Brief Answer:
it can be occur at any stage,dreaming does not always mean deep sleep

Detailed Answer:
Hello,

Thanks for writing to us.

Dreams can occur in any stage of the sleep.
Sleep stages are divided in to NREM(Non Rapid Eye Movement ) and REM (Rapid Eye Movement)sleep.

In NREM sleep stage 3 and 4 are deepest sleep phase. Some of the dreams occur in these stages but dreams during these stages can not be remembered.So dreaming in this phase suggests deep sleep.

Most of the dreams occur in REM stage. Person can remember dreams of this stage as after this stage person awakes normally. It is phase with some of physiological changes in the body. It is not deep sleep.

Hope I have answered your query,
Regards,
Dr.Chintan Solanki.

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Brief Answer:
Msotly it is REM stage of sleep

Detailed Answer:
Hello,

Thanks for follow up.

Dreams can usually be remembered if a person is awakened while dreaming.

In normal sleep cycle REM is more occupied with dreams. As sleep hours progresses,each cycle of sleep occupies more amount of REM sleep.Person normally awakes during REM sleep and if any dream is going on at that time,he/she can remember with efforts.

NREM sleep is very deep sleep and person does not awake from it generally until dream is unusual and vivid.

There is considerable evidence that vivid, intense, or unusual dream content is more frequently remembered.It may occur during REM or even at NREM stage also.

At least 95% of all dreams are not remembered.

If you can remember your dream, in 80-90 % cases it is almost REM sleep stage.

Thanks & regards,
Dr.Chintan Solanki.

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