The<unk>  (the mesocorticolimbic circuit) is a group of neural structures responsible for incentive salience (i.e., "wanting"; desire or craving for a<unk>  and motivation), associative learning (primarily positive reinforcement and classical conditioning), and positively-valenced emotions, particularly ones involving pleasure as a core component (e.g., joy, euphoria and ecstasy).<unk>  is the attractive and motivational property of a stimulus that induces appetitive behavior, also known as approach behavior, and consummatory behavior. A<unk> ing stimulus has been described as "any stimulus, object, event, activity, or situation that has the potential to make us approach and consume it is by definition a<unk> ". In operant conditioning,<unk> ing stimuli function as positive reinforcers; however, the converse statement also holds true: positive reinforcers are<unk> ing. The<unk>  motivates animals to approach stimuli or engage in behaviour that increases fitness (sex, energy-dense foods, etc.). Survival for most animal species depends upon maximizing contact with beneficial stimuli and minimizing contact with harmful stimuli.<unk>  cognition serves to increase the likelihood of survival and reproduction by causing associative learning, eliciting approach and consummatory behavior, and triggering positively-valenced emotions. Thus,<unk>  is a mechanism that evolved to help increase the adaptive fitness of animals. In drug addiction, certain substances over-activate the<unk>  circuit, leading to compulsive substance-seeking behavior resulting from synaptic plasticity in the circuit. Primary<unk> s are a class of<unk> ing stimuli which facilitate the survival of one's self and offspring, and they include homeostatic (e.g., palatable food) and reproductive (e.g., sexual contact and parental investment)<unk> s. Intrinsic<unk> s are unconditioned<unk> s that are attractive and motivate behavior because they are inherently pleasurable. Extrinsic<unk> s (e.g., money or seeing one's favorite sports team winning a game) are conditioned<unk> s that are attractive and motivate behavior but are not inherently pleasurable. Extrinsic<unk> s derive their motivational value as a result of a learned association (i.e., conditioning) with intrinsic<unk> s. Extrinsic<unk> s may also elicit pleasure (e.g., euphoria from winning a lot of money in a lottery) after being classically conditioned with intrinsic<unk> s.
Reward system
Social narrative
Outline of health
The Soul of Medicine
Bobath concept
Source control 
Personal narrative
Drug policy