Pihl has made major contributions to the fields of clinical and health psychology in his more than 250 publications on various topics such as alcohol aggression, substance abuse, and pharmacology.
He received his PhD in 1966 under the supervision of Joel Greenspoon, a clinical psychologist and leading researcher in behavioral analysis.
[5] Pihl's research addresses psychopharmacology, alcohol, aggression, substance abuse, behavior modification, the cognitive consequences of addiction, and several risk factors for disorders.
Some of Pihl's early research projects involved the hair analysis of children with learning disabilities.
Pihl later conducted similar analyzes in which he also found greater levels of lead and cadmium in the hair of violent criminals, compared to the normal population.
[11] Some of his most notable research publications include: Pihl previously directed the department of psychology at the Lakeshore General Hospital in Montreal.