Passage Three For years researchers thought that IQ, or fluid intelligence-the ability to solve new problems and reason well-could not be (1) . You had the smarts you were born with, period. No one believed that a few brain exercises, if done often enough, could boost (2) intelligence. A study published in Proceedings of the National Academies of Sciences shatters that dogm
a. Researchers ran participants through a (3) of training sessions with a computerized test that was (4) to become harder as the participants’ scores rose and (5) as their scores went down. The task involved observing two streams of stimuli, one heard (spoken consonants) and one seen (spatial locations). The demanding part (6) nothing when the two stimuli matched what had occurred two or even three steps (7) in the sequence. Each participant’s intelligence was (8) before taking the first test and after each training session. The researchers found that intelligence levels began (9) after 12 days and were markedly better after 17 days. (The researchers are planning longitudinal studies to measure long-term effects. ) "Our findings clearly show that intelligence is not immutable," says coinvestigator Susanne M. Jaeggi, a postdoctoral fellow in psychology at the University of Michigan. But, she adds, "you can’t expect to get (10) if you do such a training once or twice. You really have to stick to it for a fairly long amount of time."A. challengedD. designedG. improvingJ. measured M. provingB. changedE. earlierH. involved K. national N. seriesC. collectionF. easierI. later L. native O. smarter