ABSTRACT

Studies of non-native speech sound learning report considerable individual variability in learning new sounds and retaining them in memory. The current study tested whether individual variation in brain structure (measured using MRI) accounts for differences in learning or retention of non-native speech sounds. Fifty-seven participants were tested on identification and discrimination of difficult non-native speech sounds in the evening before training, after training, and tested again the next morning. Surface area and volume of the left superior temporal gyrus positively predicted discrimination learning, whereas surface area of the left transverse temporal gyrus negatively predicted overnight improvement of identification. Hippocampal volume as well as gyrification of bilateral transverse temporal gyri positively predicted overnight improvement of discrimination. Findings suggest that individual differences in non-native speech sound learning can be traced to differences in brain structure supporting perception, while differences in retention are linked to the structure of hippocampal regions important for memory consolidation.

摘要

非母语语音学习的研究报告了在学习新声音并将其保留在记忆中的相当大的个体差异。当前的研究测试了大脑结构的个体差异（使用 MRI 测量）是否会导致学习或保留非母语语音的差异。57 名参与者在训练前一晚、训练后接受了对困难的非母语语音识别和辨别的测试，并在第二天早上再次测试。左侧颞上回的表面积和体积正预测识别学习，而左侧颞横回的表面积负预测识别的隔夜改进。海马体积以及双侧颞叶横回的旋转积极预测隔夜识别能力的改善。研究结果表明，非母语语音学习的个体差异可以追溯到支持感知的大脑结构的差异，而保留的差异与对记忆巩固很重要的海马区域的结构有关。