Reed Jamie L, Pouget Pierre, Qi Hui-Xin, Zhou Zhiyi, Bernard Melanie R, Burish Mark J, Haitas John, Bonds A B, Kaas Jon H
Neuroscience Graduate Program, Vanderbilt Brain Institute, U1205 Medical Center North, Vanderbilt University, Nashville, TN 37235-2050, USA.
Proc Natl Acad Sci U S A. 2008 Jul 22;105(29):10233-7. doi: 10.1073/pnas.0803800105. Epub 2008 Jul 15.
Tactile discrimination depends on integration of information from the discrete receptive fields (RFs) of peripheral sensory afferents. Because this information is processed over a hierarchy of subcortical nuclei and cortical areas, the integration likely occurs at multiple levels. The current study presents results indicating that neurons across most of the extent of the hand representation in monkey primary somatosensory cortex (area 3b) interact, even when these neurons have separate RFs. We obtained simultaneous recordings by using a 100-electrode array implanted in the hand representation of primary somatosensory cortex of two anesthetized owl monkeys. During a series of 0.5-s skin indentations with single or dual probes, the distance between electrodes from which neurons with synchronized spike times were recorded exceeded 2 mm. The results provide evidence that stimuli on different parts of the hand influence the degree of synchronous firing among a large population of neurons. Because spike synchrony potentiates the activation of commonly targeted neurons, synchronous neural activity in primary somatosensory cortex can contribute to discrimination of complex tactile stimuli.
触觉辨别依赖于来自外周感觉传入神经离散感受野（RFs）的信息整合。由于该信息在皮质下核团和皮质区域的层级结构中进行处理，这种整合可能发生在多个层面。当前研究呈现的结果表明，在猴初级体感皮层（3b区）手部表征的大部分范围内，神经元之间存在相互作用，即便这些神经元具有各自独立的感受野。我们通过将一个100电极阵列植入两只麻醉的猫头鹰猴初级体感皮层的手部表征区域，进行同步记录。在一系列使用单探针或双探针进行的0.5秒皮肤压痕实验中，记录到具有同步放电时间的神经元的电极之间的距离超过了2毫米。这些结果提供了证据，表明手部不同部位的刺激会影响大量神经元之间的同步放电程度。由于放电同步增强了共同靶向神经元的激活，初级体感皮层中的同步神经活动有助于复杂触觉刺激的辨别。
