There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.
Abstract
Drugs of abuse are very powerful reinforcers, and even in conditions of limited access
(where the organism is not dependent) these drugs will motivate high rates of operant
responding. This presumed hedonic property and the drugs' neuropharmacological specificity
provide a means of studying the neuropharmacology and neuroanatomy of brain reward.
Three major brain systems appear to be involved in drug reward--dopamine, opioid and
GABA. Evidence suggests a midbrain-forebrain-extrapyramidal circuit with its focus
in the nucleus accumbens. Data implicating dopamine and opioid systems in indirect
sympathomimetic and opiate reward include critical elements in both the nucleus accumbens
and ventral tegmental areas. Ethanol reward appears to depend on an interaction with
the GABAA receptor complex but may also involve common elements such as dopamine and
opioid peptides in this midbrain-forebrain-extrapyramidal circuit. These results suggest
that brain reward systems have a multidetermined neuropharmacological basis that may
involve some common neuroanatomical elements.