Bowles Center for Alcohol Studies Researcher Donita Robinson, Ph.D., recently received a Research Project Grant (R01) from the National Institutes of Health’s National Institute on Alcohol Abuse and Alcoholism. Totaling just over a million dollars, the five-year grant project will examine dopamine release and neural activity in rat models of habitual alcohol drinking and cue-induced relapse.
The project, titled ‘Habits and cues in alcohol drinking: Dynamic striatal activity,’ will look at the major factors that contribute to continued alcohol drinking, such as the learning processes underlying habit formation and the degrees to which habits versus goal-directed behaviors that drive drinking may influence the susceptibility to relapse.
“Alcoholism is a chronic disorder that typically spans several decades and may be perpetuated by learned, habitual behavior. Operant conditioning paradigms in rats can model the contribution of habit to alcohol drinking and allow direct measurement of brain function during these behaviors,” said Robinson. “We know that the dorsomedial striatum (DMS) underlies goal-directed behavior while the dorsolateral striatum (DLS) is crucial for habit formation.”
Robinson says both DMS and DLS contribute to animal models of relapse. Dopamine input is essential to the association between cues and drugs and has profound and region-specific effects on synaptic plasticity, neuronal activity and behavior. Robinson and team will test the overall hypothesis that subsecond dopamine release and ongoing neuronal activity differ in DMS and DLS, with the DMS preferentially active during goal-directed alcohol reinforcement and the DLS preferentially active during habitual alcohol reinforcement and cue-induced relapse.
State-of-the-art, real-time recording techniques will measure dopamine transients and single-unit activity of medium spiny neurons in the dorsal striatum. Robinson and team will make the combination of chemical and physiological measurements during goal-directed and habitual alcohol drinking, as well as relapse-like behavior. “Our measurements will provide the most complete picture to date of dorsal striatal encoding of alcohol-related habit formation,” said Robinson.
Data from this study will provide important information on how the dorsal striatum differentially encodes goal-directed versus habitual alcohol drinking. “We think that these studies could potentially identify novel mechanisms by which habitual alcohol drinking leads to changes in brain and behavioral processes,” said Robinson. “That data would be of crucial importance to understand the development and treatment of alcohol abuse and alcoholism.”