Final answer:
REM sleep is linked to the development and preservation of neural pathways in the brain, featuring brain activity similar to wakefulness and associated with dreaming.
Step-by-step explanation:
One theory suggests that the brain activity associated with REM sleep is helpful for developing and preserving neural pathways in the brain. REM sleep is marked by rapid eye movements and a state of sleep where the brain waves are very similar to those observed when awake. This period of sleep is also when most dreaming occurs. It is associated with paralysis of muscle systems in the body, except those necessary for circulation and respiration, meaning no voluntary muscle movement happens during REM sleep. Both NREM and REM sleep have been implicated in various aspects of learning and memory, with dreams potentially representing important life events or a state of protoconsciousness that aids a person during wakefulness.