Nathan was a psychologist in the 1930s. Which of the following would best represent his understanding of what happened inside the brain during sleep?

A) Humans pass through five distinct stages of sleep.
B) Humans, unlike animals, experience REM sleep, but both experience non-REM sleep.
C) Neurons fire and create the biological underpinnings of dreams and nightmares as we sleep.
D) Nothing interesting happens as humans sleep through the night.

Answer: D