Judith is startled when her 6-year-old daughter, Laura, sleepwalks into the family room. It is most likely that Laura is experiencing the __________ stage of the sleep cycle.

A) REM
B) first
C) third
D) fourth

Fourth Stage

A phase or level in a sequence or process, the specific nature of which depends on the context it is used in (e.g., Erikson's stages of psychosocial development, the stages of labor).

Sleep Cycle

A period of sleep lasting about 90 minutes and including one or more stages of NREM sleep, followed by REM sleep.

REM Stage

A phase of sleep characterized by rapid eye movements, dreaming, and increased brain activity.