A differentiating empirical linguistic analysis of dreamer activity in reports of EEG-controlled REM-dreams and hypnagogic hallucinations.

Dream reports collected after REM sleep describe more physical movement by the dreamer, while hypnagogic hallucinations (the imagery experienced just before falling asleep) are mostly experienced passively, as an observer. The findings come from linguistic analysis of reports given immediately after EEG-monitored periods of hypnagogia and REM sleep in a sleep laboratory. The method, called Activity Analysis, quantifies the level of simulated motor activity in subjective reports. This approach could be used to study altered activity levels in conditions such as depression or PTSD.

Study at a glance

Abstract

We present Activity Analysis as a new method for the quantification of subjective reports of altered states of consciousness with regard to the indicated level of simulated motor activity. Empirical linguistic activity analysis was conducted with dream reports conceived immediately after EEG-controlled periods of hypnagogic hallucinations and REM-sleep in the sleep laboratory. Reports of REM-dreams exhibited a significantly higher level of simulated physical dreamer activity, while hypnagogic hallucinations appear to be experienced mostly from the point of passive observer. This study lays the groundwork for clinical research on the level of simulated activity in pathologically altered states of subjective experience, for example in the REM-dreams of clinically depressed patients, or in intrusions and dreams of patients diagnosed with PTSD.