Examkin

Question

Difficulty: MediumMust Be True / Most Strongly Supported

Cognitive neuropsychologists evaluating language recovery in a prospective clinical cohort established the following facts:

• Any patient exhibiting damage to the left inferior parietal lobule experiences severe phonological retrieval deficits.
• All patients with severe phonological retrieval deficits fail the rapid naming latency benchmark unless they receive structured multimodal speech therapy.
• No patient in the prospective clinical cohort who failed the rapid naming latency benchmark was able to maintain unassisted conversational fluency.
• Some patients in the cohort who received structured multimodal speech therapy nevertheless failed the rapid naming latency benchmark.
• Patient K is a participant in the prospective clinical cohort who maintained unassisted conversational fluency.

Based on the statements above, which of the following must be true? (Select all that apply)

  1. Patient K did not fail the rapid naming latency benchmark.Answer
  2. If Patient K exhibits damage to the left inferior parietal lobule, Patient K received structured multimodal speech therapy.Answer
  3. C
    Any patient in the prospective clinical cohort who received structured multimodal speech therapy maintained unassisted conversational fluency.
  4. D
    Every patient in the prospective clinical cohort who lacks damage to the left inferior parietal lobule avoids failing the rapid naming latency benchmark.
  5. E
    Patient K does not exhibit damage to the left inferior parietal lobule.

Answer

The statements establishing that Patient K did not fail the rapid naming latency benchmark and that Patient K received structured multimodal speech therapy if exhibiting damage to the left inferior parietal lobule must both be true.
The claim that Patient K did not fail the rapid naming latency benchmark is directly deduced via the contrapositive of the rule that benchmark failure precludes conversational fluency. The conditional claim regarding left inferior parietal lobule damage follows because such damage guarantees a phonological deficit, which would have caused benchmark failure in the absence of therapy; because Patient K did not fail, therapy must have occurred if the damage exists.

Step-by-Step Solution

1
Analyze the relationship between conversational fluency and the rapid naming benchmark for Patient K.
The stimulus states that no cohort member who failed the benchmark maintained fluency. Because Patient K maintained fluency, Patient K cannot have failed the benchmark.
Applying the contrapositive of the universal rule linking benchmark failure to loss of fluency directly establishes Patient K's benchmark outcome.
2
Evaluate the conditional chain starting from hypothetical damage to the left inferior parietal lobule for Patient K.
Parietal damage guarantees a phonological retrieval deficit. A deficit guarantees failing the benchmark unless therapy is received. Since Step 1 established that Patient K avoided failing the benchmark, having the deficit necessitates having received therapy.
Modus tollens on the conditional rule (Deficit and No Therapy entails Failure) combined with the proven non-failure yields Therapy when Deficit is present.
3
Evaluate the remaining claims against the stimulus to confirm invalid inferences.
Claims asserting universal success from therapy, universal success from the absence of parietal damage, or the complete absence of parietal damage in Patient K are unsupported.
The premises allow individuals receiving therapy to fail and do not restrict other causes of failure or prohibit Patient K from having damage if treated.

Key Concept

Conditional chaining, contraposition, and exception clauses in formal deductive logic
Estimated Time:1m 30s
Rate this question

Topics

Must Be True / Most Strongly Supported

More questions from this topic