The exact cause of bipolar disorder has not been determined; however, for most patients

A) several factors, including genetics, are implicated.
B) brain structures were altered by stress early in life.
C) excess sensitivity in dopamine receptors may trigger episodes.
D) inadequate norepinephrine reuptake disturbs circadian rhythms.

Bipolar Disorder

A mental illness characterized by significant mood swings, including periods of depression and periods of mania or hypomania.

Dopamine Receptors

Proteins located in the brain and nervous system that respond to dopamine, a neurotransmitter involved in motivation, pleasure, and motor function among other pathways.

Genetics

The study of genes, genetic variation, and heredity in living organisms.