The neurotransmitter dopamine and its role in neurological diseases The biogenic catecholamine dopamine (DA) functions mainly as a neurohormone and neurotransmitter. It also functions as an intermediary step in the biosynthesis of norepinephrine and epinephrine, structurally similar catecholamines that serve as cell regulators and neurotransmitters in mammals. The neurotransmitter function of D...

Addiction is almost universally held to be characterized by a loss of control over drug-seeking and consuming behavior. But the actions of addicts, even of those who seem to want to abstain from drugs, seem to be guided by reasons. In this paper, I argue that we can explain this fact, consistent with continuing to maintain that addiction involves a loss of control, by understanding addiction as...

The ability to learn stimulus-reward associations on the basis of reward prediction errors critically depends on the mesolimbic dopaminergic system including the dopaminergic midbrain and the ventral striatum. It is known that healthy elderly and patients with Parkinson's disease are less proficient than healthy young adults in learning stimulus-reward contingencies, but it is unclear whether t...

VANDERBILT REVIEWS | NEUROSCIENCE VOLUME 1 | MAY 2009 | 17 ©2009 Vanderbilt Brain Institute. All rights reserved. Dopaminergic neurons originate mainly from two midbrain regions, the ventral tegmental area (VTA) and the substantia nigra pars compacta (SNc). SNc neurons project to the dorsal caudate nuclei of the striatum, forming the nigrostriatal pathway. The striatum participates in extrapyra...

Increases in mesolimbic dopamine transmission are observed when animals are treated with all known drugs of abuse, including cannabis, and to conditioned stimuli predicting their availability. In contrast, decreases in mesolimbic dopamine function are observed during drug withdrawal, including cannabis-withdrawal syndrome. Thus, despite general misconceptions that cannabis is unique from other ...

BACKGROUND Rearing rats in environmental enrichment alters psychostimulant-induced locomotor activity as well as neurotransmitter expression. Exposure to novelty and psychostimulants induces c-fos expression in neurons in the mesolimbic dopamine (DA) pathway. Here we investigated changes in the expression of the immediate early gene c-fos in the mesolimbic DA pathway of enriched, isolated, or s...

Evidence links dopamine release in the mid-brain to the pathophysiology of psychosis, addiction and reward. Repeated ingestion of refined carbohydrate may stimulate the same mesolimbic dopaminergic pathway, rewarding such eating behaviour and resulting in excessive food intake along with obesity. In this paper, we explore the role of dopamine in reward and psychosis, and discuss how reward path...

Mice experiencing repeated aggression develop a long-lasting aversion to social contact, which can be normalized by chronic, but not acute, administration of antidepressant. Using viral-mediated, mesolimbic dopamine pathway-specific knockdown of brain-derived neurotrophic factor (BDNF), we showed that BDNF is required for the development of this experience-dependent social aversion. Gene profil...