<prompt> Altered presumption of real objects isIllusionDelusionHallucinationDelirium  <response>: A Illusion Hallucination-- caused by a substance; seeing andor hearing people, objects that are not there verbally responding to them. Delusion--false idea; misbeliefs example thinking one is a king or God or the president. Ideas of grandeur. Illusion-- seeing an object that isnt there; misconception of looking at something, but seeing it as something other than what it really is. E.g. a puff of smoke may look like a ghostly figure or a tree trunk with branches, may look like a person with arms extended. 