Shadow people
Shadow people are a common hallucination for humans to have. They usually appear as a result of sleep deprivation, drug use, or hypnagogic states. During this experience the subject perceives a patch of shadow in their peripheral vision to be a living figure. This can be either animal-like or humanoid in appearance. This hallucination is often accompanied with a feeling of intense paranoia and anxiety.
The visual hallucinations are initially fleeting images always out of the corner of the eyes. As time progresses, however, the hallucinations may appear in full view and one will be able to look directly at them. The bodies of the shadow people are usually entirely black with few features. They sometimes appear to have faces and are able to move or change shape.
These hallucinations are often perceived as being malicious due to intense paranoia and anxiety that often occur simultaneously. Tactile hallucinations, feelings of convincing physical sensations that are not actually occurring within reality, may occur. Auditory hallucinations may also manifest themselves, causing one to perceive that the shadow people are talking to them.
Psychoactive substances
Compounds from our psychoactive substance index which may cause this effect include: