While biomedical models tend to use the terms complex visual hallucination, compound hallucination to denote apparitions, explaining their mediation by reference to aberrant neurophysiological activity in cerebral areas and/or the temporo-parieto-occipital junction, parapsychological models tend to combine such biomedical explanations with hypotheses related to a metaphysical origin of the perceived apparitions, such as the telepathic powers of dead or living agents.
