How Drug and Alcohol Addiction Hijacks Your Brain
The reward center in the brain is an area that is activated by the presence of basic needs such as food and sex and reacts to these needs by releasing a surge of dopamine. Dopamine is a neurotransmitter that produces pleasant and satisfying feelings of well-being. drug and alcohol addiction
The reward system, however, also responds to psychoactive substances that can initiate a greater release of dopamine than normally produced by basic needs.
This feel-good center of the brain, however, isn’t the only network impacted by substance use. In fact, recent research has shown that addiction also affects five other major areas of the brain, including those involved with habit, salience, memory, self-direction and executive processes.
For the research, scientists analyzed more than 100 studies and reviews, each one focusing on drug addiction. They examined the results of a commonly-used brain scan known as functional magnetic resonance imaging (fMRI).
As it turned out, most (more than half) of the studies conducted concentrated on the impact of drug abuse on the brain’s reward center. But they also found that the effects of substances are distributed among five other networks.
For instance, the center of the brain that involves memory was largely ignored in the research analyzed. This finding is unfortunate because some studies indicated that among people with SUDs, stress shifts from the person’s learning and memory processes away from the memory network to the habit center of the brain. The habit network functions to drive automatic responses such as seeking out and using substances.
Another neglected network controls self-direction, which involves self-awareness and self-reflection. Among those with SUDs, this network has been linked to an increase in cravings.
And there are still two other networks that are affected by SUDs – salience and executive functioning. The executive center usually carries the responsibility of goal maintenance and execution, but when drugs impact this network, it can result in impulsivity, or an impaired ability to inhibit actions.
The salience network identifies critical cues (referred to as “highly relevant stimuli” in a person’s surroundings and directs the individual’s attention accordingly. For those who suffer from drug and alcohol addiction, that attention is redirected to psychoactive substances, thus promoting cravings and drug-seeking behavior.
Researchers hope that more studies will focus on whether some people have pre-existing abnormal brain activity in these networks and if this activity gets further complicated by drug use. If this is the case, it may one day be possible to “diagnose” those who are the most susceptible to addiction and intervene before it’s too late.
Fortunately, activity in four of the six networks (executive, memory, reward, and salience) can return to normal functioning following cessation of drug use. The authors also noted, however, that some small regions of the brain (such as the amygdala) can’t be studied yet because current technology is not capable of identifying strong signals in brain scans from these areas.