Implicit and explicit motor learning in children and adults who stutter

口吃儿童和成人的内隐和外显运动学习

• 批准号: RGPIN-2015-05869
• 负责人: DeNil, Luc
• 金额: $ 1.75万
• 依托单位: University of Toronto
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2016
• 资助国家: 加拿大
• 起止时间: 2016-01-01 至 2017-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=613795
• 关键词: Implicit; explicit; motor; learning; children

Developmental stuttering is a speech fluency disorder, which typically has its onset in pre-pubescent children. There is significant evidence that speech motor deficits are at the core of the disorder. These deficits, which likely are genetic and neural in nature, are considered fundamental to our understanding of the onset, development and recovery from stuttering. In our previous research, we have investigated the extent to which adults who stutter are deficient in their ability to acquire novel motor skills. Our results have demonstrated that these adults are less proficient than nonstuttering speakers acquiring new speech sequences, even after extensive practice. Early evidence of differences in skill consolidation between the stuttering and nonstuttering adults has suggested that this deficit may reflect both motor execution and motor learning processes. Importantly, our results also have shown clear parallels between deficient performance in both speech and non-speech (finger sequencing) motor skills, supporting the hypothesis that these deficiencies affecting people who stutter are not limited to speech articulation but may reflect a general motor deficit.  Learning a motor skill is a procedural learning process during which performance improves gradually over many repetitions of the task. This process can be both explicit and implicit. Implicit motor learning refers to learning that is incidental, and in which participants are not aware of what they have learned and of how they perform the task. Explicit motor learning can be intentional, and participants are conscious of their knowledge and can report it. These two learning strategies are suggested to reflect different learning mechanisms that rely on distinct neural substrates. We have hypothesized that both implicit and explicit learning may be involved in the development of stuttering but the relative weight of these two processes has not been investigated. Implicit motor learning clearly is important during the early development of speech and it has been suggested that people who stutter may rely to a larger extent on explicit strategies. In addition, both implicit and explicit learning may be affected by the presence of an unstable sensorimotor speech system. Importantly, it has been proposed that explicit learning relies on the establishment of stable internal motor models. The failure to do so for speech may lead to disrupted speech fluency. Unraveling the unique contributions of implicit and explicit motor learning in the development of stuttering is critical to understanding this speech fluency disorder. The proposed project outlines studies aimed at investigating motor learning skills in children and adults who stutter. The project will contribute significantly to our understanding of the nature and development of stuttering and will inform the ongoing refinement of motor control models for speech.

发育性口吃是一种语言流畅性障碍，通常始于青春期前的儿童。有重要证据表明，言语运动障碍是这种疾病的核心。这些缺陷很可能是遗传的和神经的，被认为是我们理解口吃的发生、发展和恢复的基础。在我们之前的研究中，我们调查了口吃的成年人在获得新的运动技能方面的能力不足的程度。我们的结果表明，即使经过广泛的练习，这些成年人获得新的语音序列的能力也不如非口吃的人。早期证据表明，口吃成年人和非口吃成年人在技能巩固方面的差异表明，这种缺陷可能反映了运动执行和运动学习过程。重要的是，我们的研究结果还显示，在语音和非语音(手指测序)运动技能方面表现不佳之间存在明显的相似之处，这支持了一种假设，即这些影响口吃者的缺陷不仅限于语音清晰度，还可能反映出一般的运动障碍。 学习运动技能是一个程序性的学习过程，在这个过程中，表现会随着任务的多次重复而逐渐提高。这一过程可以是显性的，也可以是隐性的。内隐运动学习是指参与者不知道他们学到了什么，也不知道他们是如何完成任务的附带学习。外显的运动学习可能是有意的，参与者意识到他们的知识，并可以报告。这两种学习策略是为了反映依赖于不同神经基础的不同学习机制。我们假设内隐学习和外显学习都可能参与口吃的发展，但这两个过程的相对权重尚未得到研究。内隐运动学习显然在言语发展的早期阶段很重要，有研究表明，口吃者可能在更大程度上依赖于外显策略。此外，内隐和外显学习都可能受到不稳定的感觉运动语言系统的影响。重要的是，有人提出外显学习依赖于稳定的内部运动模型的建立。如果不这样做，可能会导致语音流畅性中断。解开内隐和外显运动学习在口吃发展中的独特贡献，对于理解这种言语流利性障碍至关重要。这项拟议的项目概述了旨在调查口吃儿童和成年人的运动学习技能的研究。该项目将有助于我们对口吃的本质和发展的理解，并将为正在进行的语音运动控制模型的改进提供信息。