Executed and Observed Movements Have Different Distributed Representations in Human aIPS
Executed and Observed Movements Have Different Distributed Representations in Human aIPS
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DOI：
10.1523/jneurosci.3585-08.2008
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发表时间：
2008-10-29
影响因子：
5.3
通讯作者：
Heeger, David J.
中科院分区：
文献类型：
--
作者：
Dinstein, Ilan;Gardner, Justin L.;Heeger, David J.
在人脑中执行的和观察到的手部运动的表征有多相似？我们使用功能性磁共振成像（fMRI）和多元模式分类分析来比较几个观察和执行运动的皮层活动的空间分布。受试者与录像中的对手玩石头剪子布游戏，在每次试验中自由选择自己的动作，并在短暂的延迟后观察对手的手部动作。从运动皮层的几个区域的fMRI反应中正确地区分了执行运动的身份，从视觉皮层的反应中区分了观察到的运动，并且从左或右前顶叶内沟（aIPS）的反应中区分了观察到的和执行的运动。我们将上述偶然分类解释为可重复的、分布的皮层活动模式的证据，这些模式对于执行和/或观察每个动作来说是独一无二的。aIPS中的反应能够在每个模态（视觉或运动）中对运动身份进行准确分类，但不能跨模态进行准确分类（即，从执行运动训练的分类器中解码观察到的运动，反之亦然）。这些结果支持了aIPS在运动感知和执行中的核心作用的理论。然而，观察到的特定运动的活动空间模式与执行时的相同运动明显不同，这表明观察到的和执行的运动主要由aIPS中明显不同的神经元亚群代表。
How similar are the representations of executed and observed hand movements in the human brain? We used functional magnetic resonance imaging (fMRI) and multivariate pattern classification analysis to compare spatial distributions of cortical activity in response to several observed and executed movements. Subjects played the rock-paper-scissors game against a videotaped opponent, freely choosing their movement on each trial and observing the opponent's hand movement after a short delay. The identities of executed movements were correctly classified from fMRI responses in several areas of motor cortex, observed movements were classified from responses in visual cortex, and both observed and executed movements were classified from responses in either left or right anterior intraparietal sulcus (aIPS). Weinterpret above chance classification as evidence for reproducible, distributed patterns of cortical activity that were unique for execution and/or observation of each movement. Responses in aIPS enabled accurate classification of movement identity within each modality (visual or motor), but did not enable accurate classification across modalities (i.e., decoding observed movements from a classifier trained on executed movements and vice versa). These results support theories regarding the central role of aIPS in the perception and execution of movements. However, the spatial pattern of activity for a particular observed movement was distinctly different from that for the same movement when executed, suggesting that observed and executed movements are mostly represented by distinctly different subpopulations of neurons in aIPS.