Rapid eye movement sleep resemblance to waking life), and incorporation of instinctual themes. Sometimes they include elements of the dreamer's recent experience taken directly from episodic memory. By one estimate, 80% of dreams occur during REM. Hobson and McCarley proposed that the PGO waves characteristic of “phasic” REM might supply the visual cortex and forebrain with electrical excitement which amplifies the hallucinatory aspects of dreaming. However, people woken up during sleep do not report significantly more bizarre dreams during phasic REMS, compared to tonic REMS. Another possible relationship between the two phenomena could be that the higher threshold for sensory interruption during REM sleep
Non-rapid eye movement sleep activity that takes place during NREM sleep is believed to be thought-like, whereas REM sleep includes hallucinatory and bizarre content. The mental activity that occurs in NREM and REM sleep is a result of two different generators, which also explains the difference in mental activity. In addition, there is a parasympathetic dominance during NREM. During the period of Non-REM sleep, the mindset of a person is more organized. The reported differences between the REM and NREM activity are believed to arise from differences in the memory stages that occur during the two types of sleep. It has been found through