reptiles have quiescent periods similar to mammalian sleep, and a decrease in electrical activity in the brain has been registered when the animals have been asleep. however, the eeg pattern in reptilian sleep differs from what is seen in mammals and other animals. in reptiles, sleep time increases following sleep deprivation, and stronger stimuli are needed to awaken the animals when they have been deprived of sleep as compared to when they have slept normally. this suggests that the sleep which follows deprivation is compensatorily deeper.