PrepTest 120, Section 4, Question 10
Researcher: All defects in short-term memory are caused(60 more words not shown)
The reasoning in the researcher's(12 more words not shown)
- Adraws a general(10 more words not shown)
- Bpresumes, without giving(10 more words not shown)
- Cpresumes, without giving(11 more words not shown)
- Dfails to quantify(17 more words not shown)
- Etakes for granted(17 more words not shown)
Reading the argument
Why must every learning problem begin with short-term memory?
The researcher tells us that a defect in short-term memory comes from a malfunctioning hippocampus. Fine. But the conclusion concerns learning, defined here as accumulating new information in long-term memory. Those aren't interchangeable descriptions.
Maybe a child has trouble acquiring information in the first place. For example, difficulty reading could interfere with learning from a written lesson even if the child's short-term memory works normally. That's a possible gap in the argument, not a diagnosis of an actual child. We haven't been told that every learning deficit involves the particular memory problem the researcher described.
What we’re looking for
For the flaw question, look for that missing connection. The researcher has a rule about short-term memory defects and then applies it to all learning deficits. We need a reason to put every case in the conclusion under the rule in the premise.
Working the answers
- A
Where is the sample? The researcher doesn't report examining a small set of children and generalizing from those cases. The argument begins with a general claim about short-term memory and misapplies it to a broader category of problems.
- BCorrect
The researcher assumes that all learning deficits in children involve short-term memory. If they did, the initial rule would connect those deficits to a malfunctioning hippocampus. But that connection hasn't been established. A learning problem that doesn't involve short-term memory wouldn't be covered by the rule, leaving the conclusion unsupported.
- C
This goes from a disabled hippocampus to disabled short-term memory. The argument needs a different starting point: a child has a learning deficit. Even granting C's proposed connection wouldn't establish that this child has either a short-term memory defect or a disabled hippocampus. It misses the gap between learning deficits and short-term memory problems.
- D
We don't need an exact number of seconds to identify this mistake. Whether information stays in short-term memory for three moments or several more doesn't establish that every learning deficit involves a defect in that system.
- E
The researcher says nothing about whether adults' learning deficits have the same or different causes. The conclusion concerns children. Its problem is the unsupported link between all learning deficits and short-term memory, not an unstated comparison with adults.
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