dormendo

Dormendo is a term used in some sleep-science and popular psychology writings to denote a transitional state between wakefulness and sleep. The word is formed from the Italian dormire meaning "to sleep" and the gerund ending -endo, literally "sleeping." In this usage, dormendo refers to a broader window of reduced arousal that encompasses the moments just before sleep onset (hypnagogia) and brief periods of drowsy wakefulness that do not reach full sleep. Distinctions among dormendo, hypnagogia, and microsleeps are debated; some researchers describe dormendo as a continuum rather than a discrete stage, characterized by slowed EEG activity, lowered responsiveness, and occasional dream-like mentation without full stage criteria.

Measurements of dormendo typically note slowed brain activity with patterns that may include increased theta waves and decreased alpha activity, along with reduced sensory responsiveness. Autonomic markers such as heart rate variability can change, and electromyography may show occasional muscle relaxation. The duration of dormendo is variable, ranging from a few seconds to several minutes.

Origin and usage of the term are limited to a minority of texts and online communities, and it is not part of standard sleep stage classifications used by bodies such as the American Academy of Sleep Medicine or the International Classification of Sleep Disorders. Critics argue that dormendo can blur concepts and hinder clarity when describing sleep physiology.

Research and applications are mainly exploratory. Some wellness writers use dormendo to describe a state of "calm drowsiness" that may be cultivated through mindfulness, lighting, or traditional sleep hygiene practices; however, there is little rigorous evidence that treating dormendo as a distinct stage provides benefits beyond established approaches to sleep health.

See also: Hypnagogia, Sleep onset, Microsleep, Sleep stage classification.