Play, dreams, and simulation

Threat themes are clearly over-represented in dreams. Threat is, however, n ot the only theme with potential evolutionary significance. Even for hypnag ogic and hypnopompic hallucinations during sleep paralysis, for which threa t themes are far commoner than for ordinary dreaming, consistent non-threat themes have been reported. Revonsuo's simulation hypothesis represents an encouraging initiative to develop an evolutionary functional approach to dr eam-related experiences but it could be broadened to include evolutionarily , relevant themes beyond threat. It is also suggested that Revonsuo's evolu tionary re-interpretation of dreams might profitably be compared to argumen ts for, and models of, evolutionary functions of play.