Aim. An overview of current knowledge on unreal musical perceptions is followed by an analysis of 75 cases of this disorder reported (except for one case) in the literature. Unreal musical perceptions, usually called hallucinations, according to the literature more frequent in females and in the elderly, are associated with hearing impairment and brain dysfunction, especially of the non-dominant hemisphere. Prognosis is considered to be uncertain.
Sample and methods. In the analysis of 75 cases of musical hallucinations and parahallucinations reported in mostly the English-language publications in the years 1975-2002, the nature of these patients' mental disorders and organic changes, characteristics and type of their musical perceptions, as well as treatment methods and their efficacy were taken into account.
Results. Five groups of unreal musical perceptions can be distinguished: these related to mental disorders (depression especially), to diseases of the central nervous system, idiopathic, drug-induced, or associated with a severe somatic illness. In all the analysed groups females and individuals with some hearing impairment predominated. A third of the patients were aged under 60 years. Brain lesions were situated in both hemispheres and. in the brain stem. Good results of treatment were attained in 75% of female and almost 90% of male patients.
Conclusions. Only in same cases musical perceptions could be recognised as hallucinations due to the patient's lack of insight into their unreal nature. In a majority of cases the presence of insight indicated that such perceptions were parahallucinations (hallucinoids), or sensory automatisms.