Hypnagogic states are quite common: Evidence from a prevalence study with young adults.

The hypnagogic state refers to the transitional phase between wakefulness and sleep during which vivid experiences occur. There is, however, great ambiguity in the reported prevalences of this phenomenon. In this study, we assessed the prevalence of hypnagogic states and the frequency of experiences in different modalities (visual, auditory, tactile, kinaesthetic, olfactory and gustatory) in three adult samples of a total of 4457 participants. We also asked them to rate their emotional quality, how irritated they felt by their experiences, and how vivid their experiences were. Moreover, we compared hypnagogic states to other states of consciousness, such as dreams, sleep paralysis, imagination, and extra-sensory perception. Hypnagogic states occurred in up to 81.5% of participants and prevalence was comparable across samples. Experiences were most often kinaesthetic (90.3%) and visual (70.9%), and less often auditory (43.1%), tactile (38.3%), and olfactory or gustatory (24.6%). Hypnagogic states were less prevalent than dreams and expressed a different profile of modalities in which they occurred, but were comparable in their emotional quality, the irritation they caused, and their vividness. In conclusion, hypnagogic states are quite common.