Cortical feedback improves discrimination between figure and background by V1, V2 and V3 neurons
Cortical feedback improves discrimination between figure and background by V1, V2 and V3 neurons
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DOI：
10.1038/29537
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发表时间：
1998-08-20
期刊：
影响因子：
64.8
通讯作者：
Bullier, J
中科院分区：
文献类型：
--
作者：
Hupé, JM;James, AC;Bullier, J
单一视觉刺激会激活许多不同皮质区域的神经元。皮层生理学的一个主要挑战是了解这些众多活动区域的神经活动如何导致视觉场景的统一感知。这些相互作用的解剖学基础是连接视觉区域的密集连接网络。在该网络中，前馈连接将信号从低阶区域（例如 V1 或 V2）传输到高阶区域。此外，还有一个密集的反馈连接网络，尽管它们在解剖学上很突出(1,4)，但在功能上仍然神秘(5-8)。在这里，我们展示了，利用高阶区域（猴子区域 V5/MT）的可逆失活，反馈连接有助于放大和集中低阶区域神经元的活动，并且它们对于区分图形与地面非常重要，特别是在低能见度刺激的情况下。更具体地说，我们表明反馈连接有助于对经典感受野内移动的物体做出反应；增强周围区域背景刺激引起的抑制；并且对低显着性刺激具有最强的效果。
A single visual stimulus activates neurons in many different cortical areas. A major challenge in cortical physiology is to understand how the neural activity in these numerous active zones leads to a unified percept of the visual sct ne. The anatomical basis for these interactions is the dense network of connections that link the visual areas. Within this network, feedforward connections transmit signals from lower-order areas such as V1 or V2 to higher-order areas. In addition, there is a dense web of feedback connections which, despite their anatomical prominence(1,4), remain functionally mysterious(5-8). Here we show, using reversible inactivation of a higher-order area (monkey area V5/MT), that feedback connections serve to amplify and focus activity of neurons in lower-order areas, and that they are important in the differentiation of figure from ground, particularly in the case of stimuli of low visibility. More specifically, we show that feedback connections facilitate responses to objects moving within the classical receptive field; enhance suppression evoked by background stimuli in the surrounding region; and have the strongest effects for stimuli of low salience.