An online survey of 380 people who had experienced sleep paralysis at least once found that more frequent episodes were associated with more phenomena, emotions, and perceived shapes during the event. Some individuals appeared to habituate and de-dramatize the experience with higher frequency. Contrary to expectations, neither general stress nor poor sleep hygiene correlated with episode frequency. Women reported more phenomena and emotions overall, more intruder and incubus-type episodes, and were more likely to perceive concrete forms like human figures. They also reported more fear, especially fear of going crazy. These exploratory findings require replication.
Sleep paralysis is linked to some extraordinary experiences and paranormal beliefs, but not all. An online survey of 380 people who had experienced at least one sleep paralysis episode found a significant correlation between how often sleep paralysis occurred and scores on the Dissociation and External dimensions of a questionnaire about extraordinary experiences. However, no such link was found with other scales measuring paranormal beliefs or absorption. Among the 55% of participants who reported paranormal experiences during sleep paralysis, scores on all three scales were significantly higher. The results suggest two possible types of sleep paralysis experience: one tied to negative emotions and external focus, another to positive emotions and internal perceptions, but this hypothesis needs further testing.