据seedmagazine网站2006年8月3日报道，研究人员发现，对事物的熟悉程度是记忆能力的关键。
闭上您的眼睛，想象一下“马铃薯”这个单词。好了，睁开眼睛。现在再闭上您的眼睛，想象一下“边门”这个单词。在想象第二个单词时您可能需要稍长的时间——为了不会让您毫无头绪，给您一点提示，它是指一种小门。根据卡内基梅隆大学的新研究结果推断，如果让您第二天回忆这两个单词，您可能很快就会记起第一个单词。
该大学的研究小组为了研究新记忆是怎样形成的，对一组患有药物性暂时健忘症的研究对象进行了类似询问。
他们发现，研究新记忆的形成最终关系到人们将新信息与之前经历相互联系起来的能力：就文章开篇所举的例子来说，普通人吃马铃薯的经历要远远多于爬过小门的经历。
“一个人将某件事物与背景相互结合的能力在于它是‘块’还是‘组’，”相关研究报告的首席作者、心理学家李恩"瑞德表示，这一报告发表在《心理科学》的7月版。
当一些互不相关的信息被认为是属于一组时，就会形成“块状”信息。例如，三个字母组合在一起的单词“FBI” ——而不是“SVQ”或者“TMY”这样的组合，即块状信息，因为这是一个组织的名称缩写，我们时常会听到它。因为无须逐个破译这些块状信息，所以它们不会占用太多的脑力资源来破译。但是，当信息不是块状时，也就无法与相应的背景所联系起来，而这正是记忆的要素。
为了验证这一概念，研究人员向研究对象注射了安慰剂盐水或咪达唑仑（一种能够导致暂时健忘症的药剂），然后向他们展示一系列单词与图片，这些图片有十分常见的也有抽象的，包括面孔、景色以及奇怪的形状。（咪达唑仑一般在临床手术中用来缓解焦虑，最近才被科学家们应用到了研究中。
研究人员发现，研究对象被注射了咪达唑仑后，回忆单词的能力所受到的削弱要大于回忆图片与风景。但是，无论是被注射了药剂还是咪达唑仑，在回忆抽象图片时，都会遇到困难。瑞德相信，这是因为抽象图片不是块状的原因。“破译那些抽象图片可不容易，”瑞德说。“然而，如果它是一幅毕加索的名画《格尔尼卡》或是埃菲尔铁塔，您就会把它的信息储存起来，然后与（之前您看到这幅图片时）相应的背景联系起来。这样一来您就不必花费大量的时间为它生成一个记忆标签。”
乔治华盛顿大学的心理学家艾略特"哈什曼同样在研究咪达唑仑对记忆力的影响，他表示，卡内基梅隆大学的研究结果实在是令人惊讶。他指出，其它研究的确显示出图片与文字相比具有更强的刺激性，而且在患有健忘症时，也更有可能会从记忆中唤起。
“从常识角度来看，您会认为，如果并不熟悉信息，那么它应该在您的记忆中十分明显，使您更牢地记住它，”他表示。“另一方面，一种更为复杂的观点认为，如果刺激信息的各个不同方面在某种程度上并不相关，回忆它会更加困难。”
这一发现能够帮助人们对顺行性健忘患者有一个更好地了解，这类病人的旧记忆完整无缺，但是由于他们无法在记忆中记录新的经历，所以在形成新记忆时会遇到一些困难。
有意思的是，如果对刺激信息足够熟悉，那么这些病人可能会利用旧记忆来形成新记忆。
“虽然人们认为健忘症患者无法回忆起任何事情，”瑞德表示，“但是事实并非如此。
英文原文：
ＨＯＷ ＷＥ ＭＡＫＥ Ａ ＭＥＭＯＲＹ
Researchers find that familiarity is the touchstone for being able to remember.
Close your eyes and think about the word "potato." Okay, open them. Now, close your eyes and think about the word "wicket."
Chances are you took a little longer with the second one—it's a small door or gate, in case you were drawing a complete blank.
If you were asked to recall these two words tomorrow, according to new research from Carnegie Mellon University, chances are you'd be quicker to remember the first.
Asking a group of subjects who were experiencing temporary, drug-induced amnesia to perform similar exercises, the Carnegie Mellon team attempted to determine how we form new memories.
They found that the process comes down to our ability to link new information to prior experiences: In the case of the introductory example, the average person has probably had more practice eating potatoes than climbing through wickets.
"One's ability to associate something to a context depends on it being a 'chunk' or unit," said psychologist Lynne Reder, lead author of the study, which appears in the July issue of Psychological Science.
"Chunking" occurs when otherwise unrelated items are perceived as a unit. For example, the three-letter combination FBI—but not, say, SVQ or TMY—is chunked because it's associated with an entity, and we hear the grouping so often. Items that are chunked take up less of our mental resources to encode since each item doesn't have to be encoded separately.
But when something is not a chunk, it can't be bound to a context, which is important for memory.
To test this concept, the researchers showed a series of words and pictures—the latter ranging from familiar to abstract, including faces, landscapes and nondescript markings—to their subjects after injecting them with either a saline placebo or midazolam, a drug that causes temporary amnesia. (Midazolam is routinely used in surgical procedures to relieve anxiety, and has recently been adopted by researchers for studying memory.)
The researchers found that, under midazolam, subjects were more impaired in their ability to remember words than photos of faces and landscapes. But both subjects who received the drug and the placebo had difficulty remembering the abstract pictures. Reder believes that this is because the abstract pictures cannot be chunked.
"For these abstract pictures, it's hard to encode them," Reder said, "Whereas if it was a picture of [Pablo Picasso's] Guernica or the Eiffel Tower, you could store it away and bind it to the context in which you saw the picture [previously]. You wouldn't have to spend a lot of time staring at it to generate a label for it."
The results of the Carnegie Mellon study are surprising, said George Washington University psychologist Elliot Hirshman, who also studies the effects of midazolam on memory. He points out that other studies have actually shown pictures to be stronger stimuli than words, and therefore more likely to be recalled under the effects of amnesia.
"From a common sense perspective, you might think that if something's unfamiliar, then it should really stand out in your memory, and you might remember it better," he said. "On the other hand, a more sophisticated view is that if the different parts of a stimulus don't cohere in some sense, it'll be harder to recover them."
The findings could lead to a better understanding of patients with anterograde amnesia, those who may have trouble making new memories because they can't record new experiences even though their old memories are still intact. Intriguingly, if the stimuli are sufficiently familiar, these same patients may be able to access old memories in order to make new ones.
"Although people claim that amnesiacs can't remember anything," Reder said, "that's actually not true."
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