In role-playing games, metagaming is a term often used to describe players' use of assumed characteristics of the game.
Various factors can contribute to sleep terrors, such as: 1  Sleep deprivation and extreme tiredness. 2  Stress. 3  Fever (in children). 4  Sleeping in unfamiliar surroundings. 5  Lights or noise. 6  An overfull bladder.
There can be a number of psychological triggers that cause nightmares in adults. For example, anxiety and depression can cause adult nightmares. Post-traumatic stress disorder (PTSD) also commonly causes people to experience chronic, recurrent nightmares. Nightmares in adults can be caused by certain sleep disorders. These include sleep apnea and restless legs syndrome. If no other cause can be determined, chronic nightmares may be a distinct sleep disorder. People who have relatives with nightmare disorder may be more likely to have the condition themselves.