PrepTest 151, Section 4, Question 9
The brain area that enables one to distinguish(42 more words not shown)
Which one of the following(8 more words not shown)
- AThe argument presumes,(27 more words not shown)
- BThe argument fails(26 more words not shown)
- CThe argument draws(17 more words not shown)
- DThe argument fails(46 more words not shown)
- EThe argument presumes,(12 more words not shown)
Reading the argument
Did playing music enlarge that brain area, or did that brain area help someone become a musician?
The comparison tells us that highly skilled musicians tend to have a larger area involved in distinguishing piano sounds. It doesn't tell us which came first. Perhaps people who already have a larger area find music easier, choose to learn an instrument, or stick with it long enough to become skilled.
What we’re looking for
The author picks the other explanation: practicing and playing changed their brains. That might be true, but the comparison alone doesn't settle it. For the flaw, I'd look for the possibility that the brain difference helped produce the musical skill, rather than the skill producing the brain difference.
Working the answers
- A
The evidence concerns highly skilled musicians, not just pianists. The piano appears in the description of the sounds the brain area helps distinguish. That doesn't make every person being studied a piano player. A invents a shift from pianists to other musicians that the argument doesn't make.
- BCorrect
Perhaps the size of this area helps people become highly skilled musicians. They might be drawn to music or more likely to keep practicing because they already find it easier to distinguish sounds. Then we could find the stated brain difference even without playing music having created it. The argument needs to address that direction of explanation before claiming the comparison shows that practice alters brain structure.
- C
The conclusion doesn't generalize to every brain area or every kind of human activity. A change in this particular area would be a change in brain structure, if playing music actually caused it. The unsupported step concerns that causal explanation, rather than a leap from this area to a broad range of unrelated phenomena.
- D
Comparing people who listen to music with people who play it still wouldn't tell us why the players have a larger area. It might have grown through playing, or it might have helped them become players in the first place. D leaves those explanations unresolved. Merely naming another comparison the argument doesn't address doesn't identify the flaw in the one it makes.
- E
The comparison isn't between highly skilled musicians and less-skilled musicians. It is between highly skilled musicians and people who have rarely, if ever, played an instrument. We don't need a claim that the most skilled musicians practice more than every other musician to make that comparison. E introduces a different contrast and misses the question of what caused the brain difference.
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