Research Mentor(s): Jonathan Morrow, Associate Professor
Research Mentor School/College/Department: Psychiatry, Michigan Medicine
Presentation Date: Thursday, April 22, 2021
Session: Session 4 (2pm-2:50pm)
Breakout Room: Room 12
This project aims to develop an understanding regarding the neurobiology of vulnerability to addiction and post traumatic stress disorder (PTSD). Oftentimes when different environmental cues that have been associated with something emotional are triggered, it can lead to an emotional or motivational state that influences the way one behaves and can lead to undesirable consequences. For example, drug-associated cues including seeing or smelling drugs can induce craving which can lead to drug use or relapse. We are particularly interested in the neuronal basis on incentive salience – the cognitive process that attributes a “desire” or “want”, which includes a motivational component, to a rewarding stimulus. To investigate this phenomenon, our lab experiments with animals, particularly rats, and introduces a lever cue followed by a food reward in the cage. A distinction between rats is made: Rats who consistently approach the lever are known as sign-trackers (STs), rats who mainly ignore the lever and go straight to the location of the food are known as goal-trackers (GTs), and then there are unassigned rats who do not particularly show interest in the lever or the place where the food will come down, until the food is given. It is evident that STs attribute incentive value to lever while GT rats attribute predictive value to the lever as they go to the location where the food will eventually come after seeing the lever. Throughout this process, neuronal activity is measured through immunohistochemistry and protein immunofluorescence combined with intronic fluorescence in situ hybridization (PICIFISH). These are methods of staining and amplifying the c-fos MRNA signal through the application of multiple antibodies and blocking serums, which allows us to see the varying levels of c-fos mRNA, a marker for neuronal activity, in various rat brain slices. After these processes are complete, the brain slices are viewed under the microscope, helping us develop an understanding of how much c-fos mRNA was created. By understanding and inspecting the levels of c-fos mRNA expression and neuronal structure of the rats, we hope to develop an understanding of the neurobiology that correlates with addiction and PTSD based on the varying levels of c-fos expression in the distinct types of rats.