Characterizing Dopaminergic Signaling in the Nucleus Accumbens Core Across Different Sign-tracking responses using Fiber Photometry

Authors

Daniela Garrod, Dartmouth CollegeFollow
Erica Townsend, Dartmouth CollegeFollow
Kyle S. Smith, Dartmouth CollegeFollow

Files

Student Class

2024

Student Affiliation

Senior Honors Thesis

First Advisor

Kyle S. Smith

First Advisor Department

Department of Psychological and Brain Sciences

Second Advisor

Katherine M. Nautiyal

Second Advisor Department

Department of Psychological and Brain Sciences

Description

Motivation is a fundamental force driving our everyday actions, yet the intricate neural pathways underlying it and the ways it manifests differently among individuals remain largely unknown. To assess this question, this study characterizes the role of dopamine (DA) signaling in the nucleus accumbens core (NAc) on individual differences in sign-tacking responses. Peak DA signaling during reward-predicted cue (CS+) onset was recorded through in-vivo fiber photometry on the last day of sign-tracking training, while the sign-tracking responses were measured through presses per minute (PPMs) and behavioral video scoring. Rats were then placed in an omission schedule where the persistence and vigor of sign-tracking responses were tested. Results indicate that DA release in the NAc at CS+ onset during sign-tracking training may not only attribute incentive value to a reward-predicting cue but also regulate how much we want to interact with it or want it. There are distinct correlations between DA signaling and sign-tracking behaviors during both sign tracking training and omission trials, suggesting that DA release at CS+ onset may serve a different function in these two paradigms. Overall, these findings attempt to understand the rich differences in motivated behavior, which could potentially be useful in the diagnosis and treatment of disorders like addiction and binge eating.

Publication Date

Spring 6-2024

Keywords

sign-tracking, nucleus accumbens, dopamine, addiction, motivation, behavior model

Disciplines

Behavioral Neurobiology | Systems Neuroscience

Dartmouth Digital Commons Citation

Garrod, Daniela; Townsend, Erica; and Smith, Kyle S., "Characterizing Dopaminergic Signaling in the Nucleus Accumbens Core Across Different Sign-tracking responses using Fiber Photometry" (2024). Wetterhahn Science Symposium Posters 2024. 14.
https://digitalcommons.dartmouth.edu/wetterhahn_2024/14