For some time past, it has been widely accepted that babies－and other creatures－learn to do things because certain acts lead to “ rewards ”, and there is no reason to doubt that this is true. But it used also to be widely believed that effective rewards, at least in the early time, had to be directly connected to such basic physiological（生理的）“drives” as thirst or hunger. In other words, a baby would learn if he got food or drink or some sort of physical comfort, not otherwise.

It is now clear that this is not so. Babies will learn to behave in ways that produce results in the world with no rewards except success in sight.

Papousek began his studies by using milk in the normal way to “reward” the babies and to teach them to carry out some simple movements, such as turning the head to one side or the other. Then he noticed that a baby who had had enough to drink would refuse the milk but would still go on making the learned response with clear signs of pleasure. So he began to study the children’s responses in situations where no milk was provided. He quickly found that children as young as four months would learn to turn their heads to right or left if the movement “turned on” some lights－and indeed that they were able to learn quite complex turns to bring about this result, for example, two left or two right, or even to make as many as three turns to one side.

Papousek’s light experiment was placed directly in front of the babies and he made the interesting observation that sometimes they would not turn back to watch the light closely although they would “smile and bubble” when the light was on. Papousek concluded that it was not the sight of the lights which pleased them; it was the success they were achieving in solving the problem, in mastering the skill, and that there exists a basic human desire to make sense of the world and bring it under intended control.

56. The author uses the widely accepted concept to start with the passage in order to _______ .

A. arouse the readers’ interest            

B. make readers understand the new discovery smoothly

C. serve as a base to start his new discovery

D. encourage readers to raise questions

57. Which of the following is NOT the key factor in Papousek’s study?

A. The research method from milk to light.

B. The different responses of the babies.

C. The discovery of the result is not the reward.

D. The place or situations where the display is conducted.

58. The reason for the babies smiling and bubbling in Paragraph 4 is probably that _______.

   A. the can watch the lights closely and curiously

B. they are offered milk as “reward”

C. they succeed in “turning on” the lights

D. the lights serve as basic “drives”

59. The pleasure the babies showed is a reflection of _______.

 A. basic physiological “drives”

B. a basic human desire to understand and control the world

C. some sort of physical comfort

D. a basic desire to show their learned skills