Steven Pinker -- How the Mind Works - Hampshire High Italian ...

142 HOW THE MIND WORKSaround unglued. For example, a person not deliberately attending to aregion should not know whether it contains a red X and a green O or agreen X and a red O—the color and shape should float in separate planesuntil the conscious processor binds them together at a particular spot.Treisman found that that is what happens. When people are distractedfrom some colored letters, they can report the letters and they can reportthe colors, but they misreport which color went with which letter. Theseillusory combinations are a striking demonstration of the limits of unconsciousvisual computation, and they are not uncommon in everyday life.When words are glimpsed absent-mindedly or out of the corner of theeye, the letters sometimes rearrange themselves. One psychologist beganto study the phenomenon after he walked past a coffee machine andwondered why it claimed to be dispensing the World's Worst Coffee. Thesign, of course, really said "World's Best Coffee." One time I did a double-takewhen driving past a billboard advertising a brothel (actually theBrothers' Hotel). When flipping through a magazine I once caught sightof a headline about anti-semitic cameras (they were semi-antique).There are bottlenecks constricting the flow of information from insidethe person as well as from outside. When we try to retrieve a memory,the items drip into awareness one at a time, often with agonizing delaysif the information is old or uncommon. Ever since Plato invoked themetaphor of soft wax, psychologists have assumed that the neuralmedium must be inherently resistant to retaining information, fadingwith time unless the information is pounded in. But the brain can recordindelible memories, such as the content of shocking news and a few ofthe details of the time and place at which one hears it. So the neuralmedium itself is not necessarily to blame.The psychologist John Anderson has reverse-engineered humanmemory retrieval, and has shown that the limits of memory are not a byproductof a mushy storage medium. As programmers like to say, "It's nota bug, it's a feature." In an optimally designed information-retrieval system,an item should be recovered only when the relevance of the itemoutweighs the cost of retrieving it. Anyone who has used a computerizedlibrary retrieval system quickly comes to rue the avalanche of titlesspilling across the screen. A human expert, despite our allegedly feeblepowers of retrieval, vastly outperforms any computer in locating a pieceof information from its content. When I need to find articles on ia topicin an unfamiliar field, I don't use the library computer; I send email to apal in the field.