Mental illnesses that are not purely psychological in nature can be roughly divided into the following groups: schizophrenia, manic depression, paranoia, organic psychosis, and reactive psychosis.
非心理性因素精神病患的個別差異相當大，依照病程、疾病本質、預後的差異，精神病可以概略分為：精神分裂症、躁鬱症（情感性精神病）、妄想症、器質性精神病及反應性精神病等。