Martin Kelly C, DeMarco Andrew T, Dyslin Sara M, Turkeltaub Peter E
Georgetown University Medical Center, Department of Neurology, Washington, DC, USA.
Georgetown University Medical Center, Department of Neurology, Washington, DC, USA; MedStar National Rehabilitation Hospital, Washington, DC, USA.
Cortex. 2025 Jul 25;191:12-24. doi: 10.1016/j.cortex.2025.03.014.
After initial bilateral acoustic processing of the speech signal, much of the subsequent language processing is left-lateralized, perhaps due to a left hemisphere (LH) advantage for rapidly unfolding components of speech. Here we investigated whether and where damage to the LH predicted impaired performance on judging the directionality of frequency modulated (FM) sweep stimuli that changed within short (25 msec) or longer (250 msec) temporal windows. Performance was significantly lower for stroke survivors (n = 50; 18 female) than controls (n = 61; 34 female) on FM Sweeps judgments, particularly on the short sweeps. Support vector regression lesion-symptom mapping revealed that part of the left planum temporale (PT) was related to worse performance on the short FM sweeps, controlling for performance on the long sweeps. We then investigated whether damage to this region related to diminished performance on stop consonant identification and pseudoword repetition, which theoretically depend on rapid auditory processing. Indeed, participants with PT lesions (PT lesion+, n = 24) performed worse than those without (PT lesion-, n = 26) on stop consonant identification and pseudoword repetition, controlling for lesion size and hearing ability. PT lesions impacted pseudoword repetition more than real word repetition, which is of interest because pseudowords rely solely on speech sound perception and sequencing, whereas words can also rely on lexical-semantic knowledge. We conclude that the left PT is a critical region for processing auditory information in short temporal windows, and it may also be an essential transfer point in auditory-to-linguistic processing.
在对语音信号进行初始双侧声学处理之后，后续的大部分语言处理都偏向左侧化，这可能是由于左半球（LH）在快速展开的语音成分方面具有优势。在此，我们研究了LH损伤是否以及在何处预示着在判断短（25毫秒）或长（250毫秒）时间窗口内变化的调频（FM）扫描刺激的方向性时表现受损。中风幸存者（n = 50；18名女性）在FM扫描判断上的表现显著低于对照组（n = 61；34名女性），尤其是在短扫描上。支持向量回归损伤-症状映射显示，左颞平面（PT）的一部分与短FM扫描时较差的表现相关，同时控制长扫描时的表现。然后，我们研究了该区域的损伤是否与塞音识别和假词重复表现的下降有关，从理论上讲，这取决于快速听觉处理。确实，患有PT病变的参与者（PT病变 +，n = 24）在塞音识别和假词重复上的表现比没有PT病变的参与者（PT病变 -，n = 26）差，同时控制病变大小和听力能力。PT病变对假词重复的影响大于对真词重复的影响，这很有意思，因为假词仅依赖于语音感知和序列，而单词还可以依赖词汇语义知识。我们得出结论，左PT是在短时间窗口内处理听觉信息的关键区域，并且它也可能是听觉到语言处理中的一个重要转换点。
