Study of the neural plasticity in adults and older adults new hearing aid users

ABSTRACT Purpose: to monitor, with long-latency auditory evoked potentials, the plasticity of the central auditory pathways in adults and older adults, new users of hearing aids. Methods: a total of 15 adults and older adults, aged 55 to 85 years, participated in the research. They had a symmetric bilateral mild to moderate sensorineural hearing loss, without previous experience with any type of hearing aid. The long-latency auditory evoked potentials were conducted with and without amplification, at 60 and 75 dBnHL, with speech stimulus in a sound field, in two assessment moments: up to one week after fitting the hearing aid and after six months of its use. The Student’s t-test was used for statistical analysis, considering significant the p-value < 0.05. Results: responses with lower latency values were observed for the right ear in the second assessment. Comparing the first with the second assessment, both with and without the hearing aid, an increase in the amplitude of P2-N2 was observed, as well as an increase in the latency of the P2 component at the intensity of 75 dBnHL. No statistically significant differences were observed at the intensity of 60 dBnHL. Conclusion:the use of the hearing aid promoted the plasticity of the central auditory pathways, increasing the number of neurons responsive to the sound stimuli.

摘要
研究目的：本研究旨在通过长潜伏期听觉诱发电位（long-latency auditory evoked potentials），监测成人及老年助听器新使用者的中枢听觉通路可塑性。
研究方法：共纳入15名年龄介于55至85岁的成人与老年受试者，其均存在对称性双侧轻中度感音神经性听力损失，且无任何类型助听器使用史。实验设置两个评估时间点：佩戴助听器后1周内，以及使用助听器6个月后；分别在有放大（佩戴助听器）与无放大（未佩戴助听器）条件下，于声场中以语音刺激、60 dBnHL和75 dBnHL强度记录长潜伏期听觉诱发电位。统计学分析采用t检验（Student’s t-test），以p值<0.05作为差异具有统计学意义的判定标准。
研究结果：第二次评估时，受试者右侧耳的诱发电位潜伏期更短。对比两次评估结果，无论是否佩戴助听器，在75 dBnHL强度下，P2-N2波幅均显著升高，且P2成分的潜伏期延长；而在60 dBnHL强度下未观察到统计学显著差异。
研究结论：助听器的使用可促进中枢听觉通路可塑性，增加对声音刺激产生响应的神经元数量。