Dreaming is a loss of perception and orientation. Dreaming allows a freedom to create a false scenario effortlessly. We dream in order to forget.
When we dream we don't wake up, can't see our surroundings, nor feel heat. Perception, instinct, action, sensation, bad judgment, awareness, orientation, and recent memory are all impaired while dreaming.
There is no self-awareness to time, place or persons. All external sensory signals are also blocked. Norephenerine and seratonin are reduced during dreaming.
Our muscles and sensory nerves become paralyzed. Dopamine triggers the normal psychosis of dreaming. It is produced by midbrain neurons (in front of the medulla and pons).
It interacts with seratonin, norepinepherine and acetylcholine. They all release cyclic AMP that energizes neurons. Drugs block dopamine and raise seratonin and norephinephrine levels. Antidepressant drugs block acetylcholine.
This can correct a sleep problem for a short time but in the long term drugs result in light and poor sleep. The block to the RE system is gone and the thalamus is reactivated.
Visual, emotional, and movement centers are also reactivated. However real behavior remains blocked. Dreams often cannot be recalled. The memory system is driven into a playback mode and the brain can't store the memory into short-term memory.
To remember dreams requires a second message system where messages from the cell membrane go the cell's nucleus. Lack of sleep makes dreaming more intense.
If we are to dream, the temporal lobe (seat of emotions) must be turned on. Emotions determine the content of dreams. There is no dreaming possible when the parietal lobe is not functioning.