Research using clinical populations to explore the relationship between hemispheric speech lateralization and handedness has focused on individuals with speech and language disorders, such as dyslexia or specific language impairment (SLI). Such work reveals atypical patterns of cerebral lateralization and handedness in these groups compared to controls. There are few studies that examine this relationship in people with motor coordination impairments but without speech or reading deficits, which is a surprising omission given the prevalence of theories suggesting a common neural network underlying both functions. We use an emerging imaging technique in cognitive neuroscience; functional transcranial Doppler (fTCD) ultrasound, to assess whether individuals with developmental coordination disorder (DCD) display reduced left‐hemisphere lateralization for speech production compared to control participants. Twelve adult control participants and 12 adults with DCD, but no other developmental/cognitive impairments, performed a word‐generation task whilst undergoing fTCD imaging to establish a hemispheric lateralization index for speech production. All participants also completed an electronic peg‐moving task to determine hand skill. As predicted, the DCD group showed a significantly reduced left lateralization pattern for the speech production task compared to controls. Performance on the motor skill task showed a clear preference for the dominant hand across both groups; however, the DCD group mean movement times were significantly higher for the non‐dominant hand. This is the first study of its kind to assess hand skill and speech lateralization in DCD. The results reveal a reduced leftwards asymmetry for speech and a slower motor performance. This fits alongside previous work showing atypical cerebral lateralization in DCD for other cognitive processes (e.g., executive function and short‐term memory) and thus speaks to debates on theories of the links between motor control and language production.

中文翻译：

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使用功能性经颅多普勒超声证实患有发育协调障碍的成人的非典型言语偏侧化。

利用临床人群探索大脑半球言语偏侧化与利手关系之间的关系的研究主要集中在患有言语和语言障碍（例如阅读障碍或特定语言障碍（SLI））的个体上。这些工作揭示了与对照组相比，这些组的大脑偏侧化和利手性的非典型模式。很少有研究在有运动协调障碍但没有言语或阅读缺陷的人中检验这种关系，考虑到普遍存在的理论表明这两种功能背后有一个共同的神经网络，这是一个令人惊讶的遗漏。我们在认知神经科学中使用一种新兴的成像技术；功能性经颅多普勒（fTCD）超声，用于评估发育性协调障碍（DCD）患者与对照参与者相比，言语产生的左半球偏侧化是否减少。12 名成人对照参与者和 12 名患有 DCD（但没有其他发育/认知障碍）的成人在进行单词生成任务的同时进行 fTCD 成像，以建立用于言语产生的半球偏侧化指数。所有参与者还完成了一项电子钉子移动任务来确定手部技能。正如预测的那样，与对照组相比，DCD 组在言语产生任务中表现出显着减少的左偏化模式。运动技能任务的表现表明两组人都明显偏爱惯用手；然而，DCD 组非惯用手的平均运动时间明显更高。这是第一项评估 DCD 中手部技能和言语偏侧化的研究。结果显示，言语向左不对称性有所减少，运动表现也较慢。这与之前的研究结果相吻合，表明 DCD 中其他认知过程（例如执行功能和短期记忆）的非典型大脑偏侧化，从而引发了关于运动控制和语言产生之间联系的理论争论。