Q24

[bermudask8er7]

Can you explain why D is correct and B is incorrect? Thanks.

[ManhattanPrepLSAT1]

Understandably difficult. Don't worry you're not alone. In almost every class where this question comes up in a lesson or a practice test, it always generates a discussion.

The reason why answer choice (B) is incorrect though is that it is too broad. The scope is wrong. It's not that the answer choice is out of scope, but rather that its scope is too broad. We're looking for answer an choice that identifies the specific neurons in the passage. Unfortunately, there might be many other neurons that also respond to drug treatment. So the neurons of answer choice (B) aren't necessarily the ones discussed in the passage.

Answer choice (D) is not great, but it's a bit more defined. It says that the neurons influence particular brain functions. The use of the word particular is a reference to the functions being discussed in the passage, so answer choice (D) is a reference to the neurons in the passage as well.

Not easy to see, and I'm open for debate on this one if you see it differently!

[geverett]

Matt,
I would love some more in depth analysis of this question. Maybe even a good breakdown of the passage as a whole would help shed some light on it if you would be so kind. This passage has been the source of much debate in some of the groups that have been meeting from the october thread.

Another question I have is could not the same thing be said for answer choice D? Meaning could there not be other neurons that also influence brain functions?

[leroyjenkins]

Bump to this reply.

The explanation offered seems inadequate. It seems from the preceding text that defined categories refers specifically to "the possibility of highly selective treatment of brain disorders."

Even more direct, the text preceding "defined categories" in the very sentence where that phrase appears refers to the possibility of designing "drugs targeted to specific receptors." Immediately following the phrase defined categories is "neurons that will selectively impede or enhance these effects," where effects refer to the effects of medicine.

Given that "defined categories of neurons" is sandwhiched between text which refers to drugs and their effects, how can the best answer not be B? Doesn't brain function seem a step removed from this, as the drug treatment is what would affect these particular neurons, which subsequently influences brain function (even if the drugs also affects other neurons)? Keep in mind that no neurons operate in a vacuum, and that just as other neurons may respond to drug treatment, other neurons (not just the defined categories) may influence the particular brain function referred to in D.

Can you please help resolve this issue?

Thanks.

[uhdang]

Hi, I'd like to share my thoughts on this matter, for I was really confused with the answer choice B) and D).

Because referring to what was before the line 55-56 seemed to be more related to "drug's impact and its effectiveness", B) seemed appropriate, but it felt a bit awkward.

After tedious attempts to look for a specific line reference to the support of either B) or D), I decided that it's better to look for the author's intention in using this term from the flow of the writing.

In regarding the flow, the last paragraph talks about potential "selective" treatment with newly gained knowledge of varying qualities of receptors.

Thus, when using the phrase "defined categories of neurons", it is important to indicate those neurons act differently in terms of functions. So that "impeding and enhancing" through drugs could result in "selective treatment" that the author points out as implications.

For B), nowhere in this paragraph the author distinguishes there are neurons that does respond or does not respond to drug treatment. "defined categories" does not indicate "respond-ability" of neurons.

While I couldn't point out exactly how to approach or categorize this solution, the best way to describe how this incorrect answer has been dealt with is the "scope." (like Matt mentioned earlier)

[AyakiK696]

Still very confused about this question, even after reading all the explanations..... I, too, was caught up between B and D, and went with B since it seemed to go with the general gist of what the sentence indicated to be true, i.e. that the neurons would respond to the drugs. What is meant by the "scope" of the question being too broad in this instance? Could someone please clarify this? Thank you!

[ohthatpatrick]

Once we've figured out how all the neurotransmitters work, we can design drugs to specifically target certain neurons, in order to achieve some specific effect we want the drug to do.

Each drug will target receptors on a "defined category of neurons" in order to impede or enhance them.

One category might be "the category of neurons having to do with telling your brain whether you're hungry".

They could design a drug meant to impede this effect
(if you're trying to lose weight .... your brain won't know you're hungry as much, so you'll eat less)
or enhance this effect
(if you're appetite is gone from being on chemotherapy, for example .... your brain will have an easier time thinking it's hungry).

The idea with (B) is too nonspecific ... drug makers will design drugs that target parts of the body that respond to drug treatment?

That's a tautology (a self-defining truth). Of course drug makers design drugs that target parts of the body that respond to drug treatment. A drug that targeted something that doesn't respond to drug treatment wouldn't work.

The idea with (D) is appropriately specific ... drug makers will design drugs that target particular brain functions.

THAT'S how they can separately target different things like mood disorders, tissue damage, Alzheimer's, etc.

(B) is appealing because it's definitely TRUE that these neurons would respond to drug treatment, but it's such a boring truth that it's almost empty.

(D) is better because it ties in better to the idea in 52-60 that by solving the mystery of the "precise effect on behavior of every variety of each neurotransmitter-gated ion channel" we can make customized drugs.