New Food-Addiction Link Found

Mere sight/smell of food spikes levels of brain “pleasure” chemical
UPTON, NY — Scientists at the U.S. Department of Energy’s Brookhaven National Laboratory have found that the mere display of food — where food-deprived subjects are allowed to smell and taste their favorite foods without actually eating them — causes a significant elevation in brain dopamine, a neurotransmitter associated with feelings of pleasure and reward. This activation of the brain’s dopamine motivation circuits is distinct from the role the brain chemical plays when people actually eat, and may be similar to what addicts experience when craving drugs. LCSW CEUs
“Eating is a highly reinforcing behavior, just like taking illicit drugs,” said psychiatrist Nora Volkow, the study’s lead investigator. “But this is the first time anyone has shown that the dopamine system can be triggered by food when there is no pleasure associated with it since the subjects don’t eat the food. This provides us with new clues about the mechanisms that lead people to eat other than just for the pleasure of eating, and in this respect may help us understand why some people overeat.” The study will appear in the June 1, 2002 issue of Synapse (now available online ).

Brookhaven scientists have done extensive research showing that addictive drugs increase the levels of dopamine in the brain, and that addicts have fewer dopamine receptors than non-addicts. Last year, in an effort to understand the relationship of the dopamine system to obesity, they found that obese individuals also had fewer dopamine receptors than normal control subjects.

In the new study, the scientists investigated the role of dopamine in food intake in healthy, non-obese individuals. The researchers used positron emission tomography (PET), a brain-scanning technique, to measure dopamine levels in 10 food-deprived volunteers. Each volunteer was given an injection containing a radiotracer, a radioactive chemical “tag” designed to bind to dopamine receptors in the brain. The PET camera picks up the radioactive signal to measure the level of tracer. Since the tracer competes with dopamine for binding to the receptor, the amount of bound tracer can be used to infer the concentration of dopamine (more bound tracer = less dopamine).


These brain scans can be used to infer brain dopamine levels in the four experimental conditions (with and without food stimulation, paired with and without an oral dose of Ritalin). Note that the tracer signal in the Ritalin + food scan is significantly lower than the others. This is because the radiotracer competes with natural brain dopamine for binding to the receptor. When there is a lot of tracer bound (the first three conditions), it means there is not as much natural brain dopamine. When there is little tracer bound (as in the Ritalin + food scan), there is more natural brain dopamine occupying the receptor sites. So, it is an inverse relationship (a low tracer signal = a high dopamine level). Hi-res image (300 dpi jpeg).



Study subjects’ brains were scanned four times over a two-day period, with and without food stimulation, paired with and without an oral dose of methylphenidate. Methylphenidate (Ritalin) is known to block the reabsorption of dopamine into nerve cells. The researchers wanted to see if it would amplify any subtle changes in dopamine levels.

For food stimulation, the volunteers were presented with foods they had previously reported as their favorites. The food was warmed to enhance the smell and the subjects were allowed to view and smell it, as well as taste a small portion placed on their tongues with a cotton swab. As a control, during scans when food stimulation was not used, subjects were asked to describe in as much detail as possible their family genealogy. Study participants were also instructed to describe, on a scale of 1 to 10, whether they felt hungry or desired food prior to food stimulation and then at five-minute intervals for a total of 40 minutes.

The researchers found that food stimulation in combination with oral methylphenidate produced a significant increase in extracellular dopamine in the dorsal striatum. There was also a correlation between the increase in dopamine triggered by food stimulation and methylphenidate and the changes in self-reports of ‘hunger’ and ‘desire for food.’ “This suggests the dopamine increases during the food/methylphenidate condition reflect the responses to food stimulation and not the isolated effects of methylphenidate,” Volkow said.

The study demonstrates that methylphenidate, when used at low doses, amplifies weak dopamine signals. It also shows, for the first time, that the dopamine system in the dorsal striatum plays a role in food motivation in the human brain.

This relationship was not observed in the ventral striatum, which includes the nucleus accumbens, the area of the brain thought to be responsible for food reward. “We and others previously thought the nucleus accumbens was the primary brain region associated with regulating food intake by modulating reward and pleasure while eating,” said study coauthor Gene-Jack Wang. “These findings challenge that belief.”

This study was funded by the U.S. Department of Energy, which supports basic research in a variety of scientific fields, and the National Institute on Drug Abuse.

High-Tech Treatments

By Beryl Lieff Benderly

A patient arrives in the emergency room of a small hospital in rural Tennessee in acute need of psychiatric evaluation. The attending physician lacks the specialty training to evaluate whether the patient is at risk for suicide or harm to others—requiring hospitalization—and the nearest psychiatric hospital is located more than an hour away. What should the physician do?

In the past, a mobile crisis team would have been dispatched over mountainous roads for an hour's drive to make an evaluation. Today, a high-speed video teleconference between a member of the crisis team and the patient—in real time—takes place instead.

This accelerated evaluation procedure, as described by Susan Dimmick, Ph.D., a project manager at the Oak Ridge Associated Universities, in Oak Ridge, TN, is just one of the many applications of communications technology now available to deliver mental health and substance abuse care efficiently. More than two dozen presenters shared their expertise at a recent conference, "E-Therapy, Telehealth, Telepsychiatry, and Beyond," hosted by SAMHSA's Center for Substance Abuse Treatment (CSAT) in December.

Sheila M. Harmison, D.S.W., L.C.S.W., Special Assistant to the CSAT Director, moderated the conference, which drew researchers and service providers from across the Nation and from Canada to discuss a wide range of innovative programs that use e-mail, text messaging, Web sites, and voice-over-Internet telephone in addition to video teleconferencing. These technologies overcome barriers—including distance, physical immobility, and other disabilities, and social stigma—that prevent many Americans from receiving needed mental health care. Online CEUs for Counselors
Examples of these services include:

Low-income, inner-city mothers who are in recovery from substance abuse stay in daily contact with their counseling program via e-mail.

Children in remote Alaskan villages receive mental health treatment via video teleconference from providers located in facilities hundreds of miles away.

Middle school, high school, and college students participate in personalized substance abuse interventions over the World Wide Web.

Military veterans with post-traumatic stress disorder who live on sparsely settled Indian reservations in South Dakota and Wyoming receive mental health treatment via video teleconference.

Persons undergoing cognitive behavioral therapy for anxiety disorders use palmtop computers to receive messages of reinforcement and assess their own levels of anxiety while they go about their daily activities.

Alcoholics in recovery attend group therapy sessions via streaming video and voice-over-Internet from the privacy of their homes.

"Technology can assist in our larger goal to assure a life in the community for everyone," said CSAT Director H. Westley Clark, M.D., J.D., M.P.H. The goal is not to substitute traditional treatments for mental and addictive disorders, he emphasized. "The goal is to leverage the impact of people-based services."

The use of new communications technology in treatment for these disorders is in its infancy, Dr. Clark continued. "And there does appear to be a reluctance to adopt new technology."

Qualified mental health and substance abuse professionals must make use of these new technologies. Charlatans and quacks are trying to exploit the Internet and entice the unwary into many questionable so-called therapies, Dr. Clark cautioned. "If we in the orthodox community refuse to go ‘into the ether,' others will have no compunction." In other words, research needs to go forward vigorously to evaluate the usefulness of the various technology-assisted treatment approaches. "We have to determine if e-therapy is a reliable resource for substance abuse and mental health treatment," said Dr. Clark. "I think it is."

Kathryn Power, M.Ed., Director of SAMHSA's Center for Mental Health Services, also addressed the conference. "E-health, properly researched and implemented, holds great promise for improving the mental health of millions of Americans nationwide," she said. Not only is e-health incorporated in the goals of the SAMHSA Mental Health Transformation initiative, but through the use of these technologies excellent mental health care is delivered, and research accelerated.

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High-Tech Options
As equipment and service costs continue to decrease and the availability of high-speed broadband connections continues to increase, mental health and substance abuse practitioners find themselves with many advanced options for audio, video, and text technologies.

Wireless connections now match the speed of broadband cable modems, said Brent Carter, a product development officer for Verizon Wireless, in his presentation.

Advanced encryption and other security measures allow wireless communications to meet the privacy and confidentiality requirements of mental health and substance abuse professionals, added Donald "Desi" Arnaiz, M.A., President of Virginia Systems, Inc., and an engineer for Comcast. "Everything that you require for the Health Insurance Portability and Accountability Act—HIPAA—is available to you now."

Mental health and substance abuse treatment providers and other health care providers, however, must be sure to use equipment correctly. When selecting devices, for example, they must make certain that they obtain proper security technology. "Most people don't protect their wireless systems, but care providers must take that extra precaution," said Mr. Arnaiz.

Other recommendations include choosing devices appropriate to the intended purpose and making sure that all devices work together. Correcting errors in the integration of devices is in fact his company's "biggest headache," Mr. Arnaiz said. For practitioners to have a successful program, they must also spend time learning to use the equipment.

Some adaptations in treatment techniques will also be needed to meet the demands of technology, noted Ron Adler, Chief Operating Officer of the Alaska Psychiatric Hospital. His experience with the hospital's TeleBehavioral Health video teleconferencing system convinced him that the benefits vastly outweigh the costs in both time and money. "Build this system and the funding will come and the patients will come," he urged conference participants.