Researchers Find New Ways for Pediatric CI Users’ Auditory Rehabilitation Evaluation

The Neural Engineering Team of Tianjin University, together with the Audiology Team of Beijing Children’s Hospital, Capital Medical University National Center for Children’s Health, proposed an objective electroencephalography-based assessment means for auditory rehabilitation of pediatric cochlear implant users, and published their research findings in the journal Hearing Research. By designing an experimental paradigm suitable for young children, this research laid a foundation for applying Brain-Computer Interface to children's auditory rehabilitation, and made it possible to provide a more accurate reference for adjusting cochlear implant processors and auditory speech rehabilitation training.

Over the last two decades, Cochlear Implant (CI) technology has been rapidly developed and widely used in clinical practice. It has become one of the most successful neuro-engineering achievements. CI provides an effective rehabilitation way for hearing-impaired children by promoting sound perception, vocalization, and language ability. However, existing clinical assessment approaches, including questionnaires and behavioral assessments, are susceptible to many factors and have significant subjective limitations, especially for younger prelingually deaf children. There is an urgent need for developing more scientific and effective testing and assessment means to help understand the intrinsic hearing mechanism, assess the hearing rehabilitation process objectively, and provide a more accurate reference for CI adjusting and auditory rehabilitation training.

"Healthy China Action (2019-2030)" explicitly points out that special cares should be paid to the health of children, senior citizens, people with disabilities, and other vulnerable groups. According to a survey conducted by the National Health Commission of the People’s Republic of China, about 115,000 children under 7 years old suffer from profound or complete hearing loss in China, and about 30,000 newborns have hearing impairment every year. In fact, China has the largest number of pediatric CI users in the world. However, as CI is unable to capture the full extent of tonal varieties, it is challenging for Chinese CI users who speak a tone language to recognize intonation changes.

In order to evaluate pediatric CI users’ hearing rehabilitation effectiveness and recognition ability, the research team designed an experimental paradigm varying in pure-tone, syllable, and tonal sounds for young children. Researchers utilized cortical auditory evoked potential (CAEP) and mismatch negativity (MMN) to obtain time-domain analysis, and investigated the source localization to obtain spatial accuracy of the auditory cortex's plasticity.

The research found that the auditory system experienced a critical period of rapid development in 3-6 months after implantation. In terms of language learning, 6-12 months after implementation is the key to intonation recognition. The experiments on 91 children aged three to seven (66 patients, 25 normal children) show that CAEP is more suitable for assessing early auditory system reconstruction, while MMN performs better in evaluating advanced auditory functions, such as auditory recognition ability. Furthermore, source localization has been proven to be an efficient tool in exploring auditory cortex plasticity, which can provide additional information for auditory rehabilitation evaluation, especially for pediatric CI users.

The research findings were published in the journal Hearing Research, entitled “Objective electroencephalography-based assessment for auditory rehabilitation of pediatric cochlear implant users”. This journal is one of the most authoritative and influential professional academic journals in hearing science. The research team will further conduct long-term rehabilitation assessments and large-scale clinical applications based on existing achievements.

The first author of this paper is NI Guangjian, a professor of the Neural Engineering Team of Tianjin University, and ZHENG Qi, a doctoral student. The corresponding author is Professor MING Dong of Tianjin University, and Professor LIU Haihong of Beijing Children’s Hospital, Capital Medical University National Center for Children’s Health.

By Wu Mengqi

Editor: Eva Yin