ADC 655 Module 5 Neuroimaging in Addiction Example

Pictures of the Addicted Brain: What Neuroimaging Shows and What It Does Not

Student Name

Psychology and Addiction Studies Program, Aspen University

ADC 655: Neurobiology of Addiction

Instructor Name

Month Day, Year

Pictures of the Addicted Brain: What Neuroimaging Shows and What It Does Not

After a group session on the addiction cycle at the Colorado Springs program these papers follow, Marcus showed Nadia an image on his phone: two brain scans side by side, one bright, one dim, labeled "normal brain" and "addicted brain." "Is mine like that?" he asked. "Is it ruined?" Like the program, Marcus and Nadia are invented. What follows reviews what neuroimaging has shown and how Nadia might answer.

Imaging Methods

Dopamine Receptors and Frontal Function

Volkow et al. (1993) used positron emission tomography to measure dopamine D2 receptor availability in the striatum of people who had used cocaine heavily, studied after detoxification, and of people who had not. The cocaine users had lower D2 receptor availability, and the reduction persisted for months after they stopped using. Lower receptor availability was associated with lower metabolic activity in frontal regions, including the orbitofrontal cortex and the cingulate gyrus, areas involved in evaluating rewards and controlling behavior. The authors proposed that reduced dopamine signaling and frontal dysfunction together might contribute to the compulsive drug taking seen in addiction.

Craving in the Brain

Childress et al. (1999) studied what happens in the brain during craving. Using positron emission tomography to measure blood flow, they showed people who used cocaine and people who did not videos of cocaine-related scenes and of neutral scenes. In the cocaine users, the drug-related videos produced craving and increased activity in limbic regions, including the amygdala and the anterior cingulate. People without a cocaine history showed no such response. The study linked a subjective experience, craving, to activity in brain regions involved in emotion and motivation.

The Frontal Cortex

Goldstein and Volkow (2002) reviewed imaging evidence for frontal cortex involvement in addiction. They described a pattern: during intoxication and craving, frontal regions such as the orbitofrontal cortex and anterior cingulate were often more active, while during withdrawal and longer abstinence they were less active than in people without addiction. They proposed that frontal regions, which normally weigh rewards and inhibit unwanted actions, are disrupted in addiction in ways that increase the value attached to drugs and weaken control, contributing to compulsive use. They also noted that some frontal changes may precede drug use and increase vulnerability.

Recovery in the Scans

Later imaging studies have followed people over time in abstinence. Some changes, including reduced dopamine receptor availability and lower frontal metabolism, appear to recover partly over months without drugs, though recovery varies and may be incomplete. These findings matter to clients: the brain that imaging captures early in treatment is not the brain they will have a year later. Recovery is a biological process as well as a psychological one.

What Imaging Cannot Show

Imaging findings have limits. They describe average differences between groups; many individuals in each group overlap with the other. Most studies compare people at one point in time, so they cannot always show whether differences caused addiction or resulted from it. Images in popular media often exaggerate differences with color choices. And some changes, such as reduced dopamine receptors, appear to recover partly with sustained abstinence, while others may persist longer.

The Difference Between Groups and a Person

Imaging research usually reports that, on average, a group of people with addiction differs from a group without it. Individuals vary widely within each group, so many people with addiction have scans that look like those of people without it, and the reverse. This is why no scan can diagnose addiction or tell a particular person how they will fare. The value of imaging lies in revealing mechanisms that apply in general, not in reading individual futures.

Answering Marcus

Nadia explained that the images he found were not pictures of individual people but displays of average differences between groups, colored to make differences visible. She told him research had found changes in dopamine receptors and frontal activity in people who used stimulants heavily, which help explain why craving can be strong and control harder. Then she added what the image left out: studies have found that some of these changes partly recover over months of abstinence, and the brain continues to change with new experience. No scan could tell Marcus his future. His choices in treatment were part of what would shape his brain from here.

Using Imaging in Education

Some programs show clients brain images as part of education. Used carefully, images can help clients understand that craving and difficulty with control have biological roots, which can reduce shame. Used carelessly, they can suggest that the brain is broken. Nadia decided that if she used images in group, she would always pair them with evidence of recovery over time and with a discussion of what clients can do to support that recovery.

Images in Public Messages

Brain images have been used to reduce stigma, by showing addiction as a medical condition, and also in ways that can increase it, by suggesting people with addiction are permanently damaged. Counselors can help clients and families read such images critically, neither dismissing the science nor accepting a message of hopelessness.

A Note on Timing

Scans capture one moment, and the moment matters. A person scanned during the first days after stopping a stimulant will look different from the same person scanned months later, and the studies described here scanned people at different points. Goldstein and Volkow (2002) stressed that frontal changes vary with how recently someone has used and how long they have abstained. For Marcus, this meant that any picture of his brain taken now would describe early recovery rather than a final state, which was the most reassuring point Nadia could offer him honestly.

Conclusion

Neuroimaging has shown reduced dopamine receptors and frontal activity in people who used cocaine, as Volkow and colleagues found, limbic activation during craving, as Childress and colleagues showed, and frontal involvement in compulsive use, as Goldstein and Volkow reviewed. Interpreted carefully, these findings explain why addiction is hard to overcome without implying that individuals are permanently damaged, an interpretation Nadia offered Marcus.

References

Childress, A. R., Mozley, P. D., McElgin, W., Fitzgerald, J., Reivich, M., & O'Brien, C. P. (1999). Limbic activation during cue-induced cocaine craving. American Journal of Psychiatry, 156(1), 11-18. https://doi.org/10.1176/ajp.156.1.11

Goldstein, R. Z., & Volkow, N. D. (2002). Drug addiction and its underlying neurobiological basis: Neuroimaging evidence for the involvement of the frontal cortex. American Journal of Psychiatry, 159(10), 1642-1652. https://doi.org/10.1176/appi.ajp.159.10.1642

Volkow, N. D., Fowler, J. S., Wang, G.-J., Hitzemann, R., Logan, J., Schlyer, D. J., Dewey, S. L., & Wolf, A. P. (1993). Decreased dopamine D2 receptor availability is associated with reduced frontal metabolism in cocaine abusers. Synapse, 14(2), 169-177. https://doi.org/10.1002/syn.890140210