1 069 J'ournal of Neurology, Neurosurgery, and Psychiatry 1992;55:1069-1073 Transient musical hallucinosis of central origin: a review and clinical study P Paquier, P van Vugt, P Bal, P Cras, P M Parizel, J van Haesendonck, W Creten, J Martin J Abstract A 52 year old, right handed, hearing impaired woman was admitted with headache and neck stiffness. The only neuropsychological symptom was transient auditory perceptions in the left ear, which were musical, seemed familiar and were not influenced by verbal communication. CT and MRI showed a right subarachnoid haemorrhage, while brainstem auditory evoked potentials failed to reveal a brainstem lesion. In patients with organic cereunilateral auditory bral disease, hallucinations (AHs) may indicate a lesion in the contralateral hemisphere. However, according to this review the type of AHs (verbal versus musical) is not consistendy associated with a cerebral lesion on either side. Antwerp University Hospital, Edegem, Belgium Division of Neurolinguistics (Departments of Neurology and ENT) P Paquier Department of Radiology P M Parizel University of Antwerp (UIA) Unit of Neurolinguistics (Department of Romance Philology) P van Vugt Didascalia (Department of Didactics) P Bal Department of Neurology (Born-Bunge Foundation) P Cras J J Martin Department of ENT J van Haesendonck University of Antwerp (RUCA) Laboratory for Medical Biophysics W Creten Correspondence to: P Paquier, Division of Neurolinguistics, Antwerp University Hospital, Wilrijkstraat 10, B-2650 Edegem, Belgium. Received 5 November 1991 and in revised form 27 January 1992. Accepted 6 February 1992 Bryant55 stated that unilateral AHs are unquestionably due to unilateral ear disease. On the other hand, Bergman56 and Tanabe et al'5 assumed that, in patients with organic brain disease, unilateral AHs could be considered a reliable indication of contralateral cerebral pathology. Berrios57 emphasised the important role played by the non-dominant hemisphere in the development of AHs of the musical type. We studied a hearing impaired patient who developed a transient unilateral auditory hallucinosis in her ear, ffter a contralateral right subarachnoid haemorrhage. Case report A 52 year old, right handed woman of normal intelligence, presented with a previous medical history of multiple streptococcal sore throats complicated by acute rheumatic arthritis in (J Neurol Neurosurg Psychiatry 1992;55:1069-1073) childhood, a bilateral asymmetrical hearing loss, common migraine attacks for several Auditory hallucinations (AHs) are auditory years, a thrombo-embolic small intestinal perceptions that occur in the absence of a infarct at the age of 49, gastrointestinal blood corresponding external acoustic stimulus.' The loss three months before the current event, a subject may or may not be fully aware of their cardiac murmur based on mitral and aortic imaginary nature.24 AHs may be either ele- insufficiency, and hypertension. She admitted mentary, for example, tinnitus, whistles, buzz- misuse of ergotalkaloids in the past. There was ing; or complex, such as music, voices or no history of overconsumption of alcohol. In July 1988, she developed sudden right spoken words.5 6 AHs may occur in isolated form, but some are associated with other temporal headaches, progressively increasing hallucinations, for instance, visual or tac- and accompanied by an aching stiffness of the tile.7-'2 AHs may be perceived in either, or cervical spine. She looked ill, her right eye was both ears.3'-5 AHs have been described in slightly proptotic and she could not move her different conditions: several psychiatric dis- neck without great pain. She complained of orders,' 141630 prolonged alcoholism, 31-35 paresthesiae in both upper limbs. Her blood intoxication with drugs and other chemical pressure was 200/70 mm Hg. The rest of the 1 agents, 361 hypertension,42 several neuro- neurological examination was normal. Paralogical disorders including migraine4344 and cetamol made her feel more comfortable. Two days later, she started complaining of epilepsy., 42 45-49 and ear diseases 13 16 50-53 The exact origin of AHs remains unclear. From a hearing music in her left ear. The music began physiological and biochemical viewpoint, AHs suddenly at 11 pm, and was of such clarity that the patient thought that the radio was playing may result from an abnormal brain excitability in the hospital corridor. After asking the nurses or a central disinhibitory factor, and from defective neurotransmission mechanisms.' 6 about the noise and then lying down on her Some investigators'3 50-52 claim that neural or better ear, she realised that the music was end organ disease alone is sufficient to produce coming from inside her head. From that AHs, thus postulating sensory deprivation to moment, she was always aware of the hallucibe the primary neurophysiological mechanism. natory character of the musical perceptions. Others 6 53 maintain that a combination of She described the music as popular classical, peripheral and central dysfunction is comprising orchestral arrangements with occasional vocals. She always recognised the tunes, required. Hecaen and Ropert42 argued that lateralisa- which never bored her, although she sometion of AHs has no localising value in hal- times wished for respite. They varied, and did lucinosis-that is, organic hallucinations of not repeat themselves constantly. On rare central origin, but would consistently implicate occasions the contents of the hallucinations the worst ear when of otopathic origin.54 were distorted. Occasionally she heard bells 1070 Figure Sagittal Tl-weighted spin echo (short TRishort TE) MRI through the right sylvian fissure reveals a mild increase in signal intensity, presumably representing subacute haemorrhage (arrows). The high signal intensity represents methemoglobin formation. Paquier, van Vugt, Bal, Cras, Parizel, van Haesendonck, Creten, Martin chiming. She heard music when she awoke index of 45 dB, and a mixed perceptiveduring the night, and when talking. The conductive hearing loss on the right, Fletcher hallucinations occurred consistently, whether index, 90 dB. Otoscopy revealed a normal left or not she used the hearing aid in her left ear. drum and a posterior retracted drum on the Only twice did she experience verbal hallucina- right with a suspected incudostapedial dislocations, comprising unknown voices speaking tion. However, her otological status had whole sentences which she could not under- remained unchanged since 1986. stand. She did not experience hallucinations in Neurolinguistic and neuropsychological other modalities. A few days later, the percep- examinations at the time of the hallucinations tions lessened in intensity, and were sometimes failed to reveal any signs of aphasia, apraxia, superseded by the ticking of a clock. The agnosia, visuospatial disorders or hemispatial hallucinations disappeared gradually over the neglect. The Sound Lotto Test58 excluded following days and three weeks after admis- auditory agnosia. The patient had an IQ of 1 17 sion, the patient was free of them. On re- on Raven's59 standard progressive matrices. examination three months later, she had no complaints and her neurological status was Discussion normal. Clinical investigation at the time of the The patient's peri-acute neuropsychological hallucinations found no evidence of major symptomatology consisted of auditory hallucipsychiatric disorders. Laboratory tests did not natory perceptions in the absence of other major disorders of the higher mental functions. disclose any intoxication. A CT examination performed two days after A comparison of her clinical picture, as well as demonstrated the hyperdense personal and medical histories, with the differadmission aspect of the right sylvian fissure and the right ent conditions that may cause AHs, allowed us parietal sulci, presumably reflecting localised to reject all but two. Elementary and complex AHs have been subarachnoid haemorrhage (SAH). A cerebral angiography showed vasospasm of the oper- reported in patients with a long history of culofrontal branches of the right middle cere- progressive, sensorineural deafness in one or bral artery. An aneurysm could not be both ears, together with tinnitus. They are identified. CT scans obtained 10 and 20 days often of acute onset at the time of a further loss after admission showed progressive disappear- of hearing, and are experienced predominantly ance of the hyperdense aspect of the right in the deaf or deafer ear.5l 54 60 61 They are not sylvian fissure. CT also disclosed the presence associated with a psychosis."3 57 AHs in deafof old, bilateral capsuloputaminal lacunar ness seem to be permanent.52 53 6263 It appears infarcts. MRI revealed an area of increased that musical hallucinations may disappear after signal intensity on a sagittal Tl-weighted some time, and be replaced by short but image through the right sylvian fissure, indicat- repetitive musical phrases, like the noise of a scratched record.57 Transitory, unilateral AHs ing subacute localised SAH (fig). The day before the onset of the musical have been mentioned in cases of acute ear hallucinations, the EEG showed a symmetrical disease. However, they parallel the evolution of recording which was within normal limits. the lesion, and gradually disappear on recovThere was no evidence of epileptic activity nor ery.54 Our patient had suffered progressive bilatof intoxication. Brainstem auditory evoked potentials (BAEP) at the time of the musical eral hearing loss for many years, greater on the right, not associated with tinnitus. ENT invesperceptions were normal. Ear, nose and throat examination at the time tigation during admission failed to disclose an of the auditory phenomena revealed a percep- acute lesion, and neither otoscopic changes nor tive hearing loss on the left with a Fletcher further hearing loss were found when compared with the previous examination. In other words, our patient's perceptions did not occur at the time of a further decrement in hearing. The auditory phenomena progressively disappeared over a period of two weeks, which is not compatible with the persistent nature of otogenic AHs. As our patient did not present with an acute ear disease, the gradual disappearance of her musical perceptions does not fit transitory AHs of otopathic origin. Moreover, she experienced the musical perceptions in her better ear, which is quite unusual in AHs of otopathic origin.545564 Finally, otogenic AHs seem to respond favourably to treatment with a hearing aid,606' whereas our patient's auditory perceptions were not altered or abolished by her prosthesis. Consequently, these findings indicate that the origin of our patient's auditory perceptions cannot be reduced to a mere otopathy. Transient AHs may also be encountered in several cerebral conditions.'7 15 42 45 49 56 65-72 1071 Transient musical hallucinosis of central origin: a review and clinical study Table 1 Reviewed cases of spontaneous musical or verbal AHs, or both, of central origin, whether or not associated with peripheral pathology, with exclusion of psychiatric and alcoholic aetiologies Number of relevant cases (n = 118) Author(s) Aizenber et a"'6 Bergman 6 case 1 1 12 1 1 4 4 11 Berrios" Berthier and Starkstein"' Boza and URett'4 Cambier et al Courville' Recorded cases case 1 cases 1,2,3,4 cases 4663, 15863, 19244, 20125, 22359, 43, 582, 22383, 18273, 15440, 22539 1 2 2 7 1 Cummings et al" David et al7 De Ajuriaguerra et alt De Morsier"' De Reuck et at 4' Dyck'2 Fenton and McRae"" Hammeke et al" Hecaen and Ropert4' 1 2 19 Keschner etal9 Keshavan et at 7" 4 1 Lennox"2 1 Mikati et at4' Miller and Crosbr"' Moniz and Loff6 Mulder and Daly77 1 1 1 1 1 1 5 1 21 Neppe4' cases 11,12 cases 25,26, 28,29,30,31,32 case 1 1 " Neumann et al Paillas and Subirana'7 Patterson4 ' Penfield and Perot49 cases 1, 2, 3, 4, 7, 8, 9, 10, 14, 15, 16, 20, 21, 23, 24, 27, 28, 30, 32 case 1 cases 6, 7, 10, 12, 16, 24, 29, 41, 42, 43, 44, 45, 46, 47, 58, 59, 60, 62, 63, 64, 65 case 9 1 1 1 1 1 1 6 Robertson'9 Riese"' Saijo et al" Scott" Shapiro et alt" Tanabe et alt Tarachow"1 * In addition, Penfield and Perot49 reported 26 cases in which they observed complex auditory phenomena following cortical stimulation. Elementary and complex AHs may also occur with lesions of the tegmentum of the pons and lower midbrain.56 MRI, CT and BAEP, however, failed to disclose a brainstem lesion in our patient, indicating that it was not brainstem auditory hallucinosis. Tanabe et al'5 described a patient who developed a transient verbal hallucinosis in the right ear, which lasted for 17 days, as well as fluent aphasia following a left temporal haemorrhagic infarction. CT scans obtained during admission disclosed a low density area with small, high density spots in the left superior temporal gyrus, which was partially enhanced by contrast medium. However, when the hallucinosis had disappeared, the area with abnormal attenuation values was Table 2 Selected cases of complex AHs of central origin (Letters refer to authors' initials, followed by their patient's case number) Spontaneous lesion Type of perceptions Right Musical, songs Left Right PP46 HR15 PP5, PP9 PP17 PP30 PP3, PP7 PP8, PP1 5 PP16, PP28 Dl Verbal, voices PP29 Experimental stimulus PP43 PP44 DM25 Left PP11 PP31 PP12 HR10 Verbal and musical PP7 HR16 ML PP45 T PP13 PP14 D = David et at 75; DM = De Morsier6'; HR = Hecaen and Ropert42; ML = Moniz and Loff "; PP = Penfield and Perot49; T = Tanabe et alt". no longer found. A linear, low density area remained at the lateral edge of the left superior temporal gyrus, and enlargement of the left sylvian fissure was noticed. The concomitant disappearance of both the hyperdensities on the CT scans and the auditory phenomena might suggest that the second of these was caused by the abnormal excitatory effect of the haemorrhagic component of the lesion. According to Berrios,57 musical perceptions tend to disappear together with the underlying pathology when associated with strokes. Such an abnormal brain excitability may well have brought forth the unilateral musical perceptions in our patient as well, as there seems to be a parallelism between the course of the phenomena experienced in the left ear and the progressive disappearance on CT of the hyperdense aspect of the right sylvian fissure. Moreover, the lesion location in our patient, as shown by CT and MRI, is consistent with the one described in those patients with unilateral complex AHs that Tanabe et al15 recorded in the literature on unilateral AHs of central origin: the lesions were located around the sylvian fissure and centred on the first temporal convolutions. In the cases reviewed by Tanabe et al 1 as in our patient, the auditory phenomena were lateralised in the opposite ear to the involved hemisphere. Further evidence of this lateralisation phenomenon in AHs of central origin can be found in Penfield and Perot.49 For instance, they induced a voice lateralised in the left ear by stimulating the right temporal cortex of their patient (case 29), and reported a patient (case 45) with left temporal lobe pathology who experienced verbal and musical phenomena in the right hemispace. The crucial question is whether verbal hallucinosis is associated with left hemisphere, and musical hallucinosis with right hemisphere lesions in right handed individuals. Berrios57 expressed the view that the non-dominant hemisphere plays an important role in the generation of musical phenomena in patients with brain lesions, and that this finding fits in well with what is known about music processing in the brain. He also claims that there might be a dissociation between musical perceptions and the putative mechanisms related to hallucinatory voices in schizophrenic subjects, which seem to be associated with the dominant hemisphere.73 To evaluate this view, we reviewed 118 patients with spontaneous musical or verbal AHs or both (table 1). Only those cases with sufficient data on the contents of the hallucinations and the site of lesion were chosen as subjects of investigation. We excluded cases with concomitant convulsive speech acts, concomitant hallucinations in modalities other than the auditory one, concomitant mental disorders, past history of alcohol overconsumption and of mental illness, deafness and ear disease, evidence of bilateral cerebral involvement, insufficient information on handedness, cerebral dominance, or clinical picture. Table 2 gives an overview of the remaining 28 selected cases, according to the type of auditory perceptions, lateralisation 1072 Paquier, van Vugt, Bal, Cras, Parizel, van Haesendonck, Creten, Martin (right versus left hemisphere) and nature (spontaneous versus experimental condition) of the lesion. No significant differences were found either between left versus right lateralisation of lesion/stimulus and type of auditory phenomena (G = 1 37 < x2 = 5.99, p = 0.05) or between the nature of lesion/stimulus and type of auditory phenomena (G = 1-81 < X = 5 99, p = 005). Our analysis indicates that there is no close association between the kind of phenomena experienced (verbal versus musical) and laterality of the lesion, and consequently does not enable us to confirm Berrios'57 conclusions. It supports Hecaen and Albert's80 findings that both complex musical and verbal hallucinosis with a clear, external sensory quality can be produced by lesions confined to the same hemisphere. In conclusion, we reviewed the different clinical conditions that may cause AHs, and compared them with the clinical picture of the patient we described. We retained two major hypotheses to explain the occurrence of her auditory phenomena. Although the clinical evidence favours a neurological aetiology, the occurrence of a concomitant ear disease does not enable us to ignore the possible contribu- tory and precipitating role of the otological factor. Whether the combination of the central and peripheral dysfunction was the necessary condition to cause the patient's musical perceptions remains uncertain. Nevertheless, both the description of our patient and the review of reported cases support the view that, in patients with organic cerebral disease, unilateral AHs can be considered a significant clinical sign indicating a lesion in the contralateral hemisphere. But we were not able to confirm the hypothesis that, in cases of hemispheric lesion, musical perceptions are related to pathology of the right hemisphere only. 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