A psychobiological model of personality and psychopathology

A seven dimensional model of personality permits the efficient differential diagnosis of all personality disorders and accounts for comorbidity with other psychopathology including psychosomatic illness. The presence or absence of any personality disorder is indicated by underdevelopment of the character traits of self directedness, cooperativeness, and self transcendence. Specific subtypes of personality disorder are indicated by the profile of temperament traits including novelty seeking, harm avoidance, reward dependence, and persistence. All seven traits can be rated by either interview or self report using a test called the Temperament and Character Inventory (TCI). Using the TCI, temperament types can be specified so that they are mutually exclusive so as to avoid multiple overlapping diagnoses. The temperament traits have been shown to be genetically homogeneous anti independent with heritabilities of about 50% each. The configuration of character traits determines susceptibility to psychopathology including schizophrenia, mood and psychosomatic disorders. For example, the 'type A' coronary prone person is hostile (low cooperativeness), conventional (low self transcendence), and assertive (high self directedness). The melancholic character is low in all three character dimensions, whereas creative characters are high in all three. Cyclothymics are high in self transcendence and cooperativeness but low in self directedness. Schizotypals are high in self transcendence but low in the other two character dimensions. The TCI is based on a conceptual paradigm that integrates neurobiological, psychodynamic, sociocultural, and cognitive behavioral approaches to normal and abnormal personality. It provides a clinical method of differential diagnosis of Axis 1 and Axis 2 psychopathology that is practical, reliable, and valid.