Question

Nicole's sleep is being monitored in a sleep laboratory. If we compare the periods of deep sleep and the periods of REM sleep that occur during the night, we should find that:

a. both her REM periods and deep sleep periods will tend to get longer and longer over the course of the night.
b. the length of her sleep stages should not change during the course of the night.
c. her REM periods will get longer, while the deep sleep periods will get shorter and shallower.
d. her REM periods will tend to get shorter and shorter over the course of the night, while the deep sleep periods will get longer and longer.

Answer 1

The REM periods will tend to get shorter during the night, while the deep sleep periods will get longer.

Step-by-step explanation:

The correct answer is d. her REM periods will tend to get shorter and shorter over the course of the night, while the deep sleep periods will get longer and longer.

During a night of sleep, there are cycles of REM (rapid eye movement) sleep and non-REM sleep. Non-REM sleep is divided into three stages, with stage 3 being known as deep sleep. As the night progresses, the duration of REM sleep tends to decrease, while the duration of deep sleep tends to increase. This pattern is known as sleep architecture.

For example, at the beginning of the night, the first REM period may last around 10-20 minutes, while deep sleep periods may last 20-40 minutes. As the night continues, the REM periods become shorter, while the deep sleep periods become longer, with the final REM period lasting around 5-10 minutes and the final deep sleep period lasting around 60 minutes.