Dynamic and distributed properties of many-neuron ensembles in the ventral posterior medial thalamus of awake rats.
Dynamic and distributed properties of many-neuron ensembles in the ventral posterior medial thalamus of awake rats.
复制标题
清醒大鼠腹侧后内侧丘脑多神经元群的动态和分布特性。
DOI：
10.1073/pnas.90.6.2212
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发表时间：
1993
影响因子：
11.1
通讯作者：
Chapin,JK
中科院分区：
文献类型：
--
作者：
Nicolelis,MA;Lin,RC;Woodward,DJ;Chapin,JK
传统的观点认为，丘脑腹侧后内侧(VPM)的脸部地图是静态的，高度离散的，这在很大程度上源于定性研究，这些研究只报道了小的、健壮的和不重叠的感受野(RF)。在这里，通过使用更多的定量技术，我们为另一种假设提供了证据：VPM中的RF很大且重叠，并倾向于随着刺激后时间的变化而移动。这些结果是通过同时记录大鼠VPM中的胡须代表区多达23个单个神经元获得的。在清醒和麻醉状态下，这些神经元在短潜伏期(4-6ms)和/或长潜伏期(15-25ms)对单个面须的离散振动机械刺激反应强烈。计算机图形学被用来构建三维曲线图，描绘作为刺激后时间的函数的神经元对几个胡须刺激的反应的大小。这些“时空RFs”表明：(I)VPM神经元的RFs相当大，覆盖多达20个胡须；(Ii)这些RFs的空间位置在刺激后的前35ms内可能发生剧烈的移动，特别是从面部最尾部的胡须到最顶部的胡须。这些结果表明，VPM包含了人脸的动态和分布表示，其中刺激信息在空间域和时间域中都被编码。
The traditional view that the map of the face in the ventral posterior medial thalamus (VPM) is static and highly discrete was derived largely from qualitative studies that reported only small, robust, and nonoverlapping receptive fields (RFs). Here, by using more quantitative techniques, we have provided evidence for an alternative hypothesis: the RFs in the VPM are large and overlapping and tend to shift as a function of post-stimulus time. These results were obtained through simultaneous recordings of up to 23 single neurons across the whisker representation in the VPM of rats. Under both awake and anesthetized conditions, these neurons responded robustly at short (4-6 ms) and/or long (15-25 ms) latencies to discrete vibromechanical stimulation of single facial whiskers. Computer graphics were used to construct three-dimensional plots depicting the magnitudes of neuronal responses to stimulation of each of several whiskers as a function of post-stimulus time. These "spatiotemporal RFs" demonstrated that (i) the RFs of VPM neurons are quite large, covering up to 20 whiskers and (ii) the spatial locations of these RFs may shift dramatically over the first 35 ms of post-stimulus time, especially from the caudal-most to the rostral-most whiskers on the face. These results suggest that the VPM contains a dynamic and distributed representation of the face, in which stimulus information is coded in both spatial and temporal domains.