A Critical Review of Neural Net Theories of REM Sleep

Abstract

This paper discusses two recent speculations within the field of neural networks about the purpose of Rapid Eye Movement sleep, the time of sleep during which most vivid dreams occur.These theories are part of the information-processing view of REM sleep and are based on the finding that the mnemonic efficiency of neural networks is increased if the networks are programmed to periodically enter an altered state of functioning.One theory, that of Hopfield, Feinstein and Palmer /54/, emphasises the necessity for the network to enter this state throughout its life, whereas the other theory, that of Clark, Rafelski and Winston /19/, views the altered state as a preparation for learning by the newly formed network.Evidence is presented that the former algorithm is only relevant to systems which have orthogonal, separate memories; that the phenomenology of REM dreams is different from that predicted by both theories, and that the information-processing paradigm of REM sleep is widely contested.