PHYSIOLOGICAL DEVELOPMENT OF SPEECH PRODUCTION

言语产生的生理发展 尽管我们对理解的重要性， 发育性言语障碍和正常言语运动模型 控制 在理论模型和临床应用中， 协调，像其他复杂的运动行为一样，被认为是 源自节律性的、稳态的、中枢模式化的功能， 呼吸、咀嚼和吸吮。 这一假设尚未得到验证， 尽管它直观的吸引力，可能会被怀疑，因为 证明了中央模式行为和言语之间的差异 成年人的生产（摩尔，史密斯和林格尔，1988年）。 实证 这一假设的评估对正常模型和 语言运动控制和诊断的基本原理， 治疗儿童发育性语言障碍。 建议对发育正常的儿童进行调查， 协调中枢模式的口腔和呼吸行为 言语协调。 这种对比将提供一个定量的 在良好理解的运动背景下描述言语发展 行为。 小学生言语运动控制的生理发展 幼儿（9-48个月）的语音子系统将 使用横截面（70名儿童）和纵向（20名儿童）进行描述 儿童）设计。 呼吸驱动系统的协调， 下颌运动、发声和发音将被量化 在讲话期间和在自动的、有节奏的、非讲话行为期间， 咀嚼和休息呼吸。 肌电图（EMG）、声学和 将分析运动学信号。 发音协调和 喉部控制将从共振峰（F1和F2）轨迹推断 和基频（f-o）轮廓。 肌肉相对计时 将使用E G信号的相关分析来量化活动。 由成对的语音肌肉产生的信号相干性将在 以检测来自共同神经源的活动。 非零 成对EMG信号内的相干性已经被证明是可观察的 具有节律性运动行为的特征，包括咀嚼和 呼吸，两者都是由中央模式发生器介导的 （CPG）在许多物种中。 在时间上的发展变化， EMG信号的频谱特征将描述 自动的，非言语协调组织在言语成熟。

The physiological development of speech production has remained largely unexplored in spite of Us importance to understanding developmental speech disorders and to models of normal speech motor control. In theoretical models and clinical applications, speech coordination, like other complex motor behaviors, has been assumed to be derived from rhythmic, homeostatic, centrally patterned functions such as respiration, chewing, and sucking. This assumption has not been tested, and despite its intuitive appeal, might be doubted because of demonstrated differences between centrally patterned behaviors and speech production in adults (Moore, Smith, & Ringel, 1988). An empirical evaluation of this assumption has implications both for models of normal speech motor control and for the rationale underlying diagnosis and treatment of children with developmental speech disorders. The proposed Investigation of normally developing children contrasts the coordination of centrally patterned oral and respiratory behaviors with speech coordination. This contrast will provide a quantitative description of speech development in the context of well-understood motor behaviors. Physiological development of speech motor control in primary speech subsystems in young children (9-48 months of age) will be described using a cross-sectional (70 children) and longitudinal (20 children) design. Coordination of systems for respiratory drive, mandibular movement, phonation, and articulation will be quantified during speech and during automatic, rhythmic, non-speech behaviors such as chewing and resting breathing. Electromyographic (EMG), acoustic, and kinematic signals will be analyzed. Articulatory coordination and laryngeal control will be inferred from formant (F1 and F2) trajectories and fundamental frequency (f-o) contours. Relative timing of muscle activity will be quantified using correlational analysis of E G signals. Signal coherence arising from paired speech muscles will be computed in order to detect activity arising from a common neural source. Non-zero coherence within paired EMG signals has been shown to be an observable characteristic of rhythmic motor behaviors, including mastication and respiration, both of which are mediated by central pattern generators (CPGs) in many species. Developmental changes in the temporal and spectral characteristics of EMG signals will delineate the role of automatic, non-speech coordinative organization in speech maturation.