MRC/UCT Medical Imaging Research Unit, Faculty of Health Sciences, University of Cape Town, Observatory, South Africa.
Pediatr Neurol. 2012 Feb;46(2):94-100. doi: 10.1016/j.pediatrneurol.2011.11.019.
This study compared brain activation during unpaced rhythmic finger tapping in 12-year-old children with that of adults. Subjects pressed a button at a pace initially indicated by a metronome (12 consecutive tones), and then continued for 16 seconds of unpaced tapping to provide an assessment of their ability to maintain a steady rhythm. These analyses focused on the superior vermis of the cerebellum, which is known to play a key role in timing. Twelve adults and 12 children performed this rhythmic finger tapping task in a 3 T scanner. Whole-brain analyses were performed in Brain Voyager, with a random-effects analysis of variance using a general linear model. A dedicated cerebellar atlas was used to localize cerebellar activations. As in adults, unpaced rhythmic finger tapping in children demonstrated activations in the primary motor cortex, premotor cortex, and cerebellum. However, overall activation was different, in that adults demonstrated much more deactivation in response to the task, particularly in the occipital and frontal cortices. The other main differences involved the additional recruitment of motor and premotor areas in children compared with adults, and increased activity in the vermal region of the cerebellum. These findings suggest that the timing component of the unpaced rhythmic finger tapping task is less efficient and automatic in children, who need to recruit the superior vermis more intensively to maintain the rhythm, although they performed somewhat more poorly than adults.
本研究比较了 12 岁儿童和成年人在无节奏手指敲击时大脑的激活情况。受试者先按照节拍器（连续 12 个音）的指示按下按钮，然后进行 16 秒的无节奏敲击，以评估他们维持稳定节奏的能力。这些分析集中在小脑的上蚓部，该部位已知在计时方面起着关键作用。12 名成年人和 12 名儿童在 3T 扫描仪中执行了这项节奏性手指敲击任务。全脑分析在 Brain Voyager 中进行，采用一般线性模型的随机效应方差分析。使用专门的小脑图谱来定位小脑激活。与成年人一样，儿童的无节奏手指敲击也表现出初级运动皮层、运动前皮层和小脑的激活。然而，总的激活情况不同，因为成年人对任务的反应有更多的去激活，特别是在枕叶和额叶皮层。其他主要差异涉及与成年人相比，儿童更多地招募运动和运动前区域，以及小脑蚓部区域的活动增加。这些发现表明，无节奏手指敲击任务的计时成分在儿童中效率较低且不自动，儿童需要更密集地募集上蚓部来维持节奏，尽管他们的表现略逊于成年人。
