Area 3b hand cortex in primate: the targets and sources of extra-hand suppressive surrounds

总结 我们以前的研究已经揭示了一个复杂的组织的感受野（RF）的神经元在初级 猴的躯体感觉皮层（3b区）。神经元有小的兴奋中心， 手的躯体位置图，包括无毛手的所有其余部分的抑制性环绕，以及 另一方面，包括所有皮肤的较弱的抑制性环绕（“额外的手”环绕）。我们 建议确定不同层中的神经元是否具有相似或不同的环绕物， 从丘脑传递到3b区神经元，而介导不同部分的连接， 周围是直接或间接向3b区手部神经元提供反馈的失活皮质区。在 此外，我们将确定如何从手感觉输入的主要损失，由于选择性脊髓 损伤，改变了剥夺和非剥夺3B手皮质中神经元的中心-周围关系， 即使在3B再激活和手使用的广泛损伤后恢复之后。预期的结果将大大 扩展我们对触觉信息如何在体感中处理的理解 系统，以及如何处理受损和恢复后的感觉损失。这些结果将有一个明确的 对脊髓损伤后治疗干预的影响。

Summary Our previous studies have revealed a complex organization of receptive fields (RFs) of neurons in primary somatosensory cortex of monkeys (area 3b). The neurons have small excitatory centers that create the somatotopic map of the hand, a suppressive surround that includes all of the rest of the glabrous hand, and a weaker suppressive surround that includes all of the skin on the other hand (the “extra hand” surround). We propose to determine if neurons in different layers have similar or different surrounds, what surround features are relayed from the thalamus to area 3b neurons, and the connections that mediate different parts of the surround by inactivating cortical areas that directly or indirectly provide feedback to area 3b hand neurons. In addition, we will determine how a major loss of sensory inputs from the hand, due to selective spinal cord lesions, alters the center-surround relationships of neurons in the deprived and non-deprived 3b hand cortex, even after extensive post lesion recovery of 3b reactivation and hand use. The expected results will greatly expand our understanding of how tactile information from the hands is processed in the somatosensory system, and how processing is impaired and recovered following sensory loss. These results will have a clear impact on therapeutic intervention following spinal cord injury.