Langerak Nienke Cornelia, Stronks Hendrik Christiaan, Briaire Jeroen Johannes, Frijns Johan Hubertus Maria
Department of Otorhinolaryngology and Head & Neck Surgery, Leiden University Medical Center, Leiden, The Netherlands.
Leiden Institute for Brain and Cognition, Leiden University, Leiden, The Netherlands.
Audiol Neurootol. 2025 Aug 25:1-11. doi: 10.1159/000547205.
Cochlear implantation (CI) is the standard treatment for severe-to-profound sensorineural hearing loss, but CI users often struggle with speech understanding in noisy environments. The Dutch/Flemish Matrix test is frequently used to evaluate speech-in-noise performance due to its assumed immunity to learning effects. However, studies challenge this assumption, revealing significant learning effects that can confound research outcomes. In this study, we modeled the learning curves of the Dutch/Flemish Matrix test to assess the influence of both between-session and between-test effects. We hypothesized that a exponential model would describe the learning effects more accurately than a linear model.
The perceptual learning effects associated with the Dutch/Flemish Matrix test were assessed in 17 bimodal CI users. All participants performed the Matrix speech-in-noise tests across four sessions, with 13 randomized tests per session. The tests were conducted in a soundproof booth with an eight-speaker babble noise. The outcome parameter was the speech recognition threshold and was analyzed with a linear mixed model to account for confounders.
The results showed a statistically significant learning effect between sessions that added up to a speech intelligibility increase of 1.3 dB signal-to-noise ratio (SNR) (equivalent to ∼10% word score) between the first and second sessions, 0.86 dB SNR (∼7%) between the second and third sessions and 0.67 dB SNR (∼5%) between the third and fourth sessions. In addition, a statistically significant within-session learning effect (i.e., between tests) was observed with a linear slope of -0.11 dB SNR/test (∼0.9% word score/test), which accumulates to a total of 1.7 dB SNR (13%) between session start and end. The between-session learning curve was described more accurately with an exponential fit than with a linear fit. The between-test learning curve can be described equally well with a linear and an exponential fit.
A robust between-test learning effect was observed, which could be accurately modeled using either a linear or exponential learning curve. Additionally, a between-session learning effect was evident and was best described by an exponential learning curve. This study provides an important handle for correcting these learning effects in future studies.
人工耳蜗植入（CI）是重度至极重度感音神经性听力损失的标准治疗方法，但CI使用者在嘈杂环境中的言语理解能力往往较差。荷兰/弗拉芒语矩阵测试因其假定不受学习效应影响，常被用于评估噪声环境下的言语表现。然而，研究对这一假设提出了质疑，揭示出显著的学习效应可能会混淆研究结果。在本研究中，我们对荷兰/弗拉芒语矩阵测试的学习曲线进行建模，以评估不同测试阶段之间以及不同测试之间的效应影响。我们假设指数模型比线性模型能更准确地描述学习效应。
对17名双模式CI使用者评估与荷兰/弗拉芒语矩阵测试相关的感知学习效应。所有参与者在四个测试阶段进行矩阵噪声环境下的言语测试，每个阶段有13次随机测试。测试在配备八个扬声器的隔音室中进行，背景为嘈杂噪声。结果参数为言语识别阈值，并采用线性混合模型进行分析以控制混杂因素。
结果显示，不同测试阶段之间存在统计学显著的学习效应，在第一和第二阶段之间，言语清晰度提高了1.3 dB信噪比（SNR）（相当于单词得分提高约10%），第二和第三阶段之间提高了0.86 dB SNR（约7%），第三和第四阶段之间提高了0.67 dB SNR（约5%）。此外，观察到测试阶段内存在统计学显著的学习效应（即不同测试之间），线性斜率为-0.11 dB SNR/测试（约0.9%单词得分/测试），从测试阶段开始到结束累计提高了1.7 dB SNR（13%）。不同测试阶段之间的学习曲线用指数拟合比线性拟合更准确。不同测试之间的学习曲线用线性拟合和指数拟合效果相当。
观察到了显著的不同测试之间的学习效应，使用线性或指数学习曲线均可对其进行准确建模。此外，不同测试阶段之间的学习效应明显，用指数学习曲线描述最佳。本研究为未来研究中校正这些学习效应提供了重要依据。
