Behavioral Science

86 Deja Review: Behavioral Science
What is the difference between
a hallucination and an illusion?
Name the six major primary psychotic
disorders.
Other than primary psychotic disorders,
what other types of psychiatric illness
often manifest psychotic symptoms?
An illusion is the misperception of
an actual sensory stimulus (eg, seeing
a pool of water on the road ahead
during a hot summer day),
whereas hallucinations are
perceptions in the absence of
an external stimulus.
1. Brief psychotic disorder (6 months of
symptoms)
4. Schizoaffective disorder
5. Delusional disorder
6. Shared psychotic disorder
• Mood disorders: Major depression or
manic episodes may include psychotic
symptoms, but only during a mood
disturbance.
• Substance use: Acute intoxication
(especially with cocaine, lysergic acid
diethylamide [LSD], phencyclidine
[PCP], and amphetamines) or
withdrawal (especially alcohol).
Anytime a patient has tactile
hallucinations, you should think
about drugs.
• Personality disorders: May be
associated with brief (not sustained)
periods of psychosis.
• Cognitive disorders: Both delirium
and dementia demonstrate psychosis.
Often delirium will have visual
hallucinations in addition to clouded
sensorium.
• Psychosis due to a general medical
conditions such as Vitamin B 12
deficiency, Multiple Sclerosis (MS),
Systemic Lupus Erythematosus (SLE),
uremia, etc.
• Narcolepsy: May have
hypnagogic and hypnopompic
hallucinations.