学进去

Many of us learn how to ride a bicycle at a young age. As we grow older, we may stop riding—most of us go to school by bus or by subway. But whenever we get on a bicycle, it’s like we’ve never stopped biking. This is strange. In many other cases, our memories let us down. We often find it hard to remember the name of a person or a place, don’t we? So why can we still ride a bicycle after we stopped riding a long time ago?

It turns out that there are many types of memories. They are stored in different regions of our brains. Memories of experiences (e.g., our first day at school) and of factual (事实的) knowledge (e.g, the capital of France) are declarative memories. These memories can be communicated to others. Skills such as playing an instrument or riding a bike are procedural memories. These memories are responsible for our performance.

Scientists have done many experiments on different memory types. Perhaps the most famous of them was carried out on Henry Gustav Molaison, an epileptic(癫痫患者). In an operation in the 1950s, part of his brain was taken away. After that, the man suffered less from epilepsy. But there was a new problem! Molaison’s memory system went wrong. Through various tests, scientists found he could learn new skills (slowly, though). However, he could never remember having been trained to learn a new skill. In other words, Molaison could develop new procedural, but not declarative, memories.

Scientists have concluded that even with serious brain injuries, procedural memories last much longer. However, they haven’t yet found out why. Some say procedural memories are more lasting because they are stored in the brain’s center.

Now, “It is just like riding a bicycle” has been used as an idiom(习语) in our daily life.

1．In the first paragraph, the writer leads into the topic by ________.

A．listing numbers	B．giving examples
C．describing scenes	D．explaining reasons

2．Which of the following is about a procedural memory?

A．The climate of Asia.	B．A birthday party with friends.
C．A trip to the USA.	D．Swimming.

3．What might be Henry Gustav Molaison’s new problem after the operation in the 1950s?

A．He couldn’t remember anything.	B．He couldn’t learn a new skill.
C．He couldn’t remember factual knowledge.	D．He suffered more from epilepsy.

4．The idiom “It is just like riding a bicycle” probably means “________.”

A．Once learned, it is never forgotten	B．It’s never too late to learn
C．You should learn with all your heart	D．People can learn from their mistakes