Reward and the serotonergic system

• Published in: Neuroscience Vol. 166; no. 4; pp. 1023 - 1035
• Main Authors: Kranz, G.S., Kasper, S., Lanzenberger, R.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier Ltd 14.04.2010; Elsevier
• Subjects: Animals; Biological and medical sciences; Cognition - physiology; Emotions - physiology; Fundamental and applied biological sciences. Psychology; hedonia; Humans; intracranial self-stimulation; Models, Animal; motivation; Neural Pathways - anatomy & histology; Neural Pathways - metabolism; Neurology; Neurons - metabolism; pleasure; Pleasure - physiology; Primates; Raphe Nuclei - anatomy & histology; Raphe Nuclei - metabolism; Reward; Self Stimulation - physiology; serotonin; Serotonin - metabolism; Synaptic Transmission - physiology; Vertebrates: nervous system and sense organs; reward; ACC; DRN; VTA; pleasure; motivation; hedonia; 8-OH DPAT; MFB; MRN; OFC; intracranial self-stimulation; BP; SSRI; serotonin; NAcc; pCPA; ICSS; SN; 5-HT; PET; median raphe nucleus; 8-Hydroxy- N, N-dipropyl-2-aminotetralin; p-chlorophenylalanine; binding potential; selective serotonin reuptake inhibitor; orbitofrontal cortex; anterior cingulate cortex; substantia nigra; nucleus accumbens; dorsal raphe nucleus; medial forebrain bundle; ventral tegmental area; positron emission tomography; Serotonin; Neurotransmitter; Self stimulation; Reward
• ISSN: 0306-4522; 1873-7544; 1873-7544
• DOI: 10.1016/j.neuroscience.2010.01.036

Anhedonia, as a failure to experience rewarding stimuli, is a key characteristic of many psychiatric disorders including depression and schizophrenia. Investigations on the neurobiological correlates of reward and hedonia/anhedonia have been a growing subject of research demonstrating several neuromodulators to mediate different aspects of reward processing. Whereas the majority of research on reward mainly focused on the dopamine and opioid systems, a serotonergic mechanism has been neglected. However, recent promising results strengthen the pivotal role of serotonin in reward processing. Evidence includes electrophysical and pharmacological as well as genetic and imaging studies. Primate research using single-unit recording of neurons within the dorsal raphe nucleus argues for a serotonergic mediation of reward value, whereas studies using intracranial self-stimulation point to an important contribution of serotonin in modulating motivational aspects of rewarding brain stimulation. Pharmacological studies using agonists and antagonists of serotonergic receptor subtypes and approaches investigating an increase or decrease of the extracellular level of serotonin offer strong evidence for a serotonergic mediation, ranging from aversion to pleasure. This review provides an argument for serotonin as a fundamental mediator of emotional, motivational and cognitive aspects of reward representation, which makes it possibly as important as dopamine for reward processing.