Visual processing of contours and textures

这个应用程序是资金继续我的研究到视觉处理的轮廓和纹理。 能够处理轮廓的形状，如梨的弯曲轮廓，以及纹理，如折叠地毯的表面，是我们识别视觉世界中物体和表面形状的能力的重要组成部分。 我的实验涉及人类测试对象观看大量专门设计的计算机生成的测试模式显示在显示器上，并对它们做出判断。我目前采用的特殊实验方法是“视觉后效”。 对特定轮廓/纹理形状的长时间观察（称为“自适应”）会导致其他轮廓/纹理形状出现扭曲。 通过测量失真的量，可以了解大脑如何处理轮廓/纹理形状。 例如，如果一个人采取一个简单的弯曲轮廓，并适应它，一个稍微弯曲的轮廓似乎比其他更弯曲。 这种效应被称为“曲率后效应”，它的发生告诉我们，大脑中有专门用于看到曲线的神经元。 因此，曲率后效可以用来揭示大脑如何看待曲线的细节。 举一个例子来说明它是如何做到这一点的，我的实验室已经证明，如果适应曲线和测试曲线是不同的颜色，那么与相同颜色相比，曲率后效会大大减少（即失真更少）。 这告诉我们，大脑中检测曲线的神经元对颜色进行了“调整”，换句话说，一些神经元对红色曲线，一些绿色曲线，一些蓝色曲线等做出反应。 与其他实验一起，我的研究因此导致更好地理解大脑如何看到轮廓和纹理的形状。

This application is for funds to continue my research into the visual processing of contours and textures. Being able to process the shapes of contours, such as a curved outline of a pear, as well as textures, such as the surface of a folded carpet, is an essential part of our ability to recognize objects and the shapes of surfaces in the visual world. My experiments involve human test subjects viewing large numbers of specially-designed computer-generated test patterns presented on a display monitor and making judgements about them. The particular experimental method I current employ is the 'visual after-effect'. Prolonged viewing, termed 'adaptation', of a particular contour/texture shape causes other contour/texture shapes to appear distorted. By measuring the amount of distortion, a great deal can be learnt about how the brain processes contour/texture shapes. For example, if one takes a simple curved contour and adapts to it, a slightly more curved contour appears even more curved than otherwise. This effect is termed the 'curvature after-effect', and the fact that it happens at all tells us that there are neurons in the brain that are specialized for seeing curves. Thus the curvature after-effect can be used to uncover the details of how the brain sees curves. To take one example of how it can do this, my lab has shown that if the adaptation and test curves are a different colour the curvature after-effect is much reduced (i.e. there is less distortion) compared to if they are the same colour. This tells us that the neurons in the brain that detect curves are 'tuned' for colour, in other words some neurons respond to red curves, some green curves, some blue curves etc. Together with other experiments, my research therefore leads to a better understanding of how the brain sees the shapes of contours and textures.