QUESTION TEXT: In an experiment, two groups of mice—one whose…
QUESTION TYPE: Weaken
CONCLUSION: Gingko might have aided memory only indirectly, by reducing stress.
REASONING: Mice fed gingko had better memory for navigating a maze. High stress can reduce memory, and gingko can reduce stress.
ANALYSIS: The LSAT depends on small distinctions. We know that lowering high stress can help memory. But that doesn’t mean that lowering regular levels of stress can help memory.
If the mice weren’t unusually stressed, then we have zero evidence that stress could have impaired their memories.
___________
- So? We don’t have any evidence that gingko becomes less helpful if you have more of it. Higher doses could still reduce stress.
- CORRECT. If this is true, then there’s little evidence for the conclusion. We only know that reducing high stress helps memory. If stress is at normal levels, it may not affect memory.
- So? “Some” is very weak. This answer doesn’t need to refer to gingko, so this answer has zero impact. (“some” could refer to chemical substances other than gingko”).
- So? We can know that something has an effect even if we don’t know why it has an effect.
If you picked this answer, know that you fell victim to a common myth. Science is about proving that things do happen. We also like to be able to prove why they happen, but knowing why something happens isn’t necessary for proving that something does happen. - This question is about memory, after the mice have learned to navigate. Initial learning time doesn’t matter.
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LSAT2019 says
Is the assumption that not having physiological signs of high stress means the rats are not highly stressed typical? I didn’t want to make that assumption so I initially ruled out B
FounderGraeme Blake says
Yes, and that’s a reasonable assumption. Certainly, the mice could in theory be stressed and not showing it. But that really isn’t normal amongst animals. Even we humans tend to be obviously stressed when we are stressed.
On a weaken question the answer doesn’t have to be rock solid perfect. It just has to weaken a reasonable amount. Suppose our conclusion is:
“The client is unhappy.”
This would weaken the statement: “The client looks happy and shows no signs of unhappiness”
Certainly, the client could be hiding their unhappiness. But the statement above reduces the odds they are unhappy, and that’s exactly what we’re looking for.
Note: This is an old comment but I wanted to clarify the point.
Manjot says
Can this question be cleared up a bit…it’s confusing.
TutorLucas (LSAT Hacks) says
Let’s break down the argument in the stimulus:
(1) The mice who were given ginkgo were more likely to remember how to navigate the maze than the mice who weren’t given ginkgo
(2) Studies show ginkgo reduces stress in mice and lowering very high stress is known to improve memory
Therefore, the ginkgo may not have directly improved their memory
This is a weaken question, so before you move on to the answer choices, it’s important to identify any obvious issues with the reasoning in the stimulus. The correct answer will very likely target one of these issues. One major issue with the argument in this stimulus is the fact that we only know that lowering “very high” stress improves memory. What if the mice are only experiencing an average or even low amount of stress? We don’t know if lowering that stress level still improves memory.
That’s why (B) is correct. If the mice are not experiencing higher than normal stress, then the reasoning of the argument is significantly weakened.