First author Caroline E. Bass, PhD, assistant professor of pharmacology and toxicology in the UB School of Medicine and Biomedical Sciences explained that by stimulating certain dopamine neurons in a precise pattern, resulting in low but prolonged levels of dopamine release, they could prevent rats from binging. The rats just flat out stopped drinking.
In the experiments, rats were trained to drink alcohol in a way that mimics human binge-drinking behavior.
She said that the rodents continued to avoid alcohol even after the stimulation of neurons ended.
The researchers activated the dopamine neurons through a type of deep brain stimulation, but unlike techniques now used to treat certain neurological disorders, such as severe tremors in Parkinson’s disease patients, this new technique, called optogenetics, uses light instead of electricity to stimulate neurons.
Bass explains that electrical stimulation hits all the neurons, but the brain has many different kinds of neurons, with different neurotransmitters and different functions. Optogenetics allows you to stimulate only one type of neuron at a time.
Bass used a virus to introduce a gene encoding a light-responsive protein into the animals’ brains. That protein then activated a specific subpopulation of dopamine neurons in the brain’s reward system.
The findings have been published in journals Frontiers in Neuroscience.