PrepTest 106, Section 2, Question 8
The symptoms of mental disorders are behavioral, cognitive,(49 more words not shown)
The argument depends on assuming(5 more words not shown)
- ATreatment by psychotherapy(15 more words not shown)
- BTreatment with medication(14 more words not shown)
- CMost mental disorders(10 more words not shown)
- DMedication is always(11 more words not shown)
- ETreatment with psychotherapy(13 more words not shown)
Reading the argument
Why would a chemical cause automatically require medication? The passage tells us what causes some patients' disorders, but it hasn't yet shown that only one kind of treatment could help them.
Could psychotherapy relieve the symptoms even if the imbalance remained? That's one possibility the conclusion seems to rule out without explanation. The author moves from a claim about the source of a problem to a claim about the only effective response. Identifying the source doesn't by itself eliminate every other route to improvement.
What we’re looking for
For a required-assumption question, I'd look for something excluding another effective treatment. My initial concern is that a treatment might work on the symptoms without correcting the cause. The argument needs to close off alternatives.
Working the answers
- ACorrect
This identifies another route we need to consider: psychotherapy might reduce or correct the chemical imbalance itself. If it could, medication would not be the only way to produce the very correction the author relies on.
That is a little different from the symptom-relief possibility we first considered. The answer goes directly to the chemical cause. The author needs to deny that psychotherapy can effectively address it; otherwise, the claim that these patients can be effectively treated only with medication loses its basis.
A doesn't establish that medication alone is effective in every case, or eliminate every imaginable treatment. It states one exclusion the argument needs, which is enough for a required assumption.
- B
Faster isn't the same as uniquely effective. A slower treatment could still work, and the conclusion concerns whether any treatment besides medication is effective, not how soon results arrive. Medication needn't always be faster for the argument's claim about this group to hold.
- C
The proportion of disorders caused by chemical imbalances doesn't settle how to treat patients in that group. They could be a small minority or a large majority, and the question would remain whether medication is their only effective treatment. A claim about most disorders is unnecessary.
- D
This compares treatments for all patients with mental disorders. The conclusion is limited to the patients whose disorders result from the specified chemical imbalances. Psychotherapy might work better for patients outside that group without undermining the author's conclusion about those inside it. This broader claim is not required.
- E
The argument doesn't need to limit everything psychotherapy can do for every mental disorder to symptom reduction. It could address causes in other kinds of cases while failing to treat the chemical-imbalance cases effectively. Also, merely distinguishing symptom relief from other effects doesn't itself establish which relief counts as effective treatment. E is not the precise exclusion the argument depends on.
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