Perceptual adaptation is an active cognitive process where listeners re-analyse speech categories based on new contexts/situations/talkers. It involves top-down influences from higher cortical levels on lower-level auditory processes. Individuals with congenital amusia have impaired pitch processing with reduced connectivity between frontal and temporal regions. This study examined whether deficits in amusia would lead to impaired perceptual adaptation in lexical tone perception. Thirteen Mandarin-speaking amusics and 13 controls identified the category of target tones on an 8-step continuum ranging from rising to high-level, either in isolation or in a high-/low-pitched context. For tones with no context, amusics exhibited reduced categorical perception than controls. While controls’ lexical tone categorization demonstrated a significant context effect due to perceptual adaptation, amusics showed similar categorization patterns across both contexts. These findings suggest that congenital amusia impacts the extraction of context-dependent tonal categories in speech perception, indicating that perceptual adaptation may depend on listeners’ perceptual acuity.

知觉适应是一个主动的认知过程，听众根据新的上下文/情况/谈话者重新分析语音类别。它涉及来自较高皮质层对较低层听觉过程的自上而下的影响。先天性失忆症患者的音高处理受损，额叶和颞区之间的连通性降低。这项研究检查了失忆症的缺陷是否会导致词汇音调感知的感知适应受损。13 个说普通话的 amusics 和 13 个控件在从上升到高电平的 8 步连续体中确定了目标音的类别，无论是在孤立的还是在高/低音的上下文中。对于没有上下文的音调，乐音表现出比对照降低的分类感知。虽然控件的词汇音调分类由于知觉适应而表现出显着的上下文效应，但 amusics 在两种上下文中显示出相似的分类模式。这些发现表明先天性失忆会影响语音感知中上下文相关音调类别的提取，表明感知适应可能取决于听者的感知敏锐度。