The ups and downs of dopamine. Studies of striatal dopamine release in behaving rats during appetitive and aversive conditioning.

TY - THES

T1 - The ups and downs of dopamine.

T2 - Studies of striatal dopamine release in behaving rats during appetitive and aversive conditioning.

AU - Goedhoop, Jessica

PY - 2024

Y1 - 2024

N2 - Dopamine has been hypothesized to be a key player for the control of different types of behavior. Dopamine is synthesized by midbrain dopamine neurons of which the main output region is the striatum, a brain region which can be subdivided into different functional regions. Striatal dopamine has been hypothesized to have different functions; the encoding of reward-prediction errors, motivation, movement and several others depending on the striatal subregion. However, whether dopamine truly has all these different functions and if so, how these different signals are translated into the concentration of extracellular dopamine is still an active point of debate. In this thesis, we aimed to study the different signals conveyed by dopamine release and its involvement in the control of behavior by using fast-scan cyclic voltammetry to measure extracellular dopamine in different functional striatal territories in behaving rats. We found evidence for aversive prediction errors in the nucleus accumbens in rats that were exposed to aversive white noise. We looked at dopamine dynamics in 6 different functional regions of the striatum during different behaviors and found uniform dopamine signaling, but differences in amount of dopamine release. We compared dopamine signaling in the ventromedial striatum during Pavlovian and operant conditioning and observed dopamine ramps while rats anticipated the execution of an operant action. And finally, our results showed dorsomedial striatum dopamine release related to habitual reward seeking behavior. Together our findings provide new insights into the encoding of both the ups and downs of dopamine in the striatum.

AB - Dopamine has been hypothesized to be a key player for the control of different types of behavior. Dopamine is synthesized by midbrain dopamine neurons of which the main output region is the striatum, a brain region which can be subdivided into different functional regions. Striatal dopamine has been hypothesized to have different functions; the encoding of reward-prediction errors, motivation, movement and several others depending on the striatal subregion. However, whether dopamine truly has all these different functions and if so, how these different signals are translated into the concentration of extracellular dopamine is still an active point of debate. In this thesis, we aimed to study the different signals conveyed by dopamine release and its involvement in the control of behavior by using fast-scan cyclic voltammetry to measure extracellular dopamine in different functional striatal territories in behaving rats. We found evidence for aversive prediction errors in the nucleus accumbens in rats that were exposed to aversive white noise. We looked at dopamine dynamics in 6 different functional regions of the striatum during different behaviors and found uniform dopamine signaling, but differences in amount of dopamine release. We compared dopamine signaling in the ventromedial striatum during Pavlovian and operant conditioning and observed dopamine ramps while rats anticipated the execution of an operant action. And finally, our results showed dorsomedial striatum dopamine release related to habitual reward seeking behavior. Together our findings provide new insights into the encoding of both the ups and downs of dopamine in the striatum.

M3 - PhD thesis

ER -