A neurosis is a psychic condition where patients earlier in life have encountered an unbearable psychic pain, which they were not able to process consciously. They have then unconsciously chosen to suppress the unbearable feelings and may not have any conscious memory of what happened earlier in life. This can be incest or other sexual abuse of a frightening nature, or other traumatic incidents. The patients do not remember the original incident, instead they get a nervous symptom which is experienced as the real disorder. The nervous symptom can be different kinds of abuse such as drug abuse, eating disorders, self-harm, anxiety, depression, sexual problems, etc.

In psychotherapy, the neurosis can be cured by letting the patient relive the suppressed painful and forbidden memories, and the feelings which were associated with them.

People who have a neurosis are aware that something is wrong. This is different from psychotic people, who live in a sick world and really believe that they are Jesus or really hear voices which no one else can hear.

Instead of using the term "neurosis", psychiatrists today prefer to use a more specific term for a specific disorder, such as "snake phobia".

Younger psychiatrist might have some problems to explain this term because it is no longer used in up to date psychiatric classifications. However, some doctors or psychologists still refer to neurotic concepts (psychoanalytic theory) opposed to "psychotic" syndromes or disorders (e.g. schizophrenia, or schizo-affective disorders, mania) Some therapists refer to neurotic anxiety disorder and refer to problems that are influenced by the personality and coping ability of the individuals.

The word "neurosis" describes "nerve disorder". William Cullen, physician of the late eighteenth's century tried to summarize a group of mental disorders without (obvious) organic cause.

Sigmund Freud adapted the concept of neurosis to mental disorders or distress with the major aspect of extreme anxiety. This concept investigates internal processes of personality and self-concepts (unconscious conflicts), related to the neurotic anxiety.

Examples of "neurotic" disorders are :

• Anxiety neurosis
• Depressive neurosis
• Somatization (formerly called "hysterical neurosis")
• post-traumatic stress disorder (PTSD)
• Obsessive-compulsive disorder

Psychic disorders often combine a neurotic factor with a non-neurotic factor. There may be genetic dispositions, which are stimulated by neurotic factors. For example, a person with OCD may check that the door is locked five times when stressed, but the stress may have neurotic causes.