Logical reasoning PrepTest 135 · Section 2 · Question 9

Incorrect. First, what's important for the argument is that a large enough sample listened to the same category of take—conversation or music—before and after to draw a conclusion about the relative effects of them. Second, it's not necessary that all of the patients listened to the same category of tape. There could have been 2 other groups—one that listened to conversation before and music after; another that listened to music before and conversation after—and the study could still have reached a valid comparative conclusion about the two groups highlighted in the stimulus. Just because you learn about more groups doesn't mean you can't form a more limited conclusion.

Incorrect. The argument doesn't require people to naturally be at the same stress level before and after surgery because the argument isn't comparing the same person before and after surgery. If there are different stress levels before and after surgery, that would be equalized between people, and changes in relative stress levels based on the audiotapes could still be measured.

Correct. Argument or Facts:
Argument

Valid or Flawed:
Flawed

Question Type:
Strengthen with Necessary Premise

Stimulus Summary:
Study - Audiotapes were played for patients before and after surgery
Group 1 - Listened to conversations
Group 2 - Listened to music
Group 2 required less anesthesia and fewer painkillers than Group 1
Conclusion - Reducing stress reduces pain sensitivity

Answer Anticipation:
This argument starts with the conclusion before diving into the study that supports it. As with many arguments that are supported by a study, this argument has a causal conclusion—reducing stress reduces pain sensitivity.

Is that based on a correlation? It sure is—the group that listened to music required fewer painkillers and less anesthesia than the group that listened to conversation. So this argument commits a correlation/causation flaw.

But wait a second—correlation/causation flaws normally establish a correlation between the elements in the causal relationship featured in the conclusion. Those elements here are stress and pain sensitivity. While the study arguably looked at pain sensitivity (anesthesia and painkillers are related to pain sensitivity—especially anesthesia, since that's not under the patient's conscious control), it didn't necessarily look at stress levels. Instead, it assumes that those who listened to music were less stressed out than those listening to conversations. That could be true, but it could also be the case that Group 1 listened to a gentle voice reading pleasant poetry while Group 2 listened to death metal.

There is a correlation/causation flaw here, so we need to look for answers that address that (in a Strengthen with Necessary Premise question, that generally means the elimination of alternative causes), but we also need to look for answers that address this shift from listening to music to reducing stress.

Answer Explanation:
This answer addresses the term shift. In order to reach a conclusion that reducing stress reduces pain sensitivity, we need to know that the group that was said to have reduced pain sensitivity also had reduced stress. Instead, the argument establishes only that they listened to music. Therefore, the argument assumes that listening to music reduces stress, and if it doesn't, then there's no reason to believe that stress is related to pain sensitivity based on the results of the study.

Key Takeaway:
Studies tend to present correlations, so arguments with studies tend to feature correlation/causation flaws. This flaw, however, generally takes the form of the elements of the causal relationship showing up in the correlation—if the correlation is between other things, then there's a term shift on top of the correlation/causation flaw.

Incorrect. As long as the effects are related to stress while under the effects of these drugs, the argument can still work even if that's different from the normal response.

Incorrect. If anything, this argument weakens the relationship between stress and pain sensitivity by showing that it might be reversed.