Date of Award


Degree Name

Master of Arts



First Advisor

Dr. Cynthia J. Pietras

Second Advisor

Dr. Wayne Fuqua

Third Advisor

Dr. Alan Poling


Methadone, aggression, PSAP, Point Subtraction Aggression Paradigm, opioid deprivation

Access Setting

Masters Thesis-Open Access


Research suggests that current heroin users and individuals with a prior history of heroin dependence tend to be more aggressive than nonusers. No study has yet investigated whether opioid withdrawal affects aggressive responses on a laboratory task. The present study investigates whether mild opioid withdrawal affects aggression in six males and six females (N=12) undergoing methadone maintenance therapy. Aggressive behavior is measured using the Point Subtraction Aggression Paradigm (Cherek, 1981) computer task. Participants press buttons to earn money towards gift certificates. Money subtractions occur periodically and these are attributed to the behavior of a partner who is actually fictitious. Participants respond to protect their earnings or respond to protect their earnings while also subtracting money from the partner (the aggressive response option). Behavior on the PSAP is measured on two separate days; once prior to and once following the participant’s daily methadone dose. There are no differences in rates of aggressive responding on the PSAP or in self-reports of mood across conditions. These data suggest that the opioid deprivation occurring 24-hrs following methadone administration in individuals undergoing MMT does not produce heightened aggression, at least on this task in these generally non-violent participants.

Included in

Psychology Commons