Brain

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Brain

by crackgmat007 » Fri Aug 07, 2009 9:04 am
For most people, the left half of the brain controls linguistic capabilities, but some people
have their language centers in the right half. When a language center of the brain is
damaged, for example by a stroke, linguistic capabilities are impaired in some way.
Therefore, people who have suffered a serious stroke on the left side of the brain without
suffering any such impairment must have their language centers in the right half.
Which of the following is an assumption on which the reasoning in the argument above
depends?
A. No part of a person’s brain that is damaged by a stroke ever recovers.
B. Impairment of linguistic capabilities does not occur in people who have not
suffered any damage to any language center of the brain.
C. Strokes tend to impair linguistic capabilities more severely than does any other
cause of damage to language centers in the brain.
D. If there are language centers on the left side of the brain, any serious stroke
affecting that side of the brain damages at least one of them.
E. It is impossible to determine which side of the brain contains a person’s language
centers if the person has not suffered damage to either side of the brain.

Support your answers with reasoning. OA - D
Source: — Critical Reasoning |

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Re: Brain

by shahdevine » Fri Aug 07, 2009 9:23 am
crackgmat007 wrote:For most people, the left half of the brain controls linguistic capabilities, but some people
have their language centers in the right half. When a language center of the brain is
damaged, for example by a stroke, linguistic capabilities are impaired in some way.
Therefore, people who have suffered a serious stroke on the left side of the brain without
suffering any such impairment must have their language centers in the right half.
Which of the following is an assumption on which the reasoning in the argument above
depends?
A. No part of a person’s brain that is damaged by a stroke ever recovers.
B. Impairment of linguistic capabilities does not occur in people who have not
suffered any damage to any language center of the brain.
C. Strokes tend to impair linguistic capabilities more severely than does any other
cause of damage to language centers in the brain.
D. If there are language centers on the left side of the brain, any serious stroke
affecting that side of the brain damages at least one of them.
E. It is impossible to determine which side of the brain contains a person’s language
centers if the person has not suffered damage to either side of the brain.

Support your answers with reasoning. OA - D
this is classic syllogism territory.

try to venn diagram this and you will see that in order for this argument (if we accept the premises to be true)to exist, the conclusion implies that a class (left side of the brain) at least one member..otherwise it commits an existential fallacy.

sorry if this doesn't help...maybe someone else can be more clear.

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by georgeung » Fri Aug 07, 2009 4:06 pm
I broke it down between C and D.

Please let me know if my examples are okay (I'm writing my notes verbatum, so it may seem pieced together):
Conclusion: Stroke on the left side without impairment means lang on right side.
Premise: Lang can be on right side or left side.
Assumption: Stroke on one side or the other will effect Language Centers.

A. Out of scope
B. Out of scope
C. Could
D. Could
E. According to the stimulus, one can determine where the language center is. Doesn't matter, out of scope.

Between C and D, I chose D.
After I read C, the word "more severely" popped up and I thought to myself, the assumption would not compare a stroke to anything else.

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by Spring2009 » Sat Aug 08, 2009 6:52 pm
I think A.
If they have language centers in the left half, but the left half of the brain can recover after a stroke, the linguistic capabilities
are still not impaired.
This really weakens the argument: the linguistic capabilities are not impared because the left half recovers, not because they have language centers in the right half.
Therefore, the author must assume this is not the case.

With D, the argument already states that "When a language center of the brain is damaged, for example by a stroke, linguistic capabilities are impaired in some way"
What D mentions merely restates the argument "if there are language centers on the left side of the brain, any serious stroke affecting that side of the brain damages at least one of them"
So D can't be the assumption.

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by life is a test » Sat Aug 08, 2009 9:05 pm
Spring2009 wrote:I think A.
If they have language centers in the left half, but the left half of the brain can recover after a stroke, the linguistic capabilities
are still not impaired.
This really weakens the argument: the linguistic capabilities are not impared because the left half recovers, not because they have language centers in the right half.
Therefore, the author must assume this is not the case.

With D, the argument already states that "When a language center of the brain is damaged, for example by a stroke, linguistic capabilities are impaired in some way"
What D mentions merely restates the argument "if there are language centers on the left side of the brain, any serious stroke affecting that side of the brain damages at least one of them"
So D can't be the assumption.
It is D because if you negate it then the conclusion falls apart --> if a stroke does not damage at least one of them then it means either the right or the left side of the brai is functioning, i.e. we can conclude that it is the right side as stated in the conclusion.

It is not A because it is irrelevant what happens after the impariment, i.e. we are not discussion whether or not it recovers. the argument here is concentrated around the fact that when the left side is damaged, it is the right side of the brain functioning.

georgeung - my reason for excluding C is because we are not concerned with the cause of the damage (stroke is only given as an example) - the cause of damage is outside the scope.

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by kris77 » Sun May 15, 2016 3:20 pm
n my opinion B is the most logical one.