Abstract:
Auditory hallucinations (AH) are conscious perception of sound in the form of meaningful environmental sound, voice or music in the absence of external stimulus. AHs have been linked to schizophrenia and other psychotic disorders for a long time. Recent evidence suggests that AHs are common in non-psychotic people and are sometimes linked to hearing loss. Estimating the prevalence of AHs in the hearing impaired population and assessing their impact are both necessary. The role of an audiologist will be required to investigate this area, identify the pathophysiological mechanism, and develop effective intervention strategies based on the estimated prevalence rates and their impact.
Aim: This study aims to estimate the prevalence of AH’s and their impact on hearing impaired individuals. The objectives include; estimating prevalence of AH’s across age ranges, identifying the type and content of hallucinations, assess a relationship between severity of hearing loss and AH’s, estimate an association between configuration of hearing loss and AH’s, and finally compare quality of life outcomes between hallucinating and non-hallucinating individuals.
Method: Spontaneous Acoustic Phenomena was used to identify presence and content of hallucinations in 500 individuals age ranging between 18-65 years reported to AIISH in 2019. WHOQOL-BREF, a quality of life measure was administered on 30 hallucinating individuals and the scores were compared to 30 age, gender and diagnosis matched non-hallucinating individuals.
Results: The overall prevalence of hallucinations was 8.8%, with higher prevalence in hearing impaired and individuals between the age range of 31-50 years (11.04%). Majority of individuals experienced meaningful environmental sounds and 16% and 11% of hallucinating individuals experienced voice and music, respectively. No correlation was established between severity and AH’s. A significant association between configuration of hearing loss and AH’s was found. No significant difference was found between hallucinating and non-hallucinating hearing impaired individuals. Hallucinating normal hearing individuals scored significantly lower than non-hallucinating counterparts.
Conclusion: Higher prevalence in hearing impaired participants indicates the role of auditory pathways in the occurrence of AH’s. Hallucinations adversely impact the quality of life of hallucinating individuals. This necessitates the involvement of an audiologist in the assessment, intervention and future scientific studies on AH’s.