To prove to a roommate that she does dream, wake her up during stage 4 deep sleep and ask her what she's dreaming.

Question

Quizplus · Accepted Answer

It is not possible to wake someone up during stage 4 deep sleep as it is the deepest stage of non-REM sleep and waking someone up during this stage can cause disorientation and confusion. Additionally, dreaming is more common during REM sleep, which occurs after stage 4 deep sleep. Therefore, the method suggested in the question is not a reliable way to prove that someone dreams.

To Prove to a Roommate That She Does Dream, Wake