What Are Visual Hallucinations?

In the broadest sense, a hallucination is a perception without a stimulus. They occur when a person is fully conscious and aware of her surroundings and appear to be vivid and substantial despite not being "real." In other words, a visual hallucination can best be described as seeing things that aren't there. Visual hallucinations can be caused by a number of factors, including drug use and various medical conditions.

Visual Hallucinations Caused by Exhaustion

• One cause of visual hallucinations is exhaustion or sleep deprivation. If a person is too exhausted or fatigued and goes too long without sleep, it is possible for the brain to be half asleep. This can be described as dreaming while one is still awake. The patient begins to see dreamlike images while awake and may have difficulty distinguishing what is real and what is imaginary. This is the most common and least-serious causes of visual hallucinations. It can usually be overcome with proper sleep and rest.

Migraines

• Migraine sufferers often report experiencing visual hallucinations in the form of auras that can appear before the onset of a headache. These can be described as unformed flashes of white and black or zigzag lines. Flashes of color can be seen as well. Some migraine sufferers complain of blurred, shimmery or tunneled vision before a headache strikes. These visual hallucinations can be unnerving for those who experience them for the first time or experience them infrequently enough so that they aren't used to them, but they are rarely debilitating. In the case of migraines, it is the headaches that are the major problem.

Drug Use

• Drug use is what most people think about when they imagine visual hallucinations. Marijuana is the most widely used illegal drug in the world, and it contains delta-9-tetrahydrocannabinol, or THC, that weakens brain cells and causes some hallucinations. LSD also is known to cause hallucinations, although the effect of the drug changes according to the user's mood. Psychedelic mushrooms are natural hallucinogens, and they can cause delirium as well as visual hallucinations. These drugs also cause alterations in auditory and visual reception, which may be a reason why they commonly incite paranoia in users.

Treatment for Visual Hallucinations

• The causes of visual hallucinations are varied enough that one standard treatment is impractical. However, there are methods of treatment that can work. Drug users who hallucinate because of the drugs that they use can enter rehabilitation to treat their addiction and get rid of the underlying cause of their hallucinations. Those who do not use drugs but hallucinate will have problems finding treatment. As with treating drug addiction, the answer lies in treating the underlying problems. Hallucinations that are caused by exhaustion and fatigue can be fixed with rest, and treatments for migraines may be able to help get rid of the auras experienced by migraine sufferers.