I am a psychotherapist, and I too suffer from severe night terrors. I am currently working on a dissertation for my doctorate in clinical psycholgy, and I am coming accross some information that may help some people out there with questions about possible theoretical reasons for them. This next exerpt is from John Bowlby, the founder of Attachment theory.
...seperation from an attachmetn figure (in life) is found to be one of a class of situations of which is likely to elicit fear reactions but have no intrinstic nor real danger behind these reactions. These situations comprise amongst others darkness, sudden large changes of stimulii level including loud noises, sudden movement, strange people, and strange things. Evidence shows that many species are alarmed by similar situations, and that this is true of human adults and children. Furthermore fear is likely to be elicited when two or more of these stimuli are present simultaneusly, for example hearing a loud noise when alone in the dark. The explanation as to why individuals should so regularly respond to fear to these situations is because even thought these situtions are not dangerous in themselves, each carries with it an [i]increase risk[/i] of danger. Noise, strangeness, isolation, and for many species, darkness, are all conditions statistacallly associated with an increased risk of danger. Noise may be a warning of a natural disaster, like fire, floods, or landslides. To a young animal, a predator is strange, it moves, and it often strikes at night, and it is more likely to do so when the potential victim is alone. Because to behave so promotes survival and breeding success, the theory runs, the offspring of species that have survived, including man, have been genetically predisposed and biased to have developed an increased response to the properties of noise, strangeness, sudden approach, and darkness by avoiding action or running away-they behave in fact as if danger were actually present. In a comparable way they respond to isolation by seeking company (hence getting appropriate attachment and bonding). Fear responses elicited by such naturally occuring clues to danger are part of a mans basic behavioural equipment.
Fear seems to be a common explanation for the experience of NT type hallucinations however many people do not experience fear prior to experiencing the hallucinations. From current research into the causes for such behavior its more likely that NT's are a result of complication in the process of modulation or demodulation of the brain. This fear that many people experience could be explained by the hyperactive amygdala during the modulation into REM sleep. Yes I know NT's dont happen during REM sleep, however during the first complete phase of sleep the sleep phases do go through the process of 1-5 (in that order) and after jump from 2-5 making it possible for the NT to fall into a REM like cycle. Determining if the individual is pushing into REM while experiencing a NT is practically impossible. With that, most NT's happen in the first few instances of sleep. The real problem behind NT's is that the majority of sleep disorder doctors don't know how to treat the problem let alone properly diagnose the disorders. You commonly have individuals that experience the old hag syndrome expressing that they have NT's when they are completely different events and occur in different phases of sleep. We need more doctors keeping up on the current research into NT or even the last 30 years of research and break the trend of bad medical practice. We need to stop looking to Freud for the answers and start paying attention to individuals like Dr. Hobson and his activation synthesis theory.