FRANÇAIS :
Il est supposé que le comportement addictif s'intègre dans un modèle psychologique. Les habitudes sont acquises parce qu'elles servent une fonction utile à l'individu, liée à la personnalité de celui-ci. La cause en serait un fonctionnement excessif de la dopamine. C'est déjà le cas pour les personnalités psychotiques, or les psychoses sont très souvent liées à des addictions. Il semble clair qu'une relation causale lie la personnalité et les facteurs biologiques, pour donner un comportement addictif.

ENGLISH :
It is suggested that addictive behaviour, so called, fits into a psychological resource model. In other words, the habits in question are acquired because they serve a useful function for the individual, and the nature of the functions they fulfil is related to the personality profile of the "addict". For some people this resource function develops into a form of addiction, and it is suggested that the reason this occurs is related to excessive dopamine functioning. This in turn is used to suggest the nature of the addictive personality. Excessive dopamine functioning is related to the personality dimension of psychoticism, and evidence is cited to the effect that psychoticism is closely related to a large number of addictions. The precise reasons for the addictive effects of dopamine are still being debated, but clearly there is a causal chain linking personality and biological factors together in the production of addictive behaviour.