Role of brain dopamine in food reward and reinforcement

Abstract

The ability of food to establish and maintain response habits and conditioned preferences depends largely on the function of brain dopamine systems. While dopaminergic transmission in the nucleus accumbens appears sufficient for some forms of reward, the role of dopamine in food reward does not appear to be restricted to this region. Dopamine plays an important role in both the ability to energize feeding and to reinforce food-seeking behaviour; the role in energizing feeding is secondary to the prerequisite role in reinforcement. Dopaminergic activation is triggered by the auditory and visual as well as the tactile, olfactory, and gustatory stimuli of foods. While dopamine plays a central role in the feeding and food-seeking of normal animals, some food rewarded learning can be seen in genetically engineered dopamine-deficient mice.

Effect of cognitive enrichment on behavior, mucosal immunity and upper respiratory disease of shelter cats rated as frustrated on arrival

“…Rewarding activities cause dopaminergic neuron activation (DA) and thus increase the production of dopamine associated with a feeling of pleasure (Arias-Carrión and Pŏppel, 2007). Rewards, which can be anything that the animal wants and attains, increase DA (Wise, 2006). As there are dopamine receptors in the gastrointestinal tract, where IgA is secreted (Kullmann et al, 1983), and that DA increases blood flow to the mucosa causing mucosal vasodilatation by up to 400% (Sjövall et al, 1984), increased dopamine may have contributed to the stimulation of IgA secretion.…”

Affective neuroscience of pleasure: reward in humans and animals

“…This challenge is difficult because a rewarding stimulus or event will elicit many or all of these reward components simultaneously and so activate many brain systems at the same time. Careful studies are needed to tease apart whether activity in a particular brain region belongs most to the 'liking', 'wanting', or learning sub-components of reward and to understand how components are assembled by larger limbic circuits into an integrated reward system (Baldo and Kelley 2007;Balleine and Killcross 2006;Beaver et al 2006;Burke et al 2008;Di Chiara and Bassareo 2007;Evans et al 2006;Everitt and Robbins 2005;Izard 2007; Koob and Le Moal 2006;Kringelbach 2004;Leyton et al 2005;Panksepp 2007;Salamone et al 2007;Schultz 2006;Volkow et al 2006;Wise 2006). …”

Accumbens dopamine-acetylcholine balance in approach and avoidance

“…DA depletion with 6-hydroxy-dopamine suggests that DA is needed for instrumental work output [19]. DA antagonists briefly increase operant responding for food, which then gradually declines, suggesting a loss of reward and not simply loss of motivation or motor impairment [20,21]. Ahn & Phillips [22] use a random interval schedule of food reinforcement and suggest that reinforcement uncertainty maintains high DA levels in the medial NAc over many days of training.…”