A theory of threat simulation theory was proposed by Antti Revonsuo and states the biological function of dreaming is to simulate threatening events and then rehearse threatening avoidance behaviors. However, this theory has had a mixed reception. Zadra et el. found in a study on this theory that 66% of recurrent dreams contained at least one threat.
Antonio de Pereda, Public domain, via Wikimedia Commons
For the most part, these threats involved danger and were aimed at the dreamer themselves. In contrast however, they also found that less than 15% of recurrent dreams involved realistic situations that could prove critical to one's survival. They also found that the dreamer usually did not succeed at fleeing the threat. These provide mixed support for the theory originally proposed by Revonsuo.
Difficulties with house maintenance
Teeth falling out
Discovering new rooms in a house
Losing control of a vehicle
Being unable to find a toilet
Having the ability to fly
Being held down or otherwise unable to move
Nakedness in a public place
Being held back in school or failing a test or exam you didn't know about
Losing the ability to speak
Escaping or being caught in a tornado or storm
Drowning, or otherwise not being able to breathe
Finding lost items
Unable to turn on the lights in one's house
Being with a significant other
Missing a bus, taxi, plane or train, and possibly attempting to chase it
Having to return to an old school, college, and/or workplace, due to an unfinished assignment or other unresolved issues
Being chased by an animal or murderer
One's house catching on fire
Falling from a very high place
Nuclear attack
Reliving traumatic experiences
Seeing the same person and/or persons
Certain persons promising to protect one especially from danger
Unable to flush a toilet in one's house
Anxiety over a traumatic experience
Fear of missing an event or appointment
Missing an event or appointment
People, animals, and/or objects disappearing in clear view
Visiting dead or lost relatives and/or friends
Visiting a former crush, friend, and/or enemy
Uncontrollable shaking and/or panic attack
Past and/or possible future events
Witnessing a crime
Fear of leaving the house or going to a specific place
Getting lost in one's own house or some other familiar place
Relatives and/or friends dying or disappearing
Event of a disaster
Performing the same or similar routine
Visiting the same or similar place
Desire for a specific need or craving
Sexual stimulation (sometimes)
Other forms of stimulation
Visiting or seeing recognizable people, animals, objects, buildings, etc.
Being alone
Being in a helpless situation
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