LSAT 158 | Section 4 | Logical Reasoning: Q14

LR Question 14 Explanation

QUESTION TEXT: Psychologist: Most people’s blood pressure rises when they talk…

QUESTION TYPE: Strengthen

CONCLUSION: Blood pressure rises when talking from psychological stress, not the physical act of talking.

REASONING: Blood pressure usually rises when speaking. But this rise is greater for introverts because speaking is more stressful for them.

ANALYSIS: To strengthen this, we need to show that it is stress of communication that elevates blood pressure, not just the physical processes required for the act of speech.

___________

1. We would not normally expect blood pressure medications to stop all fluctuations in blood pressure. You need higher blood pressure to stand, move and speak (even extroverts see a rise). Blood pressure medication lowers the average level of blood pressure but shouldn’t suppress all fluctuations. Lack of fluctuation = death.
    
   So….basically this answer says “Medication acts as we expect”. And what does that tell us? Absolutely nothing. The stimulus didn’t even mention medication!
2. This answer sets up a new relationship: between lower blood pressure and blood pressure rises due to stress. Whereas the argument was about introversion affecting blood pressure rises.
3. This answer choice only applies to introverts who do not have chronically high blood pressure: a narrow scope. We also don’t care about how people “sense” their rise in blood pressure. We only care about the rise itself. Sensing the rise doesn’t mean you can control it.
    
   Further, this answer makes a false comparison: it implies extroverts don’t sense rises, but doesn’t say it. Maybe extroverts also sense the rise! In which case there is no distinction at all. To make a proper comparison an answer needs to give information about both groups.
4. CORRECT. This answer might not jump out at you at first, but let’s think about it. How do deaf people communicate? Sign language, of course. So basically, sign language to a deaf person is the equivalent of talking to a non-deaf person. If these are equivalent, then it’s possible for deaf people to experience increased blood pressure when trying to communicate. If there is no increase when a deaf person is waving his hands for other reasons, that that shows that it’s communication (and the psychological stress) that’s raising the blood pressure, not just physically moving hands. This strengthens our conclusion.
5. We don’t know or care about relative likelihood. And “more likely” could be 0.1%; useless.

Recap: The question begins with “Psychologist: Most people’s blood pressure rises when they talk”. It is a Strengthen question. Learn more about LSAT Strengthen questions in our guide to LSAT Logical Reasoning question types.