The equivalent transition to wakefulness is termed the hypnopompic state. Mental phenomena that occur during this "threshold consciousness" phase include lucid dreaming, hallucinations, out of body experiences and sleep paralysis.The collective noun "Hypnagogia" was coined by Dr Andreas Mavromatis[A] in his 1983 thesis (Brunel University) which was later published by Routledge (hardback 1987, paperback 1991) under the title ‘"Hypnagogia" the Unique State of Consciousness Between Wakefulness and Sleep’. The term "hypnagogia" is employed by Dr Mavromatis to include both sleep onset and the transition from sleep to wakefulness; he retains, however, the adjectives "hypnagogic" and "hypnopompic" for the identification of specific experiences.
A hypnopompic state (or hypnopomp) is the state of consciousness leading out of sleep, a term coined by the spiritualist Frederick Myers. Its twin is the hypnagogic state at sleep onset; though often conflated, the two states are not identical. The hypnagogic state is rational waking cognition trying to make sense of non-linear images and associations; the hypnopompic state is emotional and credulous dreaming cognition trying to make sense of real world stolidity. They have a different phenomenological character. Depressed frontal lobe function in the first few minutes after waking – known as "sleep inertia" – causes slowed reaction time and impaired short-term memory. Sleepers often wake confused, or speak without making sense. When the awakening occurs out of rapid eye movement (REM) sleep, in which most dreams occur, the hypnopompic state is sometimes accompanied by lingering vivid imagery. Some of the creative insights attributed to dreams actually happen in this moment of awakening from REM.
 Alfred Maury (1817–1892) was a French physician, important because his ideas about the interpretation of dreams and the effect of external stimuli on dreams pre-dated those of Sigmund Freud. He is mentioned by Freud in The Interpretation of Dreams, and by Sebastian Faulks in Human Traces. He coined the term hypnagogic hallucination and reported a dream that famously inspired Salvador Dalí's painting Dream Caused by the Flight of a Bee Around a Pomegranate a Second Before Awakening. Alfred Maury was contemporary with Hervey de Saint Denys and the two dream researchers were in disagreement with each other.
 Frederic William Henry Myers (1843–1901) was a classical scholar, poet, philosopher, and past president of the Society for Psychical Research.
Marie-Jean-Léon Lecoq, Baron d'Hervey de Juchereau, Marquis d'Hervey de Saint-Denys (1822 – 1892, Paris), was a French sinologist and man of letters, and one of the earliest oneirologists (specialists in the study of dreams).
[A] The name may sound confusing to those not familiar with the term "hypnogogic". Hypnogigia is a term coined by Dr Andreas Mavromatis which describes the images that you see while in between the waking and sleeping state. These are called hypnogogic images or hypnogogic hallucinations. They are naturally occurring and everyone sees them, especially just before falling asleep.
Some people have found them annoying, especially when they come in the form of simple objects, scenes, or people. Other times, they can be scary, as in taking the shape of a frightening face, and when the mind is more conscious, it's natural for them to be seen as flashes of light.