双眼竞争（Binocular rivalry）是指进入左眼和右眼中的图像在我们感觉中交替呈现的一种视觉现象。在同一时刻，给两只眼睛呈现差异很大的两幅图像，就会发现我们感觉到的并不是这两幅图像的合成版，而是一会呈现一只眼睛的图像，一会又呈现另外一只眼睛的图像，这种感觉不停的交替呈现。举个例子，给左眼中呈现一幅竖条纹的图像，给右眼呈现水平条纹的图像，就会发现看到的要幺都是横条纹，要幺都是竖条纹。在两幅图像交替呈现的过渡期，有可能看到两幅图像合成出的一幅不稳定图像，但这种情况通常是有次序的。比如说，在一定时间之内，横条纹总是从左面或者右面遮挡竖条纹，或者竖条纹总是从上面或下面遮挡横条纹。双眼竞争一般在左右眼的图像差别足够大的时候发生，简单的情况如不同空间方位的线条组成的图像，复杂的情况如不同的字母或者不同的图片，如人脸与房子。

Binocular rivalry is a phenomenon of visual pe****tion in which pe****tion alternates between different images presented to each eye .

When one image is presented to one eye and a very different image is presented to the other (also known as dichoptic presentation), instead of the two images being seen superimposed, one image is seen for a few moments , then the other, then the first, and so on, randomly for as long as one cares to look. For example, if a set of vertical lines is presented to one eye, and a set of horizontal lines to the same region of the retina of the other, sometimes the vertical lines are seen with no trace of the horizontal lines, and sometimes the horizontal lines are seen with no trace of the vertical lines.