U.S. doctors online nowAsk doctors free
A 31-year-old member asked:

What causes illusions, delusions, and hallucinations?

1 doctor answer3 doctors weighed in
Dr. Steven Griggs
Clinical Psychology 40 years experience
Illusions are simple: perceptual distortions, seeing things that aren't there because of low lighting, atmospheric distortion, etc. Once light is shined on the cause, the illusion disappears. Delusions are fixed patterns of thought that do not respond to reality. Hallucinations are psychotic manifestations that have little to do with reality. The latter two are usually brought on by drugs or mental illness.
Created for people with ongoing healthcare needs but benefits everyone.

Similar questions

A 19-year-old member asked:

What is the difference between delusion, illusion, and hallucination?

5 doctor answers11 doctors weighed in
Dr. Douglas Bey
Psychiatry 58 years experience
Stimulus: Hallucination is a false perception while an illusion is a misperceptions of a real stimulus--hearing voices with no stimulus is a hallucination misinterpreting the sound of the radiator as voices is an illusion.
Created for people with ongoing healthcare needs but benefits everyone.
Dr. Douglas Bey
Dr. Douglas Bey commented
Psychiatry 58 years experience
Provided original answer
Delusion is a false belief that isn't altered by logic.
Feb 26, 2015

Related questions

A 35-year-old member asked:
How can I tell if i'm having delusions or hallucinations?
1 doctor answer5 doctors weighed in
A 31-year-old member asked:
I have delusions and hallucinations, but no sign of stroke, what is this?
1 doctor answer4 doctors weighed in
A 38-year-old member asked:
Do adults with fever get hallucinations or delusions?
3 doctor answers11 doctors weighed in
A 43-year-old member asked:
Are visual hallucinations a schizophrenic symptom also, or only delusions?
3 doctor answers4 doctors weighed in
A 32-year-old member asked:
Can a person suffering with schizophrenia not have delusions, just hallucinations?
3 doctor answers5 doctors weighed in
Last updated Jan 14, 2019

People also asked

Connect with a U.S. board-certified doctor by text or video anytime, anywhere.
24/7 visits - just $39!
50% off with $15/month membership


Content on HealthTap (including answers) should not be used for medical advice, diagnosis, or treatment, and interactions on HealthTap do not create a doctor-patient relationship. Never disregard or delay professional medical advice in person because of anything on HealthTap. Call your doctor or 911 if you think you may have a medical emergency.