing loss 2-3 years in duration with a recent development of hearing continuous patriotic and children's songs playing in her head. After extensive interviewing and the documentation of a normal otologic/comprehensive head and neck examination, audiologic evaluation revealed evidence of a symmetric high-frequency sensorineural hearing loss consistent with presbycusis. She was counseled on the use of ambient noise and offered a trial of binaural hearing amplification.

CONCLUSION

The diagnosis of musical hallucinations requires the consideration of numerous possible etiologies. Treatment varies widely, but many patients improve with the use of ambient noise and hearing amplification. Lack of response requires the consideration of pharmacologic treatments such as anticonvulsants, antipsychotics, and anticholinesterases. It is important to reassure patients with a nonpsychiatric etiology that use of these drugs does not imply psychiatric illness.

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.

The beneficial effect of escitalopram on obsessive-compulsive-related musical hallucinations in elderly patients with hearing impairment: a case series

Musical hallucinations (MHs), characterized by the hearing of tunes, melodies, or songs, is a relatively under-recognized phenomenon among elderly individuals with hearing impairment. In some patients, MHs represent a complex psychopathological phenomenon, hallucinatory in content and obsessive-compulsive (OC) in form, justifying trial with an antiobsessive agent. In the present case series, we describe our clinical experience with escitalopram in six (two men, four women; age 74-85 years) elderly individuals with OC-related MH and hearing impairment who did not respond to previous antipsychotic treatment. Switch to escitalopram (mean 12.5 mg) led to a substantial improvement in the MH symptom severity, as reflected in a decrease in the global score of the Yale-Brown Obsessive-Compulsive Scale adapted to OC-related MH (scores before escitalopram, 13.2±0.9; after 12 weeks of treatment, 7.8±2.8; P<0.01). Escitalopram was well tolerated, and the only detected side effects, nausea and headache, were mild and transient. If confirmed in controlled trials, escitalopram and probably other selective serotonin reuptake inhibitors may be a therapeutic option in elderly individuals with OC-related MH.

The mind with a radio of its own: a case report and review of the literature on the treatment of musical hallucinations

Musical hallucinations (MH) have been labeled Oliver Sacks syndrome, and in the majority of cases, they occur in the context of a hearing loss. In these instances, they have been described as auditory Charles Bonnet syndrome because they are thought to represent a cortical release phenomenon. Patients with MH tend to have intact reality testing, and as such, the condition may also be described as musical hallucinosis. The temporal course of MH is variable, but given that they may improve or remit with time, education on their benign nature is often sufficient. MH also may improve when hearing loss is reversed. The use of ambient noise potentially ameliorates mild to moderate MH; however, where this is insufficient, somatic treatments may be considered. Case reports have documented successful use of low-dose antiepileptics, atypical antipsychotics and donepezil. We present a case of a 52-year-old man who received only partial relief from serial treatment with several psychotropic agents. He developed major depression with suicidal ideation in the context of persistent, intrusive MH that were refractory to several medication trials, and whereas a course of electroconvulsive therapy led to remission of depressive and suicidal symptoms, it provided only transient relief of his MH. In this article, we also provide a review of the literature on the neurobiology and treatment of MH.

A brain basis for musical hallucinations

The physiological basis for musical hallucinations (MH) is not understood. One obstacle to understanding has been the lack of a method to manipulate the intensity of hallucination during the course of experiment. Residual inhibition, transient suppression of a phantom percept after the offset of a masking stimulus, has been used in the study of tinnitus. We report here a human subject whose MH were residually inhibited by short periods of music. Magnetoencephalography (MEG) allowed us to examine variation in the underlying oscillatory brain activity in different states. Source-space analysis capable of single-subject inference defined left-lateralised power increases, associated with stronger hallucinations, in the gamma band in left anterior superior temporal gyrus, and in the beta band in motor cortex and posteromedial cortex. The data indicate that these areas form a crucial network in the generation of MH, and are consistent with a model in which MH are generated by persistent reciprocal communication in a predictive coding hierarchy.

Treatment of anxiety from musical obsessions with a cognitive behaviour therapy tool

Musical obsessions and hallucinations are disturbing experiences of repeating internal music. Antipsychotic medication can sometimes reduce these symptoms but can also trigger or augment them. We report the case of a female patient with schizophrenia with drug-resistant obsessive musical hallucinations. The patient volunteered to participate in a 9-month pilot study to follow the development of the condition using an involuntary music and mood inventory. The patient perceived benefits from the intervention, including reduced anxiety, increased feeling of being in control and understanding the condition better. Findings from this case study suggest that cognitive therapy can be a useful complementary method of care for persons with musical obsessions. The presented tool requires further investigations among those with this rare condition.

Musical ear syndrome in adult cochlear implant patients

OBJECTIVE

Except for a single case report, musical ear syndrome in cochlear implantees has not been studied. We aimed to study the prevalence and nature of musical ear syndrome among adult cochlear implant patients, as well as the effect on their emotional well-being. STUDY DESIGN, PATIENTS AND INTERVENTION: A cross-sectional survey of patients aged 18 years and above who had received cochlear implants for profound hearing loss between 1997 and 2010.

RESULTS

Of the 82 patients studied, 18 (22 per cent) were found to have experienced musical ear syndrome. Seven and 11 patients had musical ear syndrome prior to and after cochlear implantation, respectively. The character of musical ear syndrome symptoms was described as instrumental music (n = 2), singing (6) or both (10). Fourteen patients reported an adverse emotional effect, with three expressing ‘intolerance’.

CONCLUSIONS

In this study, 22 per cent of cochlear implantees experienced musical ear syndrome. These symptoms affected patients’ emotional state, but most coped well. Musical ear syndrome can occur prior to and after cochlear implantation.

A comprehensive review of auditory verbal hallucinations: lifetime prevalence, correlates and mechanisms in healthy and clinical individuals

Over the years, the prevalence of auditory verbal hallucinations (AVHs) have been documented across the lifespan in varied contexts, and with a range of potential long-term outcomes. Initially the emphasis focused on whether AVHs conferred risk for psychosis. However, recent research has identified significant differences in the presentation and outcomes of AVH in patients compared to those in non-clinical populations. For this reason, it has been suggested that auditory hallucinations are an entity by themselves and not necessarily indicative of transition along the psychosis continuum. This review will examine the presentation of auditory hallucinations across the life span, as well as in various clinical groups. The stages described include childhood, adolescence, adult non-clinical populations, hypnagogic/hypnopompic experiences, high schizotypal traits, schizophrenia, substance induced AVH, AVH in epilepsy, and AVH in the elderly. In children, need for care depends upon whether the child associates the voice with negative beliefs, appraisals and other symptoms of psychosis. This theme appears to carry right through to healthy voice hearers in adulthood, in which a negative impact of the voice usually only exists if the individual has negative experiences as a result of their voice(s). This includes features of the voices such as the negative content, frequency, and emotional valence as well as anxiety and depression, independently or caused by voices presence. It seems possible that the mechanisms which maintain AVH in non-clinical populations are different from those which are behind AVH presentations in psychotic illness. For example, the existence of maladaptive coping strategies in patient populations is one significant difference between clinical and non-clinical groups which is associated with a need for care. Whether or not these mechanisms start out the same and have differential trajectories is not yet evidenced. Future research needs to focus on the comparison of underlying factors and mechanisms that lead to the onset of AVH in both patient and non-clinical populations.

Tinnitus and musical hallucinosis: the same but more

While tinnitus can be interpreted as a simple or elementary form of auditory phantom perception, musical hallucinosis is a more complex auditory phantom phenomenon not only limited to sound perception, but also containing semantic and musical content. It most often occurs in association with hearing loss. To elucidate the relation between simple and complex auditory phantom percepts a source localized electroencephalography (EEG) study is performed. The analyses showed in both simple and complex auditory phantoms an increase in theta-gamma activity and coupling within the auditory cortex that could be associated with the thalamocortical dysrhythmia model. Furthermore increased beta activity within the dorsal anterior cingulate cortex and anterior insula is demonstrated, that might be related to auditory awareness, salience and its attribution to an external sound source. The difference between simple and complex auditory phantoms relies on differential alpha band activity within the auditory cortex and on beta activity in the dorsal anterior cingulate cortex and (para)hippocampal area. This could be related to memory based load dependency, while suppression within the primary visual cortex might be due the presence of a continuous auditory cortex activation inducing an inhibitory signal to the visual system. Complex auditory phantoms further activate the right inferior frontal area (right sided Broca homolog) and right superior temporal pole that might be associated with the musical content. In summary, this study showed for the first time that simple and complex auditory phantoms might share a common neural substrate but differ as complex auditory phantoms are associated with activation in brain areas related to music and language processing.

Prevalence of musical hallucinations in patients referred for audiometric testing

OBJECTIVE

To assess the prevalence of musical hallucinations in patients referred for audiometric testing and to analyze associations with age, sex, degree of hearing loss, asymmetrical hearing loss, and tinnitus.

METHODS

Patients referred for audiometric testing underwent a semi-structured interview on tinnitus and musical hallucinations.

RESULTS

Out of 194 patients, most of whom had mild to moderate hearing loss, seven (3.6%) had musical hallucinations. Significant associations were found with female sex and predominant left-sided hearing impairment, but not with age, severity of hearing loss, or tinnitus.

CONCLUSION

This study offers no evidence that age is a risk factor. Musical hallucinations seem to be prevalent in women with predominant left-sided hearing impairment.

Musical hallucination following whiplash injury: case report and literature review

INTRODUCTION

A musical hallucination is defined as a form of auditory hallucination characterised by the perception of music in the absence of external acoustic stimuli. It is infrequently cited in the literature, although population studies suggest a greater prevalence. The aetiology of this unusual disorder remains unclear.

CASE REPORT

A 70-year-old man with acquired hearing loss suffered a whiplash injury in a low-speed road traffic accident, and subsequently presented with bilateral 'tinnitus.' On closer questioning, he described hearing orchestral music. There was no evidence of psychosis, delirium or intoxication, and the patient was managed expectantly.

CONCLUSION

This patient represents the first published case of musical hallucination precipitated by whiplash injury. We explore the possible pathophysiological underpinnings of musical hallucination and highlight the need for a greater awareness of this disorder. A management strategy is suggested.

Neurofunctional assessment in a stroke patient with musical hallucinations

We reported a case of an elderly female patient affected by musical hallucinations (MHs) as the unique symptom of a right temporal ischemic stroke. A functional magnetic resonance imaging examination was performed in the patient and in five age- and sex-matched normal controls (NC) to detect the complex neural substrate subserving MHs in such a context. Although an activation pattern involving the primary auditory cortex and the temporal associative areas bilaterally was found in the patient and NC, a significant increased activation mostly located in right temporal cortex (in the ischemic area), was observed in the patient. Further functional neuroimaging studies should be performed to detect the complex neural pathways underlying MHs and to find out differences between these hallucinations and real music perception.