How Can You Tell What Causes Delusions And Obsessions?

QUESTION:

Dear Dr. Heller,

I just wonder what the difference is between schizoaffective disorder (bipolar type) and a bipolar disorder with psychotic features?  I have schizoaffective disorder and I go through periods of depression and mania.  I've also had delusional thinking and hallucinations (auditory).  I also have OCD and Tricotillomania.  So my second question is where does an obsession stop and a delusion begin?  How can you tell if a thought is an obsession or a delusion?

Thanks.

ANSWER:

Schizoaffective means schizophrenia with a mood disorder. 

Bipolar with psychotic features means the individual with bipolar gets psychotic symptoms. 

Psychosis simply means misinterpreting reality and can have many causes.  Delusional thinking and hallucinations can occur from any psychotic experience. 

An obsession is a persistent thought process that won't stop.  It's very intrusive but has a rational basis.  A delusion is a misinterpretation of reality.