Tonal Perception Ability of Thai Children with Cochlear Implants and Hearing Aids

Background: Thai is one of several tonal languages. Accordingly, words spoken with different tones will change their meaning. Sensorineural hearing loss children have difficulty in perceiving tones which is directly related to a low level of speech understanding and intelligibility.Objectives: This study compared the tonal perception ability of severe-to-profound hearing loss children and profound hearing loss children who used hearing aids and cochlear implants respectively.Material and methods: Sixteen pre-lingual sensorineural hearing loss children from a preschoolaural rehabilitation program at Ramathibodi Hospital, Mahidol University, were selected. Subjects consisted of 8 bilateral hearing aid children and 8 unilateral cochlear implant children who were trained in the program for more than 3 years and able to produce speech recognition scores. All subjects demonstrated reasonable aided responses with their hearing devices. A Thai tone identification and discrimination test was used in this study. These tests were conducted by an experienced audiologist in a quiet room. The scores of the hearing aid group and the cochlear implant group were compared.Results: There were significant differences in tonal identification scores and tonal discrimination scores for the cochlear implant group when compared to the hearing aid group (p<0.05)Conclusion: Cochlear implantation provided better tonal perception of Thai lexical tone identification and discrimination of profound hearing loss children than severe-to-profound hearing loss children who used bilateral hearing aids.