#10 - Researcher: All defects in short-term memory are

[Administrator]

Complete Question Explanation

Flaw in the Reasoning-CE. The correct answer choice is (B)

To understand the flawed pattern of reasoning in a given stimulus, it is crucial to analyze the logical structure of its argument:

• Premise (1): Defects in short-term memory are caused by malfunctions of the hippocampus;
  
  Premise (2): Information stored in short-term memory is either stored in long-term memory or forgotten;
  
  Premise (3): Learning is the accumulation of new information in long-term memory;
  
  Conclusion: A malfunction of the hippocampus must be responsible for a child’s learning deficit
  
  Cause Effect
  Malfunction of hippocampus Learning deficit

If learning is the accumulation of new information in long-term memory, a learning deficit essentially describes a defect in long-term memory. For the conclusion to be true, it must be assumed that any defect in long-term memory is also a defect in short-term memory, which is caused by malfunctions of the hippocampus. In other words, the conclusion presumes without warrant that all learning deficits (i.e. all defects in long-term memory) must involve defects in short-term memory as well. Answer choice (B) is therefore correct.

Answer choice (A): The sample of learning deficits is not too small; it is the cause of these deficits that is unreasonably restricted to problems involving short-term memory. This answer choice is incorrect.

Answer choice (B): This is the correct answer choice. See discussion above.

Answer choice (C): The fact that defects in short-term memory are always caused by malfunctions of the hippocampus does not presume that short-term memory is disabled whenever the hippocampus is disabled. This is a reversal of the first sentence of the argument.

Answer choice (D): Quantifying the precise length of time during which the mind holds a piece of information in short-term memory is unnecessary and irrelevant to the conclusion of the argument. There is no reason to suspect that a more precise length of time than the “few moments” offered in the stimulus is necessary to establish the conclusion. This answer choice is incorrect.

Answer choice (E): Since the subject of learning deficits in adults was never mentioned in the stimulus, their comparison to learning deficits in children is inconsequential and irrelevant to the conclusion.

[mmathew]

Hi Powerscore,

I am confused as to the way that you diagrammed the first premise. It is a causal indicator "Caused by". So isnt the malfunctioning of the hippocampus the cause of the Short term memory defects?

I got the question right, but I dont see how choice C is a reversal. The statement is a conditional but talking about the disability of the two components.

Hippocampus disabled--> short term memory is disabled

[Adam Tyson]

Thanks for the question, mmathew! I think answer C is better described not as a reversal of the first sentence, since a true reversal would be something along the lines of "when short term memory is defective it causes defects in the hippocampus", but rather as an extreme claim that isn't supported by the first sentence. Just because a malfunction in the hippocampus causes a defect in short term memory, that does not mean that completely turning off the hippocampus (which is how I interpret "disabling" - shutting it down) causes short term memory to shut down. Perhaps a disabled hippocampus is not a "malfunctioning" hippocampus? Even if disabling it is interpreted to mean it is malfunctioning, then it still only would have to cause a defect in short term memory, which may not be as extreme as completely disabling short term memory. The author never commits himself to such an extreme position, so that is not his flaw. Instead, his flaw is in assuming that because short term memory is involved in learning, that a defect in short term memory (caused by the hippocampus) is the ONLY thing that can cause problems with learning.

Sorry for any confusion caused by our explanation! Your understanding of the argument appears to me to be correct!