Vivid dreams are associated with a high percentage of REM sleep: a prospective study in veterans.

STUDY OBJECTIVES: Vivid dreams are dreams that feel real or are associated with dream enactment behavior. They are prevalent in veterans, especially in those with psychiatric disorders such as post-traumatic stress disorders. Such psychiatric disorders have known association with abnormalities in rapid eye movement (REM) sleep. Vivid dreams are also described in neurological conditions, such Lewy body dementias, which are also associated with REM sleep abnormality. Although vivid dreams occur in neuropsychiatric disorders that have REM sleep abnormalities, there are no studies that have directly investigated an association between vivid dreams and REM sleep. We sought to study vivid dreams and REM sleep in veterans. METHODS: Veterans undergoing polysomnography at our hospital were invited to enroll. Participants completed a dream-related questionnaire the morning after their polysomnography. RESULTS: We prospectively enrolled 505 veterans. After a night in the sleep laboratory, 196 of 504 (39%) reported experiencing a dream, and, of those, 117 of 190 (62%) described their dream as vivid. Discrepancies in patient totals are secondary to missing questionnaire data. Our novel finding is that participants with a high percentage of REM sleep (above 25%) were more than twice likely to report a vivid dream than participants with a lower percentage of REM sleep (P < .0001). Nonvivid dreams were not associated with a high percentage of REM sleep. CONCLUSIONS: Vivid dreams are associated with a high percentage of REM sleep. Further research into the role of REM sleep abnormalities in vivid dreams may help to advance understanding of neuropsychiatric disorders. CITATION: Fattal D, Platti N, Hester S, Wendt L. Vivid dreams are associated with a high percentage of REM sleep: a prospective study in veterans. J Clin Sleep Med. 2023;19(9):1661-1668.

Ocular Lateral Deviation as a Vestibular Sign to Improve Detection of Posterior Circulation Strokes: A Review of the Literature.

BACKGROUND: Posterior circulation stroke can present with dizziness/vertigo without other general neurological symptoms or signs, making it difficult to detect, and missed stroke can deteriorate. Therefore, a sign that can be easily identified during an examination would be helpful to improve the detection of this type of stroke. OBJECTIVE: The objective of this review is to highlight an ocular sign that is seen in posterior circulation strokes called ocular lateral deviation (OLD). OLD is mostly seen in dorsolateral medullary strokes, and it is also seen in pontine and cerebellar strokes. OLD is detected by asking a patient to look straight ahead and then briefly close their eyes. Upon re-opening their eyes, the examiner will see that the eyes have deviated to one side; the patient's eyes will then make corrective saccade(s) to return to looking straight ahead. Complete eye deviation is a central sign of posterior circulation stroke. DISCUSSION: OLD is an under-recognized vestibular ocular sign of central vestibulopathies including posterior circulation stroke. The most common location is in the dorsolateral medulla, where one-third of such strokes have complete OLD. Eye deviation can also be appreciated on computed tomography or magnetic resonance imaging. OLD can be detected up to 6 months after a posterior circulation stroke. CONCLUSIONS: Checking for the sign of complete eye deviation in patients with dizziness/vertigo could be a simple, quick method for detecting posterior circulation stroke, and a means to improving the patients' outcome.