If the baby really sees it as different, the baby will look longer, and you could use that as a measure of what babies find different.

如果婴儿认为此物与之前出现物体不同,婴儿的注视时间会变长,你可以将注视时间变长,视为婴儿发现物体间区别的一种标志

耶鲁公开课 - 心理学导论课程节选

And I have here two ways you could learn from looking.

你可以通过两种方法,从注视这个动作中得出一些结论

耶鲁公开课 - 心理学导论课程节选

If you sit in your chairs and look at this keyboard, and relax your muscles and imagine moving your right arm up and hitting the "s" key.

当你坐在椅子上，注视着电脑键盘，放松肌肉,想象你抬起右臂敲击，S，键。

斯坦福公开课 - 7个颠覆你思想的演讲课程节选