Das menschliche Belohnungssystem

Zusammenfassung

Belohnungen, oder allgemeiner positive Verstärkung, beeinflussen unser tägliches Leben in hohem Maße. Sie stellen Handlungsanreize und Motivatoren dar, und eine angemessene Reaktion auf lohnende Anreize ist eine wichtige Voraussetzung für Entscheidungsfindung und zielgerichtetes, effektives Verhalten. Die funktionelle Bildgebung hat in jüngster Zeit viel zu einem besseren Verständnis beigetragen, wie Belohnungen im menschlichen Gehirn verarbeitet werden. Befunde aus der tierexperimentellen Forschung wurden bestätigt und differenziert und neue Erkenntnisse zu Motivation und Lernvorgängen im Zusammenhang mit Belohnungen gewonnen. Für die wichtigsten beteiligten Strukturen, das ventrale Striatum, den orbitofrontalen Kortex und die Amygdala, wurden differenzierte Funktionen herausgearbeitet. Die so gewonnenen Erkenntnisse über das mesolimbisch-mesokortikale Dopaminsystem, das auf diese Regionen einwirkt, können nicht nur helfen, Reaktionen auf Belohnungsreize besser zu verstehen, sondern auch helfen, die Pathophysiologie von Suchterkrankungen, der Parkinson-Krankheit und Schizophrenie aufzuklären.

Summary

Rewards and positive reinforcement highly influence our daily life. An adequate reaction to incentive stimuli is an important prerequisite for decision-making and goal oriented, effective behaviour. Functional imaging recently gave new insights how rewards are processed in the human brain. Findings from animal studies were replicated and differentiated providing a new understanding of motivation and learning in the context of rewards. Differential functions were found for the most important structures involved, the ventral striatum, the orbitofrontal cortex and the amygdala. But knowledge about the mesolimbic-mesocortical dopaminergic system that interconnects the brain regions of the reward system can also help to develop a better understanding of the pathophysiology of drug abuse, Parkinson’s disease and schizophrenia.

Schlüsselwörter

Belohnungssystem - Dopamin - Nucleus accumbens - Schizophrenie

Keywords

Reward system - dopamine - nucleus accumbens - schizophrenia

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