In the study, the researchers sought to understand how the brain uses this following information to adjust our perception of what we initially heard. To do this, they conducted a series of experiments in which the subjects listened to isolated syllables and similarly sounding words. Their results produced three primary findings: The brain’s primary auditory cortex (听觉皮层) is sensitive to how ambiguous a speech sound is at just 50 milliseconds after the sound’s appearance. The brain “replays” previous speech sounds while interpreting the following ones, suggesting re-evaluation as the rest of the word unfolds. The brain makes commitments to its “best guess” of how to interpret the signal after about half a second.

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A new study suggests that science role-playing may help tighten the gender gap in science, technology, engineering, and math(STEM)education and careers for women simply by improving their identity as scientists.

Frustrated by the gender gap in STEM, in which some fields employ at least three times more men than women, Cornell graduate student Reut Shachnai wanted to do something about it. Reut said the idea to help foster young girls’ interest in science came to her during a lecture in a class she was taking on Psychology of Imagination.

Reut designed an experiment to test if assuming the role of a successful scientist would improve girls’ persistence in a “sink or float” science game. The game itself was simple yet challenging: a computer screen projected a slide with an object in the center above a pool of water. Kids then had to predict whether the object would sink or float.

She studied 240 four -to -seven -year -olds, because this is around the time kids first develop their sense of identity and capabilities. They were divided into two groups. Children in the “story” group learned about the successes and struggles of a gender -matched scientist before playing the game. Boys heard about Isaac Newton and girls were told about Marie Curie. Children in the “pretend” group were told to assume the identity of the scientist they just learned about.

All kids played at least one round of the game. No matter what group they were in, girls got the answers right just as often as boys -nearly 70% of the time. Boys, however, didn’t really benefit from the stories or make-believe. Besides, girls pretending to be Dr. Marie persisted twice as long at the sink-or-float game, playing just as much as the boys did.

Reut’s teacher Tamar Kushnir said, “Rather than merely hearing about role models, children may benefit from actively performing the type of actions they see role models perform. In other words, taking a few steps in the role model’s shoes, instead of merely observing her walk.”

On March 7, I907, the English statistician Francis Galton published a paper which illustrated what has come to be known as the “wisdom of crowds” effect. The experiment of estimation he conducted showed that in some cases, the average of a large number of independent estimates could be quite accurate.

This effect capitalizes on the fact that when people make errors, those errors aren’t always the same. Some people will tend to overestimate, and some to underestimate. When enough of these errors are averaged together, they cancel each other out, resulting in a more accurate estimate. If people are similar and tend to make the same errors, then their errors won’t cancel each other out. In more technical terms, the wisdom of crowds requires that people’s estimates be independent. If for whatever reasons, people’s errors become correlated or dependent, the accuracy of the estimate will go down.

But a new study led by Joaquin Navajas offered an interesting twist (转折) on this classic phenomenon. The key finding of the study was that when crowds were further divided into smaller groups that were allowed to have a discussion, the averages from these groups were more accurate than those from an equal number of independent individuals. For instance, the average obtained from the estimates of four discussion groups of five was significantly more accurate than the average obtained from 20 independent individuals.

In a follow-up study with I00 university students, the researchers tried to get a better sense of what the group members actually did in their discussion. Did they tend to go with those most confident about their estimates? Did they follow those least willing to change their minds? This happened some of the time, but it wasn’t the dominant response. Most frequently, the groups reported that they “shared arguments and reasoned together”. Somehow, these arguments and reasoning resulted in a global reduction in error. Although the studies led by Navajas have limitations and many questions remain, the potential implications for group discussion and decision-making are enormous.