de Klerk Carina C J M, Johnson Mark H, Southgate Victoria
Centre for Brain and Cognitive Development, Birkbeck College, University of London, United Kingdom.
Centre for Brain and Cognitive Development, Birkbeck College, University of London, United Kingdom.
Dev Cogn Neurosci. 2015 Oct;15:1-10. doi: 10.1016/j.dcn.2015.08.004. Epub 2015 Aug 17.
Previous studies have shown that sensorimotor cortex activation is somatotopically-organised during action execution and observation in adulthood. Here we aimed to investigate the development of this phenomenon in infancy. We elicited arm and leg actions from 12-month-old infants and presented them, and a control group of adults, with videos of arm and leg actions while we measured their sensorimotor alpha suppression using EEG. Sensorimotor alpha suppression during action execution was somatotopically organised in 12-month-old infants: there was more suppression over the arm areas when infants performed reaching actions, and more suppression over the leg area when they performed kicking actions. Adults also showed somatotopically-organised activation during the observation of reaching and kicking actions. In contrast, infants did not show somatotopically-organised activation during action observation, but instead activated the arm areas when observing both reaching and kicking actions. We suggest that the somatotopic organisation of sensorimotor cortex activation during action observation may depend on infants' understanding of the action goal and their expectations about how this goal will be achieved.
先前的研究表明，在成年期的动作执行和观察过程中，感觉运动皮层的激活是按躯体定位组织的。在此，我们旨在研究这一现象在婴儿期的发展情况。我们诱发了12个月大婴儿的手臂和腿部动作，并在测量他们使用脑电图的感觉运动α波抑制情况时，向他们以及一组成年对照组展示手臂和腿部动作的视频。在动作执行过程中，12个月大婴儿的感觉运动α波抑制是按躯体定位组织的：当婴儿执行够物动作时，手臂区域的抑制更强；当他们执行踢腿动作时，腿部区域的抑制更强。成年人在观察够物和踢腿动作时也表现出按躯体定位组织的激活。相比之下，婴儿在动作观察过程中并未表现出按躯体定位组织的激活，而是在观察够物和踢腿动作时均激活了手臂区域。我们认为，动作观察过程中感觉运动皮层激活的躯体定位组织可能取决于婴儿对动作目标的理解以及他们对如何实现这一目标的预期。
