Stratiatal contribution to outcome-dependent action control / Sofia de Mascarenhas dos Reis de Castro e Almeida ; orient. Rita Teodoro, Ingo Willuhn
Stratiatal contribution to outcome-dependent action control / Sofia de Mascarenhas dos Reis de Castro e Almeida ; orient. Rita Teodoro, Ingo Willuhn . - Lisboa : NOVA Medical School, 2021 . - 58 p. : il. . -
Our everyday actions depend on adaptations to a given situation in order to achieve desirable outcomes. However, action control (i.e., action initiation and suppression), is biased to the outcome we aim to achieve – receive a reward or avoid a punishment. Rewards tend to activate actions (go), while punishments tend to suppress actions (no-go). This process, known as Pavlovian bias, is impaired in several psychiatric disorders such as impulsive control disorder and depression, resulting in excessive tendency to initiate actions in rewarding conditions and accentuated action suppression in punishment conditions, respectively. Patient studies have associated activity in the striatum, the input nucleus of the basal ganglia, in outcome-dependent action control. Studies with rodents have additionally shown that action control is facilitated by two subpopulations of striatal medium spiny neurons (MSN), dopamine 1 and dopamine 2 receptor-expressing MSN’s. This project attempted to understand how outcome-dependent action control is encoded by these neuronal populations, particularly in different striatal subcompartments. To achieve this, we used implantable miniaturized fluorescent microscopes to perform 1-photon calcium imaging. However, GCaMP expression in rats’ striatum is not trivial which has hampered the course of the project. Nonetheless, we optimized both surgical and behavioral procedures, which facilitates the future direction of this project. In addition, we combined and optimized several adeno-associated viruses that allowed us to measure genetically defined neuronal populations in striatal sub regions in rats, for the first time. Our novel viral approach will be useful for future studies combining complex behaviors with basal ganglia activity. These findings might help projects studying impairments in Pavlovian bias, as seen in several psychiatric disorders. Biomedical Research
Academic Dissertation
616
Stratiatal contribution to outcome-dependent action control / Sofia de Mascarenhas dos Reis de Castro e Almeida ; orient. Rita Teodoro, Ingo Willuhn . - Lisboa : NOVA Medical School, 2021 . - 58 p. : il. . -
Our everyday actions depend on adaptations to a given situation in order to achieve desirable outcomes. However, action control (i.e., action initiation and suppression), is biased to the outcome we aim to achieve – receive a reward or avoid a punishment. Rewards tend to activate actions (go), while punishments tend to suppress actions (no-go). This process, known as Pavlovian bias, is impaired in several psychiatric disorders such as impulsive control disorder and depression, resulting in excessive tendency to initiate actions in rewarding conditions and accentuated action suppression in punishment conditions, respectively. Patient studies have associated activity in the striatum, the input nucleus of the basal ganglia, in outcome-dependent action control. Studies with rodents have additionally shown that action control is facilitated by two subpopulations of striatal medium spiny neurons (MSN), dopamine 1 and dopamine 2 receptor-expressing MSN’s. This project attempted to understand how outcome-dependent action control is encoded by these neuronal populations, particularly in different striatal subcompartments. To achieve this, we used implantable miniaturized fluorescent microscopes to perform 1-photon calcium imaging. However, GCaMP expression in rats’ striatum is not trivial which has hampered the course of the project. Nonetheless, we optimized both surgical and behavioral procedures, which facilitates the future direction of this project. In addition, we combined and optimized several adeno-associated viruses that allowed us to measure genetically defined neuronal populations in striatal sub regions in rats, for the first time. Our novel viral approach will be useful for future studies combining complex behaviors with basal ganglia activity. These findings might help projects studying impairments in Pavlovian bias, as seen in several psychiatric disorders. Biomedical Research
Academic Dissertation
616
