14 DAY TRIAL // The neurochemical basis of addiction could potentially be targeted via a technique that would enable scientists to manipulate patterns of dopamine cell activation in the brain. This control mechanism, generically called optogenetics, allows neuroscientists to control single neural pathways, thus opening up treatment opportunities that were previously unavailable.
Optogenetics is a relatively new area of medicine that deals with using light to promote or inhibit the operations of specific groups of neurons. Basically, investigators can turn on or off various portions of the human brain, or the connections between them, with the flick of a switch.
Before optogenetics was developed, figuring out which neural connections were involved in various mechanisms was a very complicated process. Now, scientists can simply turn a set of neurons off, and see whether or not they were actually involved in underlying a specific action or process.
In a new study, researchers with the Wake Forest Baptist Medical Center sought to understand the role of dopamine in alcohol drinking-related behaviors by using optogenetics. The team was led by assistant professor of neurobiology and anatomy Evgeny A. Budygin, PhD.
“With this technique, we’ve basically taken control of specific populations of dopamine cells, using light to make them respond – almost like flipping a light switch. These data provide us with concrete direction about what kind of patterns of dopamine cell activation might be most effective to target alcohol drinking,” he says.
Budygin and study co-author Jeffrey L. Weiner, PhD, a professor of physiology and pharmacology at Wake Forest Baptist, published details of their findings in a paper that appears in the latest online issue of the journal Frontiers in Behavioral Neuroscience.
“We have known for many years what areas of the brain are involved in the development of addiction and which neurotransmitters are essential for this process. We need to know the causal relationship between neurochemical changes in the brain and addictive behaviors, and optogenetics is making that possible now,” Weiner says.
In their research, which was focused on lab rats, the scientists were able to discover a set of distinct dopamine cell activation patterns that appear to interfere with, and disrupt, alcohol addiction mechanism in the rodents' brains, PsychCentral reports.
The research implies that techniques such as deep-brain stimulation may one day be used to treat alcoholism in humans as well. Low-intensity DBS is already used to treat anxiety and depression. “Now we are taking the first steps in this direction. It was impossible before the optogenetic era,” Bubygin concludes.