Abstract
Abstract Study Objectives Disorders of arousal (DoA) are diagnosed on the basis of clinical criteria, including inappropriate or absent responsiveness to communication attempts. Surprisingly, the ability of patients to interact with others during DoA episodes has not been systematically investigated. To address this gap, we conducted three studies. Methods First, we used a retrospective questionnaire to assess verbal responsiveness during episodes in 61 adult patients with DoA (Study 1). Second, we used auditory stimulation during polysomnographically verified N3 sleep to trigger DoA episodes in 14 patients. We then asked questions to test the possibility of verbal interactions during the episodes (Study 2). Third, we assessed the presence and quality of conversations with a bed partner in 364 home video-recorded episodes from 19 patients (Study 3). Results In Study 1, most patients (81%) reported occasional conversations during parasomnia episodes. Patients’ ongoing mental content influenced both their responses to questions during episodes and their perception of the outside world (including their surroundings and the identity of their interlocutor ). In Study 2, auditory stimulation had a limited effect in inducing episodes (7/157 trials). One patient indirectly responded to our verbal prompts in a DoA episode. In Study 3, we found 37 video instances of discussion between patients and their partner. Conclusions Overall, our findings suggest that DoA episodes are not a uniform state but may instead encompass varying states of consciousness, characterized by different levels of responsiveness and a complex interplay between internal and external information processing. These results highlight the limitations of current diagnostic criteria for DoA.