|Title of host publication||Encyclopedia of Sleep and Dreams|
|Subtitle of host publication||The evolution, function, nature, and mysteries of slumber|
|Place of Publication||United States|
|Pages||272 - 275|
|Number of pages||4|
|Publication status||Published - 2012|
Neurobiolological theories of dreaming have remained divided since the first studies investigating brain mechanisms of dreaming. This is primarily due to the ongoing debate as to whether ponto?geniculo?occipital (PGO) waves are an underlying biological mechanism of dreaming. This debate remains unresolved because PGO activity can only be directly recorded in animals using indwelling electrodes, and dream reports are only obtainable from humans. However, there are now new, novel methods available that can be used to test phenomenological relationships between inferred PGO activity in humans and dream reporting on awakening. Such methods involve the presentation of sensory stimuli, at below waking threshold, in specific ways that have been shown to manipulate PGO activity in animals.