The primary visual cortex processes a large amount of visual information, however, due to its large receptive fields, when multiple stimuli fall within one receptive field, there are computational problems. To solve this problem, the visual system uses selective attention, which allocates resources to a specific spatial location, to attend to one of the stimuli in the receptive field. During this process, the center and width of the attending receptive field change. The model presented in the paper, which is extended and altered from Bobier et al., simulates the selective attention between the primary visual cortex, V1, and middle temporal (MT) area. The responses of the MT columns, which encode the target stimulus, are compared to the results of an experiment conducted by Womelsdorf et al. on the receptive field shift and shrinkage in macaque MT area from selective attention. Based on the results, the responses in the MT area are similar to the Gaussian shaped receptive fields found in the experiment. As well, the responses of the MT columns are also measured for accuracy of representing the target visual stimulus and is found to represent the stimulus with a root mean squared error around 0.17 to 0.18. The paper also explores varying model parameters, such as the membrane time constant and maximum firing rates, and how those affect the measurement. This model is a start to modeling the responses of selective attention, however there are still improvements that can be made to better compare with the experiment, produce more accurate responses and incorporate more biologically plausible features.
翻译:初级视觉皮层处理大量的视觉信息,然而,由于它是一个可接受字段,当多个刺激因素出现在一个可接受字段内时,存在计算问题。为了解决这个问题,视觉系统使用选择性的注意,将资源分配到特定的空间位置,以关注可接受字段中的刺激因素之一。在此过程中,主可接受字段变化的中心与宽度。文件中显示的模型,从Bobier 等人 得到扩展和修改,模拟了主要视觉皮层、V1和中间时空(MT)区域之间的选择性注意。MT列中标集目标刺激因素,其反应与Womelsdorf 等人(Womelsdorf et al.) 进行实验的结果相比较,将资源分配到特定空间位置,从而关注可满足一个可接受字段中的某一刺激因素。在此过程中,MT区域的反应可以类似于实验中发现的高斯模式的可接受字段。此外,MT列的反应也测量了目标视觉刺激因素的准确性反应,比较性指标性特征,将目标刺激刺激因素的参数与Womelsdorizdal imbal imal imal imal imal deal resear made made made made the made the made the more made the more roductions made the made the made thes made the made the she made a made a made a made a made a made a made a made a made a ligrealdaldal be rode.