Addiction is a condition in which a person engages in the use of a substance or in a behavior for which the rewarding effects provide a compelling incentive to repeatedly pursue the behavior despite detrimental consequences. Addiction may involve the use of substances such as alcohol, inhalants, opioids, cocaine, nicotine, and others, or behaviors such as gambling.
There is scientific evidence that the addictive behaviors share key neurobiological features: They intensely involve brain pathways of reward and reinforcement, affecting motivation, which involve the neurotransmitter dopamine.
And, in keeping with other highly motivated states, they lead to the pruning of synapses in the prefrontal cortex, home of the brain's highest functions, so that attention is highly focused on cues related to the target substance or activity. It is important to know that the brain changes are reversible after the substance use or behavior is discontinued.
Both substance use disorders and gambling behaviors have an increased likelihood of being accompanied by mental health conditions such as depression and anxiety or other pre-existing problems. Substance use and gambling disorders not only engage the same brain mechanisms, they respond to many of the same approaches to treatment.
Complex conditions that affect reward, reinforcement, motivation, and memory systems of the brain, substance use and gambling disorders are characterized by impaired control over usage; social impairment, involving disruption of everyday activities and relationships; and may involve craving. Continuing use is typically harmful to relationships and work or school obligations.
Another distinguishing feature is that individuals may continue the activity despite physical or psychological harm incurred or exacerbated by use. And typically, tolerance to the substance increases, as the body adapts to its presence.
Because addiction affects the brain’s executive functions, centered in the prefrontal cortex, individuals who develop an addiction may not be aware that their behavior is causing problems for themselves and others. Over time, pursuit of the pleasurable effects of the substance or behavior may dominate an individual’s activities.
Although all addictions have the capacity to induce a sense of hopelessness and feelings of failure, as well as shame and guilt, research documents that recovery is the rule rather than the exception, and that there are many routes to recovery. Individuals can achieve improved physical, psychological, and social functioning on their own—so-called natural recovery.
Others prefer the support of community or peer-based networks. Still others opt for clinical-based recovery through the services of credentialed professionals.
The road to recovery is seldom straight: Relapse, or recurrence of substance use, is common—but definitely not the end of the road. For those who achieve remission of the disorder for five years, scientists report, the likelihood of relapse is no greater than that among the general population. Neuroscientists report that synaptic density is gradually restored.