Background: One of the most important approaches is the sensitivity theory to strengthening with hypothesis of behavioral inhibition and activation systems in addiction and abuse of drugs upon which this research is based on. The purpose of this research is to study the differences between brain-behavioral systems in drug-dependent and normal individuals.

Materials and Methods: This is a casual-comparative study. The population of this study consists of all Urmia resident men and women aging from 20 to 50 years who were settled in addiction relief camps in October 2013. 120 testing addicted (80 men and 40 women) and 120 testing normal individuals (80 men and 40 women) whose age, gender and educations were similar to the addicted group were chosen by randomly sampling method. Measuring instrument of this research was Carver White’s questionnaire (1994) and the data was analyzed and compared by using dual-sample independent T testing method.

Results: The findings demonstrated that level of behavioral activation system in the addiction is higher than in normal individuals group and the level of behavioral inhibition system in normal individuals is higher than in addicted. Also, the findings expressed that behavioral activation system in men was more active than women and behavioral inhibition system in women is more active than men but was not observed significant difference in behavioral activation system between addicted men and women.

Conclusion: The findings were parallel with Gray Reinforcement Sensitivity Theory (1993) on the fact that consuming the drugs is caused by further activity of behavioural activation system