Interviewing Dr. Mark Gold: Cocaine Addiction and the Brain
A discussion on how cocaine addiction robs users of the ability to be insightful
Someone familiar with addiction knows that people who abuse drugs often engage in risky and dangerous behavior and don’t seem to think—or care—what happens. When we think about these kinds of people, we often think about creative figures like John Belushi or Chris Farley or Robin Williams. We picture their incredible skills being lost over time as their focus shifts and the search for the next drink, or fix, takes precedence over anything else, which is what happens.
Dr. Mark Gold has pointed out that one striking observation at physician addiction recovery meetings is just how much a neurosurgeon addict comes to look like an addict who never graduated from high school and is working in a fast food restaurant. That makes me think of my opening statement – that people suffering from addiction may say they just didn’t think about the consequences at that moment, or had no hope, or didn’t care.
But actually, according to a study using rats, reported in Nature Neuroscience magazine, cocaine addiction can rob a person of his or her ability to be insightful, which helps to explain why people relapse. However, the study also found that activating a part of the brain can restore that ability.
Q. Dr. Gold, did I summarize the point of the article correctly? Can you elaborate?
A. Loss of insight is an important contributor to failure in weighing risks vs. reward. Insight helps us see clearly the consequences of actions, and loss of insight often leads to relapse. Insight has recently been localized to a discrete brain area. It’s correlated with medial and orbital prefrontal cortical circuits in humans and animals. A new study in rats by researchers at NIDA’s Intramural Research Program found that cocaine self-administration reduced the animals’ ability to “insightfully” guide their behavior. Clearly, cocaine hijacks the brain and changes behavior. But does it change the brain in a way that makes recovery impossible? Some early studies that we did with Jean Lud Cadet’s NIDA group with methamphetamine have suggested that meth targets the brain cells, hijacks them, and causes head trauma-like damage to them.
However, and remarkably, normal behavior was temporarily restored in the rats by optogenetically activating those OFC pyramidal cells, suggesting that this circuit is not incapacitated or destroyed. Abstinence from cocaine can be associated with the return to normal function. Also, the study confirms that it is crucial to insight capacity that is compromised by drug abuse.
Q. How do you activate a part of the brain to restore the ability to be insightful?
A. Currently, we have utilized a model of health eating, rest, recovery, abstinence, moderate exercise, yoga and mindfulness. The program of recovery takes much longer than most recognize. Using PET imaging of dopamine systems, Gene Jack-Wang’s group at Brookhaven National Laboratory has shown that recovery is not 100% with abstinence, but it is slow and many cocaine addicts do not show recovery of dopamine systems even at six months of abstinence.
Q. What hope does this hold for those suffering from addiction?
A. The findings suggest that the OFC may offer a promising neural target for future interventions in addiction. Currently we do not have a way to activate or selectively activate the human brain to preserve or restore insight. Mark George, M.D., at MUSC, has been using transcranial magnetic stimulation (TMS) in clinical trials and believes this modality may be useful in addiction treatment and recovery.