Drug addiction

Drug addiction, or substance dependence is the compulsive use of drugs, to the point where the user has no effective choice but to continue use. This phenomenon has occurred to some degree throughout recorded history (see "opium"), though modern agricultural practices, improvements in access to drugs, and advancements in biochemistry have exacerbated the problem significantly in the 20th century with the introduction of purified forms of active biological agents, and with the synthesis of hitherto unknown substances, such as methamphetamine and gamma-hydroxybutyrate (GHB). While "addiction" has been replaced by "dependency" as a clinical term, the terms are used interchangeably here.

Evolutionary psychology view of addiction

It is obvious that genes for addiction would not be

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directly selected. Since evolution theory claims that

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every physical and behavioral trait is a direct or

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side effect of selection, then the capacity to be

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addicted to drugs must be a side effect of something

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that was selected.

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A number of writers including Keith Henson

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http://human-nature.com/nibbs/02/cults.html have

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suggested that the capacity to be addicted to drugs is

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a side effect of social attention rewards. It is easy

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to understand how sensitivity to social rewards would

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evolve in social primates. For example, Jane Goodall's observation that chimpanzees who hunt get

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additional mating opportunities. The proposed evolved

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mechanism for social rewards is that attention causes

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the release of endorphins and dopamine into the

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brain's reward circuits.

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It is proposed that addictive drugs activate brain

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reward circuits that are normally activated by attention,

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without the need to kill a large, dangerous animal and

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drag it back to camp (or modern equivalents.)

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