A new essay on drug addiction highlights how drugs hijack a user's brain, basically changing the way it works.
Dr. Nora Volkow, director of the National Institute on Drug Abuse, describes how addiction rewires the brain's reward systems to impair normal thinking and behavior.
People's ability to successfully identify, seek, and obtain what is important to them (but also avoid what's undesirable) at a particular point in time is crucial for their well-being. That which motivates us toward obtaining certain goals plays a key role in how successfully we navigate complex social environments. The sinister nature of addiction is that the very neurobiological systems underpinning this process become dysfunctional, hijacked by a user's drug (or drugs) of choice.
Other research shows that addiction targets more than the reward system of the brain. Imaging studies show that the brain's cognitive systems in the prefrontal cortex area are disrupted by drug addiction.
For example, damage to ventral areas of this brain region can interfere with the ability of a person to accurately distinguish right from wrong in a socially acceptable manner, which can lead to socially inappropriate behaviors. . . Because the functions of these brain regions are also impaired in addicted individuals, this could explain an addict's inability to accurately steer their behaviors in appropriate directions despite having access to the required knowledge."
The essay is published in a special issue of the journal Neuron.