Friday, July 15, 2011

Biological Memory vs. Computer Memory

They are two entirely different things, and this makes all the difference in the world.


by Nicholas Carr


"As gravity holds matter from flying off into space, so memory gives stability to knowledge; it is the cohesion which keeps things from falling into a lump, or flowing in waves." -Emerson

There's a fascinating - and, to me, disquieting - study on the internet's effects on memory that's just come out in Science.* It provides more evidence of how quickly and flexibly our minds adapt to the tools we use to think with, for better or for worse.

The study, "Google Effects on Memory: Cognitive Consequences of Having Information at Our Fingertips," was conducted by three psychologists: Betsy Sparrow, of Columbia University; Jenny Liu, of the University of Wisconsin at Madison; and Daniel Wegner, of Harvard. They conducted a series of four experiments aimed at answering this question: Does our awareness of our ability to use Google to quickly find any fact or other bit of information influence the way our brains form memories? The answer, they discovered, is yes: "when people expect to have future access to information, they have lower rates of recall of the information itself and enhanced recall instead for where to access it." The findings suggest, the researchers write, "that processes of human memory are adapting to the advent of new computing and communication technology."

In the first experiment, people were asked a series of trivia questions. They were then given a test in which they were shown different corporate brand names, some from search engines (eg, Google) and some from other familiar companies (eg, Nike), in different colors and asked to identify the color. In this kind of test, called a Stroop task, a greater delay in naming the color indicates a greater interest in, and cognitive focus on, the word itself. As the researchers explain: "People who have been disposed to think about a certain topic typically show slowed reaction times for naming the color of the word when the word itself is of interest and is more [cognitively] accessible, because the word captures attention and interferes with the fastest possible color naming." The experiment revealed that after people are asked a question to which they don't know the answer, they take significantly longer to identify the color of a search-related brand name than a non-search-related one. The upshot: "It seems that when we are faced with a gap in our knowledge, we are primed to turn to the computer to rectify the situation." There was even a delay, though a lesser one, in identifying the color of an internet brand name when people had been asked questions that they did know the answer to, suggesting that "the computer may be primed when the concept of knowledge in general is activated." In other words, we seem to have trained our brains to immediately think of using a computer when we're called on to answer a question or otherwise provide some bit of knowledge.

In the second experiment, people read forty factual statements of the kind you'd tend to look up with a search engine (eg, "an ostrich's eye is bigger than its brain") and then typed the statements into a computer. Half the participants were told the computer would save what they typed, and half were told that what they typed would be erased. Afterwards, the participants were asked to write down as many of the statements as they could remember. The experiment revealed that people who believed the information would be stored in the computer had a weaker memory of the information than those who assumed that the information would not be available in the computer. The researchers conclude: "Participants apparently did not make the effort to remember when they thought they could later look up the trivia statements they had read. Since search engines are continually available to us, we may often be in a state of not feeling we need to encode the information internally. When we need it, we will look it up."

The third experiment was a variation on the second, which again showed that people were less likely to remember a fact if they believed they would be able to find it on a computer and more likely to remember it if they believed it would not be available on a computer. The experiment further revealed that when people were asked whether a fact had been saved or erased, they displayed a better recall for the act of saving than erasing. "Thus," the researchers explain, "it appears that believing that one won’t have access to the information in the future enhances memory for the information itself, whereas believing the information was saved externally enhances memory for the fact that the information could be accessed, at least in general."

In the fourth experiment, people again read a series of factual statements and typed them into a computer. They were told that the statements would be stored in a specific folder with a generic name (eg, "facts" or "data"). They were then given ten minutes to write down as many statements as they could remember. Finally, they were asked to name the folder in which a particular statement was stored (eg, "What folder was the statement about the ostrich saved in?"). It was discovered that people were better able to remember the folder names than the facts themselves. "These results seem remarkable on the surface, given the memorable nature of the statements and the unmemorable nature of the folder names," the researchers write. The experiment provides "preliminary evidence that when people expect information to remain continuously available (such as we expect with Internet access), we are more likely to remember where to find it than we are to remember the details of the item."

Human beings, of course, have always had external, or "transactive," information stores to supplement their biological memory. These stores can reside in the brains of other people we know (if your friend John is an expert on sports, then you know you can use John's knowledge of sports facts to supplement your own memory) or in storage or media technologies such as maps and books and microfilm. But we've never had an "external memory" so capacious, so available and so easily searched as the web. If, as this study suggests, the way we form (or fail to form) memories is deeply influenced by the mere existence of external information stores, then we may be entering an era in history in which we will store fewer and fewer memories inside our own brains.

If a fact stored externally were the same as a memory of that fact stored in our mind, then the loss of internal memory wouldn't much matter. But external storage and biological memory are not the same thing. When we form, or "consolidate," a personal memory, we also form associations between that memory and other memories that are unique to ourselves and also indispensable to the development of deep, conceptual knowledge. The associations, moreover, continue to change with time, as we learn more and experience more. As Emerson understood, the essence of personal memory is not the discrete facts or experiences we store in our mind but "the cohesion" which ties all those facts and experiences together. What is the self but the unique pattern of that cohesion?

The researchers seem fairly sanguine about the results of their study. "We are becoming symbiotic with our computer tools," they conclude, "growing into interconnected systems that remember less by knowing information than by knowing where the information can be found." Although we don't yet understand the possible "disadvantages of being constantly 'wired,'" we have nevertheless "become dependent" on our gadgets. "We must remain plugged in to know what Google knows." But as memory shifts from the individual mind to the machine's shared database, what happens to that unique "cohesion" that is the self?

No comments: