Sleep research has demonstrated that

Answer choices

1. A

   Weakens4% picked this

   Test subjects who are chronically deprived of non-REM sleep also become irritable

   This suggests an alternate explanation for the correlation — it's not being deprived of REM sleep that is making people irritable. It's just being deprived of sleep, period. Apparently, this same thing happens when you're denied non-REM sleep too, so sleep is the causal difference-maker, not REM sleep.

   4%
2. B

   No Impact1% picked this

   Chronically having bad dreams can cause stress, but so can chronically having pleasant

   This is very weakly worded, since it's just saying that "X can lead to Y". It's also discussing an uncommon case (chronically, i.e. constantly, having bad dreams or exciting dreams). It also seems to be irrelevant to the Curious Fact, since we're trying to figure out why people who are chronically deprived of REM sleep (and thus deprived of any dreams) are irritable. Since this answer is about people who have dreams, it's not about the people in our curious fact.

   1%
3. C

   Weakens, if anything10% picked this

   During times of increased stress, one’s REM sleep is disturbed in a way that prevents

   This answer would complicate the author's storyline. She is thinking that when waking life is stressing us, REM sleep will relieve that stress and keep us from being irritable. But this answer is saying that when waking life is stressing us, it will actually prevent us from even having REM sleep.

   10%
4. D

   No Impact: reporting dreams0% picked this

   Only some people awakened during REM sleep can report the dreams they were having just

   It makes zero difference to this argument whether people can / can't remember their dreams. We only care about why they're irritable and whether REM sleep-deprivation is the cause.

   0%
5. E

   Correct86% picked this

   Other factors being equal, people who normally have shorter periods of REM sleep tend to

   Why this is right

   This adds some plausibility to the conclusion and addresses the new concept, "stress", that only appeared in the conclusion. If REM relieves stress, then the author would expect that people who don't experience REM will have more stress buildup. This answer corroborates that expectation. It doesn't fully prove the author is right, but it adds some plausibility to the story she's weaving.

   Skill tested: Strengthen · how this choice captures the argument's function is the move to repeat next time.

   86%