Questions  are based on the recording you have just heard.
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OK. I will bet for most of you your earliest memory would be from about age 3, right? Well, that's true for most adults. We can't remember anything that happened before the age of 3. And this phenomenon is so widespread and well-documented it has a name. It's called childhood amnesia. As I said, this phenomenon refers to adults not being able to remember childhood incidents. So... [20] Why is this? What are the reasons for childhood amnesia? There are various explanations, but all the evidences seem not so powerful. Anyhow, let's put that explanation aside and concentrate on just two. OK? It could be that as children we do form memories of things prior to age 3, but forget them as we grow older. Another possibility is that children younger than 3 lack some captive capacity for memory. And that idea, that children are unable to form memories. That's been the dominant belief in psychology for the past 20 years. And this idea is very much tied to two things, the theories of Jean Piaget and also to language development in children. So Piaget's theory of cognitive development --Piaget suggested that because they don't have language, children younger than 18-24 months live in the here and now, that is, they lack the means to symbolically represent objects, and events, that are not physically present.
Well, finally in the 1980s, a study was done. And this study showed that very young children, under the age of 2,do have the capacity for recall. Now if the children can't talk, how was recall tested? Well, since the capacity for recall has always been linked with the ability to talk. [21] So the researchers set up an experiment using imitation-based tasks. Adults use toys or other objects to demonstrate an action that has 2 steps. The children were asked to imitate the steps immediately and then again after delays of one or more month. And even after a delay, the children could...could recall or perform the action, the objects used, the steps involved and the order of the steps. Even children as young as 9 months, now, tests showed that there was a faster way to forgetting among the youngest children, [22] but most importantly it showed that the development of recall did not depend only on language development. And that was an importance finding.
So, back to our question about the cause of childhood amnesia. Well, there is something called the rate off or getting. And childhood amnesia may reflect a high rate of forgetting, in other words, children under the age of 3 do form memories and do so without language. But they forget the memories at a fast rate, probably faster than adults do.
【预测】选项中的proved or disproved，without proper evidence，explain only certain types和contradicted表明，本题可能考查they的不足之处，they指某些研究
【解析】B。录音中教授提到，关于童年记忆缺失的原因有很多解释，但是证据都不太充分（ evidences seem not so powerful）。B是对该观点的同义转述，故为答案