Cogn Neuropsychol. 2001 Jul 1;18(5):411-37. doi: 10.1080/02643290125702.
This study describes an amateur musician, KB, who became amusic following a right-hemisphere stroke. A series of assessments conducted post-stroke revealed that KB functioned in the normal range for most verbal skills. However, compared with controls matched in age and music training, KB showed severe loss of pitch and rhythmic processing abilities. His ability to recognise and identify familiar instrumental melodies was also lost. Despite these deficits, KB performed remarkably well when asked to recognise and identify familiar song melodies presented without accompanying lyrics. This dissociation between the ability to recognise/identify song vs. instrumental melodies was replicated across different sets of musical materials, including newly learned melodies. Analyses of the acoustical and musical features of song and instrumental melodies discounted an explanation of the dissociation based on these features alone. Rather, the results suggest a functional dissociation resulting from a focal brain lesion. We propose that, in the case of song melodies, there remains sufficient activation in KB's melody analysis system to coactivate an intact representation of both associative information and the lyrics in the speech lexicon, making recognition and identification possible. In the case of instrumental melodies, no such associative processes exist; thus recognition and identification do not occur.
本研究描述了一位业余音乐家 KB，他在右脑中风后成为了一位失歌症患者。中风后的一系列评估显示，KB 在大多数语言技能方面表现正常。然而，与年龄和音乐训练相匹配的对照组相比，KB 表现出严重的音高和节奏处理能力丧失。他识别和辨认熟悉的器乐旋律的能力也丧失了。尽管存在这些缺陷，但当被要求识别和辨认没有伴随歌词的熟悉歌曲旋律时，KB 的表现非常出色。这种在识别/辨认歌曲和器乐旋律之间的分离在不同的音乐材料集中得到了复制，包括新学习的旋律。对歌曲和器乐旋律的声学和音乐特征的分析排除了仅基于这些特征的解释。相反，结果表明这种分离是由于局灶性脑损伤导致的功能分离。我们提出，在歌曲旋律的情况下，KB 的旋律分析系统中仍然存在足够的激活，以共同激活与歌词相关的信息和语音词汇中完整的表示，从而使识别和辨认成为可能。在器乐旋律的情况下，不存在这种联想过程，因此不会进行识别和辨认。
