The terms "light sleep" and "deep sleep" are not very useful because

A) dreams occur during both REM and non-REM sleep.
B) brain activity increases in stages 1 and 3, and decreases in stages 2 and 4.
C) all stages of sleep are equally "deep."
D) paradoxical sleep is deep in some ways and light in others.

Light Sleep

A stage of sleep characterized by easy awakenings, decreased body movement, and lessened brain activity compared to deep sleep.

Paradoxical Sleep

Also known as REM (Rapid Eye Movement) sleep, it is characterized by vivid dreams and is considered a stage where the brain is highly active but the body's muscles are relaxed.

Brain Activity

The electrical and chemical processes occurring within the brain that enable thought, perception, and other neurological functions.