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
Eye movement can make the photoreceptors or the ganglion cells become unresponsive; on the other hand a changing stimulus will not. Therefore, the random eye movement constantly changes the stimuli that fall on the photoreceptors and the ganglion cells, making the image more clear. Saccades are the rapid movement of eyes that is used while scanning a visual scene. In our subjective impression, the eyes do not move smoothly across the printed page during reading. Instead, our eyes make short and rapid movements called "saccades". During each "saccade" the eyes move as fast as they can and the speed cannot be consciously