Hallucinogen Persisting Perception Disorder (HPPD)

While there are many reasons why individuals may suffer difficulties with their perception, a disorder known as HPPD, or Hallucinogen Persisting Perception Disorder is one that is caused by the usage (once or more) of Hallucinogeic drugs, primarily LSD but not limited to Peyote, Mesculine and Psilocybin. What a person suffering from HPPD sees can vary from one individual to another and does not occur constantly. The characteristics that one must display in order to classify them as one who has the disorder includes the transient recurrence of disturbances in perception that mimic those experienced during one or more earlier Hallucinogen Intoxications (also known as "trips"). According to the DSM-IV, "the person must have had no recent Hallucinogen Intoxication and must show no current drug toxicity (Criterion A). This re-experiencing of perceptual symptoms causes clinically significant distress or impairment in social, occupational, or other important areas of functioning (Criterion B). The symptoms are not due to a general medical condition (e.g., anatomical lesions and infections of the brain or visual epilepsies) and are not better accounted for by another mental disorder (e.g., delirium, dementia, or Schizophrenia) or by hypnopompic hallucinations (Criterion C)."

To more specifically talk about what a person with Hallucinogen Persisting Perception Disorder may see I have included a short-video at the bottom of this post which claims to simulate the effects of HPPD in some variation. The perceptual disturbances one may experience can range from geometric forms, peripheral-field images, flashes of color, intensified colors, trailing images (images left suspended in the path of a moving object), perceptions of entire objects, afterimages (a same-colored or complementary-colored "shadow" of an object remaining after the removal of the object), halos around objects, macropsia, and micropsia--a few more common term used to describe some of these disturbances are flashbacks, illusions, or hallucinations. Individuals with the disorder may also experience tactile illusions, gustatory illusions, and smell odors that are not there. Really what an individual may experience varies, as mentioned before. An article that I found that provides adequate information about the subject is http://www.erowid.org/archive/rhodium/pdf/hppd.review.pdf

HPPD Simulator Demo
http://youtu.be/Kgy0WY5eH1w