The Mechanism of Addiction
Addiction is a chronic, relapsing disease affecting the brain’s reward, motivation, and related systems. People struggling with addiction are unable to control their actions or make rational decisions about their behaviour, even in the face of negative consequences.
Compounds and experiences with addictive potential activate the brain’s reward circuitry. These triggers are also called reinforcers because the pleasurable feeling we get from them makes us more likely to engage in them again. Both alcohol and illicit drugs are powerful reinforcers, and cause the release of the neurotransmitter dopamine in the brain’s reward system. Repeated activation by these compounds changes the brain’s reward system structurally and chemically, and produces behaviours like bingeing,escalating use, and symptoms of withdrawal when the drugs are taken away.
Addiction is a process based in altered functioning of the reward and motivation systems of the brain. It can manifest in many ways, but historically addictions fall under two categories.
This includes dependence on any of the following:
- Street drugs
- Prescription drugs
Behavioural or Process AddictionS
Although less well studied, many behaviours appear to have reinforcing properties, and may involve excesses related to:
- The Internet
- Video Games
Multiple Addictions and Co-morbid Factors
Science shows that substance and behavioural addictions can occur within the same individual and that multiple variants of substance or process addiction can be expressed at the same time. Thus, people can have multiple addictions with each addition being active to differing degrees of severity. Additionally, depression and anxiety frequently accompany addiction as co-morbid factors.