Studies. There appears to be an interaction between stress and the start of drug use and/or in relapse (e.g., reawakening a learned behavior). Stress can induce long term potentiation in cells that release dopamine in the VTA (ventral tegmental area) of the brain. (Zickler, Patrick. Addictive Drugs and Stress. MD: National Institute on Drug Abuse, NIDA NOTES, Vol 18, No 5, Dec 2003, pp 1, 6-7)
Refer to Stress and the Brain for additional information.