Schwabe Lars, Obermayer Klaus
Berlin University of Technology, Department of Computer Science and Electrical Engineering, Franklin Str. 28/29, 10587 Berlin, Germany.
Vision Res. 2005 Nov;45(25-26):3202-9. doi: 10.1016/j.visres.2005.05.028. Epub 2005 Jul 22.
We propose that the effects of attentional top-down modulations observed in the visual cortex reflect the simple strategy of strengthening currently relevant pathways in a task-dependent manner. To exemplify this idea, we set up a network model of a visual area and simulate the learning of a context-dependent 'go/no-go'-task. The model learns top-down gain-modulations of sensory representations based on reinforcements received from the environment. We also discuss how this idea relates to alternative interpretations like optimal coding hypotheses.
我们提出,在视觉皮层中观察到的注意力自上而下调制效应反映了一种简单的策略,即以任务依赖的方式强化当前相关的通路。为了例证这一观点,我们建立了一个视觉区域的网络模型,并模拟了一种依赖上下文的“是/否”任务的学习过程。该模型基于从环境中接收到的强化信息来学习感觉表征的自上而下增益调制。我们还讨论了这一观点与诸如最优编码假设等其他解释之间的关系。