Reward system in the context of "Parental investment"

Euphoria (/juːˈfɔːriə/ yoo-FOR-ee-ə) is the experience (or affect) of pleasure or excitement and intense feelings of well-being and happiness. Certain natural rewards and social activities, such as aerobic exercise, laughter, listening to or making music and dancing, can induce a state of euphoria. Euphoria is also a symptom of certain neurological or neuropsychiatric disorders, such as mania. Romantic love and components of the human sexual response cycle are also associated with the induction of euphoria. Certain drugs, many of which are addictive, can cause euphoria, which at least partially motivates their recreational use.

Hedonic hotspots – i.e., the pleasure centers of the brain – are functionally linked. Activation of one hotspot results in the recruitment of the others. Inhibition of one hotspot results in the blunting of the effects of activating another hotspot. Therefore, the simultaneous activation of every hedonic hotspot within the reward system is believed to be necessary for generating the sensation of an intense euphoria.

The phrase "carrot and stick" is a metaphor for when two different methods of incentivisation are simultaneously employed; the "carrot", referring to the promising and giving of desired rewards in exchange for cooperation; and the "stick", referring to the threat of undesired consequences in response to noncompliance or to compel compliance. In politics, the terms are respectively analogous to the concepts of soft and hard power. A political example of a carrot may be the promise of foreign aid or military support, while the stick may be the threat of military action or imposition of economic sanctions. In religion, the concept of Heaven is considered the "carrot" while Hell is the corresponding "stick."

Substance dependence, also known as drug dependence, is a biopsychological situation whereby an individual's functionality is dependent on the necessitated re-consumption of a psychoactive substance because of an adaptive state that has developed within the individual from psychoactive substance consumption that results in the experience of withdrawal and that necessitates the re-consumption of the drug. A drug addiction, a distinct concept from substance dependence, is defined as compulsive, out-of-control drug use, despite negative consequences. An addictive drug is a drug which is both rewarding and reinforcing. ΔFosB, a gene transcription factor, is now known to be a critical component and common factor in the development of virtually all forms of behavioral and drug addictions, but not dependence.

The International Classification of Diseases classifies substance dependence as a mental and behavioural disorder. In the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) (released in 2013), substance abuse and substance dependence were eliminated and replaced with the single diagnosis of substance use disorders. This was done because "the tolerance and withdrawal that previously defined dependence are actually very normal responses to prescribed medications that affect the central nervous system and do not necessarily indicate the presence of an addiction."

Addiction is a neuropsychological disorder characterized by a persistent and intense urge to use a drug or engage in a behavior that produces natural reward, despite substantial harm and other negative consequences. Repetitive drug use can alter brain function in synapses similar to natural rewards like food or falling in love in ways that perpetuate craving and weakens self-control for people with pre-existing vulnerabilities. This phenomenon – drugs reshaping brain function – has led to an understanding of addiction as a brain disorder with a complex variety of psychosocial as well as neurobiological factors that are implicated in the development of addiction. While mice given cocaine showed the compulsive and involuntary nature of addiction, for humans this is more complex, related to behavior or personality traits.

Classic signs of addiction include compulsive engagement in rewarding stimuli, preoccupation with substances or behavior, and continued use despite negative consequences. Habits and patterns associated with addiction are typically characterized by immediate gratification (short-term reward), coupled with delayed deleterious effects (long-term costs).

A food addiction or eating addiction is any behavioral addiction characterized primarily by the compulsive consumption of palatable and hyperpalatable food items, and potentially also sugar-sweetened beverages (SSBs). Such foods often have high sugar, fat, and salt contents (HFSS), and markedly activate the reward system in humans and other animals. Those with eating addictions often overconsume such foods despite the adverse consequences (such as excess weight gain, diabetes, and heart disease) associated with their overconsumption.

Psychological dependence has also been observed, with the occurrence of withdrawal symptoms when substituting foods low in sugar and fat. Professionals address psychological dependence by providing behavior therapy and through administering the YFAS (Yale Food Addiction Scale) questionnaire, a diagnostic criterion of substance dependence.

A bounty is a payment or reward of money to locate, capture or kill an outlaw or a wanted person. Two modern examples of bounties are the ones placed for the capture of Saddam Hussein and his sons by the United States government and Microsoft's bounty for computer virus creators. Those who make a living by pursuing bounties are known as bounty hunters.

Bounties have also been granted for other actions, such as exports under mercantilism.

Behavioral addiction, process addiction, or non-substance-related disorder is a form of addiction that involves a compulsion to engage in a rewarding non-substance-related behavior – sometimes called a natural reward – despite any negative consequences to the person's physical, mental, social or financial well-being. In the brain's reward system, a gene transcription factor known as ΔFosB has been identified as a necessary common factor involved in both behavioral and drug addictions, which are associated with the same set of neural adaptations.

Addiction canonically refers to substance abuse; however, the term's connotation has been expanded to include behaviors that may lead to a reward (such as gambling, eating, or shopping) since the 1990s. Still, the framework to diagnose and categorize behavioral addiction is a controversial topic in the psychopathology field.