New Research on Reward and Anxiety Areas in the Brain May Help Treat Addictions

For the first time researchers are getting a look into how two different areas in the brain relate to each other to promote emotionally motivated behaviors and specifically those associated with anxiety and reward.

For this reason, researchers hope the new study will help scientists develop more powerful mental health therapies for conditions including addiction, anxiety and depression.

The research deals largely with the part of the brain called the amygdala, which is known for processing both memory and emotion. In particular the scientists looked at the BNST - a portion of the brain that becomes active when an individual experiences stress, 

As it turns out, neurons in the BNST reach into a portion of the brain involved in behavioral responses to reward - an area called the ventral tegmental area (VTA). For years now scientists have known that dopamine neurons located in the VTA are involved in rewards and motivation, including during drug abuse.

Garret Stuber, assistant professor in the departments of Psychiatry and Cell Biology and Physiology, and the University of North Carolina Neuroscience Center, wanted to better understand just what it means that these two seemingly opposite aspects of the brain are in fact connected.

To do so Stuber and his team used a technique called optogenetics. Only seven years old, it involves the transfer of ospins, light-sensitive proteins, into the brain cells. They then act like light bulbs, lighting up the cells where they reside.

As they did this in mice, stimulating them with a non-dangerous foot shock, scientists found that stimulating either of the cell pathways had the opposite effect on behavior. The excitatory neurons led to aversive behavior and the inhibitory cells the mice would actually spend more time in the area of the cage where they had received it.

"Because these cells are functionally and genetically distinct from each other," Stuber states in an article posted on UNC's website, "our findings also point to new potential targets for therapeutic interventions in neuropsychiatric disorders associated with alterations in motivated states such as addiction."