单选题
The Advantages of Being Helpless
A. At every stage of early development, human babies lag behind infants from other species. A kitten can walk slowly across a room within moments of birth and catch its first mouse within weeks, while its human counterpart takes months to make her first step, and years to learn even simple tasks, such as how to tie a shoelace or skip a rope. Yet, in the cognitive race, human babies turn out to be much like the
tortoise (乌龟) in Aesop's fable: emerging triumphant after a slow and steady climb to the finish.
B. Yet, this victory seems puzzling. In the fable, the tortoise wins the race because the hare takes a nap. But, if anything, human infants nap even more than kittens! And unlike the noble tortoise, babies are helpless, and more to the point, hopeless. They could not learn the basic skills necessary to their independent survival. How do human babies manage to turn things around in the end?
C. In a recent article in
Current Directions in Psychological Science, Sharon Thompson-Schill, Michael Ramscarand Evangelia Chrysikou make the case that this very helplessness is what allows human babies to advance far beyond other animals. They propose that our delayed
cortical development (皮质发育) is precisely what enables us to acquire the cultural building blocks, such as language, that make up the foundations of human achievement. In the same way, they suggest, our ability to learn language comes at the price of an extended period of cognitive immaturity.
D. This claim hinges on a peculiar and unique feature of our cognitive architecture: the stunningly slow development of the
prefrontal cortex (前额皮质), or PFC. The PFC is often referred to as the 'control' center of the brain. One of its main functions is of selectively filtering information from the senses, allowing us to attend to specific actions, goals, or tasks. For this reason, cognitive 'control' tasks are thought to be one of the best assessors of PFC function and maturity.
E. The
Stroop task (斯特鲁普任务) serves as a simple assessor of PFC function in adults. The task involves naming the ink color of a contrasting color word: for example, you might see the word 'red' written in green ink, in which case you have to say 'green'. Tricky or not, healthy adults can successfully complete the task with only minor hesitation. Children, with their immature PFC's, are a different story. Typically, the younger children are, the worse they are at solving Stroop-like tasks, and under the age of four, they outright fail them. While young children are sensitive, apt learners, and often appear to fully understand what is being asked of them, they are unable to mediate the conflicting demands present in these sorts of tasks, and thus fail them, time and time again. Three-year olds simply cannot direct how they attend to or respond to the world.
F. Thompson-Schill and her colleagues suggest that this inability to direct attention has important consequences when it comes to learning about uncertain events. For example, imagine you are playing a guessing game: You have to choose one of two options, either A or B, one of which leads to a prize, and the other does not. After a few rounds, you notice that about 3/4 of the time the prize is at A, and the rest of the time it is at B, so you decide to guess 'A' 75 percent of the time and 'B' 25 percent of the time. This is called probability matching, and it is the response pattern most adults tend to adopt in these circumstances. However, if the goal is to win the most prizes, it is not the best strategy. In fact, to maximize the number of correct predictions, you should always pick the more frequent outcome (or, in this case, always pick 'A').
G. Interestingly, if you were playing this kind of guessing game with a kid, you would see that he would employ the maximization strategy almost immediately because they lack the cognitive flexibility that would allow them to alternate between A and B. Fortunately for them, in this guessing game scenario, maximization is the right choice.
H. While it may not be immediately obvious what this has to do with language learning, it just might have everything to do with it, because language relies on conventions. In order for language to work, speakers and listeners have to have the same idea about what things mean, and they have to use words in similar ways. This is where children come in. Young children, as it turns out, act like finely tuned
antennas (天线), picking up the dominant frequency in their surroundings and ignoring the static. Because of this—because children tend to pick up on what is common and consistent, while ignoring what is variable and unreliable—they end up homing in on and reproducing only the most frequent patterns in what they hear. In doing so they fail to learn many of the subtleties and characteristics present in adult speech (they will come to learn or invent those later). However, this one-track learning style means that what they do learn is highly conventionalized.
I. The superiority of children's convention learning has been revealed in a series of ingenious studies by psychologists Carla Hudson-Kam and Elissa Newport, who tested how children and adults react to variable and inconsistent input when learning an artificial language. Strikingly, Hudson—Kam and Newport found that while children tended to ignore 'noise' in the input, systematizing any variations they were exposed to, adults did just the opposite, and reproduced the variability they encountered. Children's inability to filter their learning allows them to impose order on variable, inconsistent input, and this appears to play a crucial part in the establishment of stable linguistic norms. Studies of deaf children have shown that even when parental attempt sat sign are error-prone and inconsistent, children still extract the conventions of a standard sign language from them. Indeed, the variable patterns produced by parents who learn sign language offers insight into what might happen if children did not maximize in learning: language, as a system, would become less conventional. What words meant and the patterns in which they were used would become more unstable, and all languages would begin to resemble
pidgins (混杂语言).
J. While no language is completely stable, there is a balance to be struck between an individual's expressivity and the conventions that underpin it, and children clearly play an important role in maintaining this balance. Children may learn the established characteristics of their community, but they do so only because these forms are stable in their input. They are unlikely to adopt highly unusual or characteristic forms or sequences that they've heard only rarely, and when they themselves make errors, they are similarly unlikely to incorporate these errors into their language use over the long run.
K. Individual societies are built upon these kinds of cultural and linguistic conventions, and a vast array of them. As social animals, human babies must somehow master not just 'culture and language,' but the specifics of their culture, and their language. Explaining how babies manage to learn all of this information is a formidable task. The research reviewed here reveals one advantage that nature may have conferred on human infants: when it comes to conventionlearning, children' sinability to think unconventionallyor flexibly may be of huge benefit. Indeed, a number of neurological studies suggest that children who often exhibit marked language delays and characteristic language development experience a massive overgrowth of the prefrontal cortex over the first two years of life.