You suddenly awake, and you found a phantom of your dead friend suspended in the mid-air. The ghost suddenly strides nearer then disappeared. Is this a ghost? A spirit manifested beyond death? Maybe. Psychologists, however have a plausible explanation for strange events like this.:

Graham Reed explained his hypothesis about ghost sightings in his book The Psychology of Anomalous Experience:

“The drowsiness experienced when one falls asleep, and again as one wakes up, is often accompanied by pronounced imagery… The intermediate state between wakefulness and sleep is referred to as hypnagogic; that which precedes full wakefulness after sleep is termed hypnopompic… Both hypnagogic and hypnopompic images are notably autonomous, in the sense that they occur suddenly and are not under voluntary control. Very often they are vivid and realistic, although their content may be bizarre.”

The most common type of hypnagogic visual imagery is probably the ‘’faces in the dark’’ which often terrify children as they are falling asleep, and which are also reported to some adults. The ‘’faces’’ are often distorted in size and shape, and may be in bright but unnatural colors.

Hypnagogic imagery may also be interpreted as a pathological phenomenon by adolescents and persons who are hypochondriac and worried about their mental health.