Abstract: Addiction is apparently affected by psychological factors. Personality factors are powerful etiologic factors in addiction, especially the sensation seeking trait. It’s argued that the mesolimbic dopamine system of the brain is the same reward mechanism for the sensation seeking and drug abusing. The DNA variants of the dopamine D4 receptor gene are associated with the personality traits of sensation seeking and the behavior of drug abusing. The influence of sensation seeking on addiction is mediated by environmental factors as family and peer. The psychometric instruments employed to sensation seeking addicts are also discussed.

Key words: Addiction Personality sensation-seeking