Passage Two
The brain is a seemingly endless library, whose shelves house our most precious memories as well as our lifetime's knowledge. But is there a point where it reaches capacity?
The answer is no, because brains are more sophisticated than that. Instead of just crowding in, old information is sometimes pushed out of the brain for new memories to form.
Previous behavioural studies have shown that learning new information can lead to forgetting. But in a new study, researchers demonstrated for the first time how this effect occurs in the brain.
In daily life, forgetting actually has clear advantages. Imagine, for instance, that you lost your bank card. The new card you receive will come with a new personal identification number (PIN). Each time you remember the new PIN, you gradually forget the old one. This process improves access to relevant information, without old memories interfering.
And most of us may sometimes feel the frustration of having old memories interfere with new, relevant memories. Consider trying to remember where you parked your car in the same car park you were at a week earlier. This type of memory (where you are trying to remember new, but similar information) is particularly vulnerable to interference.
When we acquire new information, the brain automatically tries to incorporate (合并) it within existing information by forming associations. And when we retrieve (检索) information, both the desired and associated but irrelevant information is recalled.
The majority of previous research has focused on how we learn and remember new information. But current studies are beginning to place greater emphasis on the conditions under which we forget, as its importance begins to be more appreciated.
A very small number of people are able to remember almost every detail of their life. While it may sound like an advantage to many, people with this rare condition often find their unusual ability burdensome.
In a sense, forgetting is our brain's way of sorting memories, so the most relevant memories are ready for retrieval. Normal forgetting may even be a safety mechanism to ensure our brain doesn't become too full.
What have past behavioural studies found about our brain?
细节题。第二段最后一句指出，旧信息有时候会被挤出大脑以形成新的记忆，而不是仅仅挤进去。第三段第一句指出，之前的行为研究已经表明，学习新信息会导致遗忘。新信息把旧信息挤出去的过程事实上就是遗忘。D项和原文相符，故答案为D。A项和原文不符，原文第一段最后一句提到大脑容量是否有临界点这一问题，第二段开头给出了否定的回答，即大脑容量是没有临界点的，但是文中并没有说这是过去的行为研究发现的，故排除。B、C项原文均未提及，故排除。
What is the benefit of forgetting?
细节题。第四段最后一句指出，在没有旧的记忆的干扰下，这个过程改进了对相关信息的访问。这句话中的this process对应的就是forgetting，也就是说，遗忘改进了对相关信息的访问，C项与原文相符，故答案为C。A、B项原文均未提及，故排除。D项与原文不符，原文指的是遗忘可以改进对相关信息的访问，并不是防止旧信息形成关联，故排除。
What is the emphasis of current studies of memory?
推理题。第七段最后一句指出，现在的研究开始把重点放在遗忘的条件上，因为它的重要性开始受到重视。由此可推断出，当前记忆研究的重点是什么情况会导致遗忘，故答案为B。原文未涉及遗忘容易发生的时间，故排除A项。原文未涉及新技术的话题，故排除C项。原文未涉及学习和遗忘的话题，故排除D项。
What do people find about their rare ability to remember every detail of their life?
细节题。第八段最后一句指出，虽然这听起来对大多数人来说像是一个优势，但有这种罕见情况的人往往会发现他们的这种不寻常的能力令人难以承受。A项中的burden对应原文第八段最后一句话中的burdensome，A项与原文相符，故答案为A。B、C、D项原文均未提及，故排除。
What does the passage say about forgetting?
细节题。最后一段第一句指出，从某种意义上说，遗忘是我们大脑对记忆进行排序的方式。C项中说遗忘是一种组织记忆的方式，与原文相符，故答案为C。原文未提及遗忘可以扩大脑容量，故排除A项。原文未提及遗忘会帮助消除消极的记忆，故排除B项。D项原文未提及，故排除。