| A | B |
| mental disorder | an illness of the mind that can affect the thoughts, feelings, and behaviors of a person, preventing him from leading a happy, healthful, productive life. |
| organic disorder | disorder that is clearly caused by a physical illness or injury that affects the brain. |
| functional disorder | disorders that may occur as the result of psychological causes in which no clear brain damage is involved. |
| anxiety disorder | an illness in which real, imagined, or persistent fears prevent a person from enjoying life. |
| phobia | irrational fears |
| obsessions | persistent, recurrent, unwanted thoughts or ideas that keep people from thinking about other things. |
| compulsions | urgent, repeated, irresistable behaviors |
| panic disorder | disorder that makes the individual feel anxious, fearful, and upset for no apparent reason. |
| post-traumatic stress disorder | condition in which a person experienced a traumatic event and feels the severe and long-lasting aftereffects. |
| somatoform disorder | an illness in which a person complains of disease symtoms, but no physical cause can be found. |
| affective disorder | illness often associated with an organic cause that relates to emotions and mood swings/extremes. |
| clinical depression | feelings of sadness, hopelessness, or despair last for more than a few weeks and interfere with daily activities. |
| bipolar disorder | psychological illness characterized by extreme mood swings between depression and extreme happiness, or mania. |
| personality disorders | psychological conditions that affect a person's ability to get along with others. |
| antisocial personality | characterized by a person's constant conflict with society. |
| schizophrenia | a serious mental disorder meaning "split mind". |