Logical Reasoning

PT155 · S4 · Q3 Researcher: Newly formed neurons

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Researcher: Newly formed neurons can help to heal an injured brain but only if they develop into the type of neurons that are most common in the injured area.

Statements

conditional (only if)

Newly formed neurons Can't help aren't of the type that's → to heal an most common in the area injured brain

When it comes to the striatum, the most common type of neuron in the area is the midsized spiny neuron. But newly formed neurons there aren't of that type.

Evaluate

It seems like this is a classic Must Be True where they provide us with a conditional rule and then test our Contrapositive Logic abilities, in applying it to some fact.

For example, if we were told "Only blond firemen appeared in the calendar" and then told "Mario is a brunette", then we can infer that "Mario did not appear in the calendar".

Here, we were told that and then told .

Goal

Thus, we should be able to infer something like, .

If the researcher's statements are true, which one of the following must also be true?

Newly formed neurons sometimes develop
Out of Scope
Out of Scope: other than the striatum We have no idea if newly formed neurons do become midsized spiny neurons anywhere. It's possible they just never become midsized spiny neurons. This answer is trying to trap people into thinking that "the opposite of what we said applies in other contexts". Like if the passage said, "Jane is very polite at church", this answer would be baiting people into thinking, "so does that mean Jane is very impolite when she's not at church"? That's never a legal inference. We can affirm that "black lives matter" without implying that "non-black lives don't matter".
2% picked this
Newly formed neurons are commonly
Out of Scope: shortly after injury
We don't have any time-sensitive information about when newly formed neurons come on the scene. This is Must Be True, so we can't fabricate or speculate. We're just trying to derive truisms based on what we were told.
3% picked this
Midsized spiny neurons are not
Too Strong
Too Strong: any part Out of Scope: outside striatum Just like (A), we have no information whatsoever about what goes on outside the striatum. Just because midsized spiny are the most common within the striatum doesn't mean that the opposite is true outside the striatum. Just because Jane is polite at church doesn't mean she's impolite when she's not at church. She might just be polite!
3% picked this
Correct
In cases of injury to
Why this is right
As we predicted, by applying the conditional rule in the first sentence to the facts provided in the second sentence, we can derive that newly formed neurons won't help to heal an injury to the striatum. Newly formed neurons only help heal if they match the most common local type of neuron, and newly formed neurons in the striatum will never match the most common local type of neuron in the striatum.
Skill tested: Must be True · how this choice captures the argument's function is the move to repeat next time.
91% picked this
In most cases of brain
Too Strong: most cases
We only know about the case of the striatum. This information doesn't allow us to derive anything about other cases of brain injury.
2% picked this

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