Research on personality and substance use has shown that some traits of personality might be involved in the onset and later development of addictions. According to Gray's Reinforcement Sensitivity Theory (RST; Gray, 1981), there are two basic brain systems that control behaviour and emotions (Corr, 2004): the Behavioural Inhibition System (BIS) and the Behavioural Activation System (BAS). It has been suggested that high levels of BAS sensitivity predispose psychopathological conditions that are characterized by a pathological engagement in approach behaviours, such as alcohol and drug abuse (Franken, Muris, Georgieva, 2006)

The aim of the present research was to analyse individual differences in the BIS and BAS in a sample of cocaine dependent patients in comparison to a non-clinical population group.

To carry on this study a number of BIS/BAS related scales were administered in a sample of 30 cocaine dependent patients and in a non-consumers control group of 30 participants recruited from general population.

Cocaine addict patients showed higher BAS scores, specifically in Sensitivity to Reward, Non-planning Impulsivity, Motor Impulsivity and Cognitive Impulsivity in comparison to the control group. Moreover, the Disinhibition scale, of the Sensation Seeking Scale, a measure also related to BAS activity, predicted age of onset of cocaine consumption.

These results suggest that BAS might be a vulnerability factor of cocaine misuse, while BIS might be a protector factor.