Hagedorn Christina, Proctor Michael, Goldstein Louis, Wilson Stephen M, Miller Bruce, Gorno-Tempini Maria Luisa, Narayanan Shrikanth S
University of Southern California, Los Angeles.
Macquarie University, North Ryde, New South Wales, Australia.
J Speech Lang Hear Res. 2017 Apr 14;60(4):877-891. doi: 10.1044/2016_JSLHR-S-15-0112.
Real-time magnetic resonance imaging (MRI) and accompanying analytical methods are shown to capture and quantify salient aspects of apraxic speech, substantiating and expanding upon evidence provided by clinical observation and acoustic and kinematic data. Analysis of apraxic speech errors within a dynamic systems framework is provided and the nature of pathomechanisms of apraxic speech discussed.
One adult male speaker with apraxia of speech was imaged using real-time MRI while producing spontaneous speech, repeated naming tasks, and self-paced repetition of word pairs designed to elicit speech errors. Articulatory data were analyzed, and speech errors were detected using time series reflecting articulatory activity in regions of interest.
Real-time MRI captured two types of apraxic gestural intrusion errors in a word pair repetition task. Gestural intrusion errors in nonrepetitive speech, multiple silent initiation gestures at the onset of speech, and covert (unphonated) articulation of entire monosyllabic words were also captured.
Real-time MRI and accompanying analytical methods capture and quantify many features of apraxic speech that have been previously observed using other modalities while offering high spatial resolution. This patient's apraxia of speech affected the ability to select only the appropriate vocal tract gestures for a target utterance, suppressing others, and to coordinate them in time.
实时磁共振成像（MRI）及相关分析方法被证明能够捕捉并量化失用性言语的显著特征，证实并扩展了临床观察以及声学和运动学数据所提供的证据。本文提供了在动态系统框架内对失用性言语错误的分析，并讨论了失用性言语的病理机制性质。
一名患有言语失用症的成年男性说话者在进行自发言语、重复命名任务以及为引发言语错误而设计的单词对自定节奏重复时，接受了实时MRI成像。分析了发音数据，并使用反映感兴趣区域发音活动的时间序列检测言语错误。
实时MRI在单词对重复任务中捕捉到了两种类型的失用性手势侵入错误。还捕捉到了非重复性言语中的手势侵入错误、言语开始时的多个无声起始手势以及整个单音节词的隐蔽（未发声）发音。
实时MRI及相关分析方法能够捕捉并量化许多以前使用其他方式观察到的失用性言语特征，同时提供高空间分辨率。该患者的言语失用影响了为目标话语仅选择适当的声道手势、抑制其他手势以及及时协调这些手势的能力。
