Reward Pathways in Brain The New Science of Addiction: Genetics and the Brain

characterized by changes in the brain

which result in a compulsive desire to use a drug. A combination of many factors including genetics, environment and behavior influence a person's addiction risk, making it an incredibly complicated disease. The new science of addiction considers all of these factors - from biology to family - to unravel the complexities of the addicted brain.

Natural Reward Pathways Exist in the Brain
Natural Reward Pathways Exist in the Brain

The reward pathway is responsible for driving our feelings of motivation, reward and behavior.

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Make a Mad, Mad, Mad Neuron
Crossing the Divide: How Neurons Talk to Each Other
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The Other Brain Cells
Meth-Addicted Brain Cell Compared to a Normal Brain Cell
Drugs Alter the Brain's Reward Pathway
Drugs Alter the Brain's Reward Pathway

Drugs work over time to change the reward pathway and affect the entire brain, resulting in addiction.

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Drugs of Abuse
Mouse Party
Cerebral Commando
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Beyond the Reward Pathway
Drug Delivery Methods
How Drugs Can Kill
Brain Imaging Technologies

What it means to be "hard-wired." Shown above, a cell from a meth-addicted brain (right) differs in structure from a normal brain cell (left). Taking meth causes long-lasting brain cell changes.

Pedigree Chart
Genetics Is An Important Factor In Addiction
Genetics Is An Important Factor In Addiction

Genetic susceptibility to addiction is the result of the interaction of many genes.

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PI: Pedigree Investigator, On the Case of Nicotine Addiction
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Discovering Addiction Genes Using the Candidate Gene Approach
Mice are Good Model Organisms for Addiction Research
A girl smoking a cigarette

Ninety percent of smokers start at or before age 18. The vast majority of adults who are addicted to nicotine began smoking during adolescence.

Timing and Circumstances Influence Addiction
Timing and Circumstances Influence Addiction

If you use drugs when you are an adolescent, you are more likely to develop lifetime addiction. An individual's social environment also influences addiction risk.

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Environmental Risk Factors For Addiction
Coca Leaves

A Peruvian woman sells coca leaves (from which cocaine is derived). Coca is chewed as a mild daily stimulant and smoked in religious ceremonies. Should certain cultures be permitted to use an illegal drug? If so, how is that use regulated?

Challenges and Issues in Addiction
Challenges and Issues in Addiction

Addiction impacts society with many ethical, legal and social issues.

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Addiction Treatments Past and Present
Cannabis in the Clinic? The Medical Marijuana Debate
Mental Illness: The Challenge of Dual Diagnosis
Ritalin and Cocaine: The Connection and the Controversy
Additional Resources
Additional Resources

Links to information about the topics discussed here and more.

Credits
Credits
National Institute on Drug Abuse

Supported by a Science Education Drug Abuse Partnership Award (SEDAPA), from The National Institute on Drug Abuse, National Institutes of Health. The contents provided here are solely the responsibility of the authors and do not necessarily represent the official views of NCRR or NIH.
Grant Number: 1 R25 DA 15461