PrepTest 106

[lcid:3520] Prep Test 106 LSAT — Logical Reasoning — S1 Logical reasoning

Question prompt

Further evidence of a Remaining source text redacted.
Why the credited answer is right

Credited answer: A

The notes below walk through why it fits the stem and how to eliminate the rest.

Argument or Facts

Argument

Valid or Flawed

Flawed

Question Type

Bizarro / Weaken Questions

Stimulus Summary

Mood and frontal lobe activity are correlated, so frontal lobe activity causes general disposition.

Answer Anticipation

Weaken questions feature a Correlation/Causation flaw more frequently than any other flaw, and that’s particularly true of Bizarro Weaken questions. The fact that this argument is explicit in stating that the evidence is a “correlation” between two things should have made it a lot easier to spot this flaw.
So the argument uses a correlation between mood and frontal lobe activity to prove that the frontal lobe activity affects general disposition. When we’re weakening an argument with a Correlation/Causation flaw, there are common answers to look for:
Identify an alternative cause Find counterexamples (cause without effect; effect without cause) Reverse causality
Note that in this Bizarro question, we eliminate any answer that falls into one of those categories!

Answer choices

  1. A
    Many drugs prescribed to Remaining source text redacted.
    Why choice A matches the stem
    If anything, this answer strengthens the argument. If the cure for depression works by increasing left lobe activity, that suggests there is a causal relationship between frontal lobe activity and general disposition. Since this answer strengthens the argument, it doesn’t weaken it, so it’s correct.
  2. B
    Excessive sleep, a typical Remaining source text redacted.
    Why choice B is not credited
    This answer suggests the causal relationship is reversed. Depression causes sleep, which causes suppressed lobe activity. In other words, general disposition causes changes to frontal lobe activity.
  3. C
    Frontal lobe activity is Remaining source text redacted.
    Why choice C is not credited
    This answer calls into question the relationship by establishing that one of the two elements fluctuates more than the other. If we fit this into our terminology, it shows counterexamples - general disposition changing without frontal lobe activity doing the same.
  4. D
    Earlier studies indicated that Remaining source text redacted.
    Why choice D is not credited
    This answer brings up an alternative cause of both correlated phenomena. In doing so, it weakens the causal relationship between those phenomena.
  5. E
    Social interaction of the Remaining source text redacted.
    Why choice E is not credited
    This answer is similar to (B) in that it suggests reversed causality. General disposition affects social interaction, which affects left lobe activity.

What this tests

Discussion