Hypnagogic states are quite common: Evidence from a Swiss population

The hypnagogic state refers to experiences in different modalities, which sometimes occur in the transitional phase between wakefulness and sleep. While the hypnagogic state has been a topic of interest for over a century, its prevalence is still unclear. Moreover, the emotional nature of those experiences remains equivocal, from frightening to emotionally flat. The goal of this project was to investigate these questions in a healthy swiss population. In an ongoing web survey with currently 480 respondents, we assessed different states of consciousness, as well as their modalities. Further, we asked respondents about characteristics of their hypnagogic experiences and assessed cognitive, personality and behavioural influential factors. The preliminary results show that hypnagogic states occurred quite frequently, in 76.5% of respondents. The most frequent hypnagogic experiences were kinaesthetic (92%), visual (59%) and auditory (35%). Most often they occurred at sleep onset (85%), less often at sleep offset (26%) and rarely during the day (7%). Hypnagogic states were described as significantly less irritating than dreams, but similar in their emotional quality. Higher scores in unusual perception were associated with a higher occurrence of hypnagogic states, while higher scores in magical thinking and eccentric behaviour were associated with more pleasant hypnagogic experiences. In addition, higher anxiety was associated with more irritating hypnagogic experiences. Our findings indicate that hypnagogic states are very common and similar to dreams in their emotional quality.