Subjects with a history of drug dependence are more aggressive than subjects with no drug use history.

Aggressive responding was compared between 29 subjects with a history of substance dependence and 24 subjects with no drug use history, using the Point Subtraction Aggression Paradigm. The hypothesis was that subjects from the substance dependence history group would emit more aggressive responses than subjects with no drug use history. The substance dependence history group emitted more aggressive responses per session than the non drug using group (F(1,49) = 14.867, P = 0.032). These results are consistent with previous studies that have reported an association between aggression and drug abuse or dependence.