A. Persistent or recurrent hallucinations are the predominant clinical feature.
B. No clouding of consciousness, as in Delirium; no significant loss of intellectual abilities, as in Dementia; no predominant disturbance of mood, as in Organic Affective Syndrome; no predominant delusions, as in Organic Delusional Syndrome.
C. Evidence, from the history, physical examination, or laboratory tests, of a specific organic factor that is judged to be etiologically related to the disturbance.
Other Organic Mental Disorders
In Delirium, hallucinations, if present, occur with clouding of consciousness. In Dementia, hallucinations, if present, are associated with a general loss of intellectual abilities. In Organic Delusional Syndrome, hallucinations, if present, are overshadowed by the prominent delusions.
Schizophrenia and Affective Disorders may involve hallucinations, but no specific organic factor can be demonstrated.
Hypnagogic and hypnopompic hallucinations
Hypnagogic and hypnopompic hallucinations may occur in individuals without a mental disorder, but they occur only on falling asleep or on awakening.