Arbitration between model-free and model-based control is not affected by transient changes in tonic serotonin levels

Publikation: Beitrag in FachzeitschriftForschungsartikelBeigetragenBegutachtung

Beitragende

Abstract

BACKGROUND: Serotonin has been suggested to modulate decision-making by influencing the arbitration between model-based and model-free control. Disruptions in these control mechanisms are involved in mental disorders such as drug dependence or obsessive-compulsive disorder. While previous reports indicate that lower brain serotonin levels reduce model-based control, it remains unknown whether increases in serotonergic availability might thus increase model-based control. Moreover, the mediating neural mechanisms have not been studied yet.

AIM: The first aim of this study was to investigate whether increased/decreased tonic serotonin levels affect the arbitration between model-free and model-based control. Second, we aimed to identify the underlying neural processes.

METHODS: We employed a sequential two-stage Markov decision-task and measured brain responses during functional magnetic resonance imaging in 98 participants in a randomized, double-blind cross-over within-subject design. To investigate the influence of serotonin on the balance between model-free and model-based control, we used a tryptophan intervention with three intervention levels (loading, balanced, depletion). We hypothesized that model-based behaviour would increase with higher serotonin levels.

RESULTS: We found evidence that neither model-free nor model-based control were affected by changes in tonic serotonin levels. Furthermore, our tryptophan intervention did not elicit relevant changes in Blood-Oxygenation-Level Dependent activity.

Details

OriginalspracheEnglisch
Seiten (von - bis)178-187
Seitenumfang10
FachzeitschriftJournal of Psychopharmacology
Jahrgang38
Ausgabenummer2
Frühes Online-Datum27 Dez. 2023
PublikationsstatusVeröffentlicht - Feb. 2024
Peer-Review-StatusJa

Externe IDs

unpaywall 10.1177/02698811231216325
ORCID /0000-0001-5398-5569/work/150329560
Scopus 85181192054

Schlagworte

Schlagwörter

  • Brain, Cross-Over Studies, Double-Blind Method, Humans, Negotiating, Obsessive-Compulsive Disorder, Serotonin, Tryptophan

Bibliotheksschlagworte