Delving into drug addiction
A reformed drug addict meets up with old drinking buddies or stops by a former hangout. Will that trigger a relapse? If the person is a woman, the chances could be higher.
Drug use in women has climbed in recent years, according to the National Survey on Drug Use and Health, and studies indicate that women move from casual to chronic use more quickly than men. Yet research on addiction in women continues to lag.
Psychology Assistant Professor Linda Perrotti explores the differences in how men and women respond to drug reward. Using cellular, molecular, and behavioral procedures, she is working to better understand drug abuse and addiction.
In 2010, the last year for which figures are available, 22.6 million Americans reported using illegal drugs, according to the national survey. That same year, 4.1 million sought treatment for addiction.
“What makes one person a casual drug user, while another becomes an addict? Why are some individuals more susceptible to drug abuse than others?” Dr. Perrotti asks. “Answering these questions could have major implications.”
In one experiment, she and her team administered cocaine to rodents every other day in the same location. On off-days they administered saline injections in a different location. The regimen lasted two weeks.
After a month without drugs, the rats were placed in a neutral location and left to wander. The researchers found that the female rats were twice as likely to enter the cocaine chamber.
“This tells us that women develop a much greater attachment to environmental factors,” Perrotti says. “A reminder of a person, place, or time is the No. 1 cause of relapse, even more than stress or cravings.”
She is now studying the effects of estrogen and progesterone on drug-seeking behavior. Higher levels of estrogen have been linked to increased likelihood of addiction, possibly because estrogen boosts the release of dopamine, which is associated with reward-seeking behavior.
Eventually, Perrotti hopes to study how long it will take the rodents to extinguish the memory of the drug reward. The research could help counselors develop more effective, gender-specific rehabilitation and therapy, as well as pharmaceuticals to aid addiction recovery.
“We must always remember that our work carries importance beyond our own laboratories,” she says. “This research matters to millions of people and their families who suffer from drug addiction.”