Do all mammals dream?
The Journal of comparative neurology December 1, 2020 Paul R Manger, Jerome M Siegel 21 citations
Dreams occur during human sleep, especially REM sleep, and similar physiological states exist in mammals, raising the question of whether animals experience sleep mentation. Advances in understanding sleep-stage anatomy and physiology allow a better assessment of dream mentation in nonhuman mammals. If dream mentation occurs only during REM sleep, monotremes, cetaceans, and otariid seals at sea likely lack this potential; atypical REM sleep in African elephants and Arabian oryx may alter their potential. If dream mentation occurs during both non-REM and REM sleep, all mammals could experience it, though non-REM mentation may differ in species with atypical sleep, such as aquatic mammals with unihemispheric sleep.