They Were Cigarette Smokers. Then a Stroke Vanquished Their Addiction.

Scanning the injured brain often maps irreparable loss, revealing where the injury causes memory loss and tremors.

However, in rare cases, these scans may reveal the exact opposite. That is, a plot of the brain region where the injury miraculously relieves someone’s symptoms and provides clues as to how doctors can achieve the same.

A team of researchers has re-examined a set of such brain images drawn from nicotine-addicted smokers whose strokes and other injuries voluntarily helped quit smoking. According to scientists, the results show a network of interconnected brain regions that they believe support addiction-related disorders that potentially affect tens of millions of Americans.

the studyPublished in the scientific journal Nature Medicine on Monday, in support of an idea that has recently received a lot of attention. Poisoning is not in one brain region, but in the circuits of regions linked by filamentous nerve fibers.

The results may provide a clearer set of goals for addiction treatment that sends electrical pulses to the brain. This is a new technology that has been shown to be promising in helping people quit smoking.

“One of the biggest problems with addiction is not knowing where in the brain the main problem to be treated is,” said one of the lead authors of the study, a university neurologist. Dr. Juho Joutsa said. Of Turku, Finland. “I hope this will give you very good ideas about these regions and networks.”

Studies over the last two decades have solidified the idea that addiction is a brain disorder. However, many still believe that addiction is voluntary.

Some independent experts have stated that the latest research is a very strong demonstration of the role of the brain in substance use disorders. Among the smokers who suffered a stroke or other brain damage, those who damaged certain neural networks were immediately relieved of their thirst.

Researchers have replicated their findings in another group of patients with brain damage who have completed a risk assessment of alcoholism. Brain networks associated with a low risk of alcoholism are similar to those that alleviate nicotine addiction, suggesting that circuits may underlie broader addiction.

“I think this will be one of the most influential publications in the decade, not just this year,” said A. Thomas McClellan, Professor Emeritus of Psychiatry at the University of Pennsylvania and former Deputy Director of the National Drug Administration. I am saying. Control policies that were not involved in the study. “It rests so many of the stereotypes that are still pervasive in the field of addiction: addiction is bad parenting, addiction is a weak personality, and addiction is a lack of morality.”

In recent years, a series of studies have identified specific brain regions where lesions or injuries may be associated with release from poisoning. However, the target continued to shift.

Dr. Hamed Ektiari, an addiction treatment expert at the Winners Brain Institute in Tulsa, Oklahoma, said:

In a new study, Dr. Youza applied advanced statistical techniques to an old series of brain scans from smokers in Iowa who suffered nerve damage. Previous analysis of the same scan suggested that patients with damage to the islands, the brain regions involved in conscious impulses, were more likely to quit smoking.

However, tracing back the same scan pixel by pixel, Dr. Youza found that many undamaged patients on the island also lost their urge to smoke. “There was something in the island story, but it wasn’t all,” he said.

In collaboration with Dr. Michael Fox, an associate professor of neurology at Harvard Medical School, Dr. Youza examined a second scan set from a smoker who suffered a stroke in Rochester, NY. He examined a total of 129 cases.

The team had a hard time finding individual brain regions that helped ensure that the injury helped the patient quit smoking. Instead, researchers turned to a standard diagram of brain connectivity that shows how activity in one area correlates with activity in another.

Suddenly, researchers were able to find a network of connected brain regions where the injury caused immediate relief from nicotine cravings, and other networks where the injury did not occur.

“What we recognize in many different areas is that our therapeutic target is not the brain regions we once thought of, but the connected brain circuits,” says Dr. Fox. I did. “If you consider how your brain is connected, you can improve your treatment.”

This study did not consider how the patient’s family life (for example, frequency of exposure to tobacco) affected habits. Patients who were considered to have entered remission of their addiction after the injury reported that they generally quit smoking immediately, had no urge to smoke, and did not resume while being followed.

However, researchers have investigated whether other injuries-related changes (such as intelligence and mood) can help explain the disappearance of nicotine cravings in some patients. They didn’t seem to make a difference in the end.

External experts said some of the brain networks identified in the study were familiar to them from previous studies. Dr. Martijn Figee, a psychiatrist at the Advanced Circuit Therapy Center on Mount Sinai in Manhattan, is studying how electrical impulses transmitted to the brain can treat obsessive-compulsive disorder, depression, and addiction. He said addiction generally appears to be associated with underactivity of the brain’s cognitive control circuits and hyperactivity of reward-related circuits.

Physicians suppress activity in certain areas, mimic the effects of injury, and others by applying electrical stimulation to the surface of the patient’s head or by using more invasive methods such as deep brain stimulation. It can stimulate the activity of the area. This study identified a region called the medial anterior cortex that appears to be a good candidate for excitatory stimuli. The area overlapped with treatment goals recently approved by US regulatory agencies to help smokers quit smoking.

This treatment uses an electromagnetic coil placed on the patient’s scalp to send an electrical pulse to the surface of the brain. Other techniques include implanting electrodes in specific brain regions or permanently deactivating the exact brain region.

“This paper is very interesting in that it clearly shows some accessible targets for treatment,” said Dr. Fiji.

Brain stimulation has become more common in the treatment of depression and obsessive-compulsive disorder, but the use of these treatments for addiction has fallen behind. Researchers said it would take years to hone the technique.

Despite studies showing that electrical or magnetic stimuli can reduce the thirst for addictive substances, it is not clear how long their effects will last. Some of the most promising targets are deep in the brain. To reach them, deep brain stimulation or certain types of coils that have just become available may be needed, Dr. Fiji said.

Scientists said knowing where to direct brain stimuli would not solve the problem of which frequency to use. Also, brain connections vary from person to person and treatment may need to be coordinated.

Researchers say that people with addiction are slower to accept brain stimuli than people with depression or movement disorders, partially reflecting the taboo on thinking of addiction as a brain disorder.

There may also be structural challenges. Judy Luiges, assistant professor of psychiatry at the University of Amsterdam Medical Center, was hired from a pool of thousands of patients at the Dutch Addiction Treatment Center for the study of deep brain stimulation therapy. In three years, only two patients started the trial.

Dr. Luiges and her colleagues Written by a patient with substance use disorder This procedure may have been partially avoided because the motivation for tackling the illness was more variable than in patients with obsessive-compulsive disorder.

And the very instability often associated with substance use disorders can make investing in time-consuming treatments more difficult. Only one-third of the patients appointed to the research team brought family and friends, Dr. Luigjes found.

Some scientists are working to address these concerns.Ann Sinai Mountain Addiction TeamFor example, it lowers treatment barriers by providing minimally invasive brain stimulation to patients at home or in community centers rather than in hospitals.

But while the brain may be the gateway to treating addiction, Dr. Luigjes said it was probably not the most important.Other scientists Discussed in recent years Focusing on addiction brain disease models has been able to divert attention and money from studies addressing the social and environmental factors that contribute to addiction.

“We have put much of our hope, money and energy on one side,” she said, noting that this area focuses on brain stimulation. “I don’t know if it will be paid the way we expected.”