Can optogenetics stop binge drinking and drug abuse?

A team of researchers from Wake Forest University and the University at Buffalo have successfully switched off the desire to binge on alcohol using optogenetics. This suggests that it could one day be possible to treat people in a similar way.

The researchers first had to train rats to binge on alcohol. The rats were then deliberately infected with a virus that delivered a light-responsive protein called channelrhodopsin-2 (ChR2) to the dopamine-controlling neurons. Once the proteins were in place, light was used to stimulate their dopamine-controlling neurons; this resulted in the rats refusing to drink.

The lead researcher, Caroline E Bass, said: “For decades we have observed that particular brain regions light up or become more active in an alcoholic when he or she drinks or looks at pictures of people drinking, for example, but we didn’t know if those changes in brain activity actually governed the alcoholic’s behaviour.”

The neurons were activated using a type of deep brain stimulation that uses light instead of electricity to stimulate neurons. While electrical stimulation has had some success in treating other conditions, this is far from ideal because it affects all the neurons. Optogenetics allow doctors to stimulate specific neurons and control desire.

This new research could lead to other treatments; the neurons that were targeted were in the part of the brain known as the nigrostriatal pathway, which is connected with Parkinson’s disease. Dr Bass believes that it is possible that one day we will be able to cure Parkinson’s using a similar method.

There is currently no plan to use optogenetics on humans; furthermore, some scientists are not keen on the idea of optogenetics at all, as mental health is still a very misunderstood area. The researchers did successfully stop the rats from binge drinking but they have no way of knowing if the treatment caused serious adverse effects to their mental health.