Posts Tagged ‘Sarah C. P. Williams’


By scanning the brains of subjects while they were hypnotized, researchers at the School of Medicine were able to see the neural changes associated with hypnosis.

By Sarah C.P. Williams

Your eyelids are getting heavy, your arms are going limp and you feel like you’re floating through space. The power of hypnosis to alter your mind and body like this is all thanks to changes in a few specific areas of the brain, researchers at the Stanford University School of Medicine have discovered.

The scientists scanned the brains of 57 people during guided hypnosis sessions similar to those that might be used clinically to treat anxiety, pain or trauma. Distinct sections of the brain have altered activity and connectivity while someone is hypnotized, they report in a study published online July 28 in Cerebral Cortex.

“Now that we know which brain regions are involved, we may be able to use this knowledge to alter someone’s capacity to be hypnotized or the effectiveness of hypnosis for problems like pain control,” said the study’s senior author, David Spiegel, MD, professor and associate chair of psychiatry and behavioral sciences.

A serious science

For some people, hypnosis is associated with loss of control or stage tricks. But doctors like Spiegel know it to be a serious science, revealing the brain’s ability to heal medical and psychiatric conditions.

“Hypnosis is the oldest Western form of psychotherapy, but it’s been tarred with the brush of dangling watches and purple capes,” said Spiegel, who holds the Jack, Samuel and Lulu Willson Professorship in Medicine. “In fact, it’s a very powerful means of changing the way we use our minds to control perception and our bodies.”

Despite a growing appreciation of the clinical potential of hypnosis, though, little is known about how it works at a physiological level. While researchers have previously scanned the brains of people undergoing hypnosis, those studies have been designed to pinpoint the effects of hypnosis on pain, vision and other forms of perception, and not the state of hypnosis itself.

“There had not been any studies in which the goal was to simply ask what’s going on in the brain when you’re hypnotized,” said Spiegel.

Finding the most susceptible

To study hypnosis itself, researchers first had to find people who could or couldn’t be hypnotized. Only about 10 percent of the population is generally categorized as “highly hypnotizable,” while others are less able to enter the trancelike state of hypnosis. Spiegel and his colleagues screened 545 healthy participants and found 36 people who consistently scored high on tests of hypnotizability, as well as 21 control subjects who scored on the extreme low end of the scales.

Then, they observed the brains of those 57 participants using functional magnetic resonance imaging, which measures brain activity by detecting changes in blood flow. Each person was scanned under four different conditions — while resting, while recalling a memory and during two different hypnosis sessions.

“It was important to have the people who aren’t able to be hypnotized as controls,” said Spiegel. “Otherwise, you might see things happening in the brains of those being hypnotized but you wouldn’t be sure whether it was associated with hypnosis or not.”

Brain activity and connectivity

Spiegel and his colleagues discovered three hallmarks of the brain under hypnosis. Each change was seen only in the highly hypnotizable group and only while they were undergoing hypnosis.

First, they saw a decrease in activity in an area called the dorsal anterior cingulate, part of the brain’s salience network. “In hypnosis, you’re so absorbed that you’re not worrying about anything else,” Spiegel explained.

Secondly, they saw an increase in connections between two other areas of the brain — the dorsolateral prefrontal cortex and the insula. He described this as a brain-body connection that helps the brain process and control what’s going on in the body.

Finally, Spiegel’s team also observed reduced connections between the dorsolateral prefrontal cortex and the default mode network, which includes the medial prefrontal and the posterior cingulate cortex. This decrease in functional connectivity likely represents a disconnect between someone’s actions and their awareness of their actions, Spiegel said. “When you’re really engaged in something, you don’t really think about doing it — you just do it,” he said. During hypnosis, this kind of disassociation between action and reflection allows the person to engage in activities either suggested by a clinician or self-suggested without devoting mental resources to being self-conscious about the activity.

Treating pain and anxiety without pills

In patients who can be easily hypnotized, hypnosis sessions have been shown to be effective in lessening chronic pain, the pain of childbirth and other medical procedures; treating smoking addiction and post-traumatic stress disorder; and easing anxiety or phobias. The new findings about how hypnosis affects the brain might pave the way toward developing treatments for the rest of the population — those who aren’t naturally as susceptible to hypnosis.

“We’re certainly interested in the idea that you can change people’s ability to be hypnotized by stimulating specific areas of the brain,” said Spiegel.

A treatment that combines brain stimulation with hypnosis could improve the known analgesic effects of hypnosis and potentially replace addictive and side-effect-laden painkillers and anti-anxiety drugs, he said. More research, however, is needed before such a therapy could be implemented.

The study’s lead author is Heidi Jiang, a former research assistant at Stanford who is currently a graduate student in neuroscience at Northwestern University.

Other Stanford co-authors are clinical assistant professor of psychiatry and behavioral sciences Matthew White, MD; and associate professor of neurology Michael Greicius, MD, MPH.

The study was funded by the National Center for Complementary and Integrative Health (grant RCIAT0005733), the National Institute of Biomedical Imaging and Bioengineering (grant P41EB015891), the Randolph H. Chase, M.D. Fund II, the Jay and Rose Phillips Family Foundation and the Nissan Research Center.

Stanford’s Department of Psychiatry and Behavioral Sciences and Department of Neurology and Neurological Sciences also supported the work.

Jiang H, White MP, Greicius MD, Waelde LC and Spiegel D. Brain Activity and Functional Connectivity Associated with Hypnosis. Cerebral Cortex. 2016 July 28;[Epub ahead of print].

http://med.stanford.edu/news/all-news/2016/07/study-identifies-brain-areas-altered-during-hypnotic-trances.html

By Sarah C. P. Williams

There’s a reason people say “Calm down or you’re going to have a heart attack.” Chronic stress—such as that brought on by job, money, or relationship troubles—is suspected to increase the risk of a heart attack. Now, researchers studying harried medical residents and harassed rodents have offered an explanation for how, at a physiological level, long-term stress can endanger the cardiovascular system. It revolves around immune cells that circulate in the blood, they propose.

The new finding is “surprising,” says physician and atherosclerosis researcher Alan Tall of Columbia University, who was not involved in the new study. “The idea has been out there that chronic psychosocial stress is associated with increased cardiovascular disease in humans, but what’s been lacking is a mechanism,” he notes.

Epidemiological studies have shown that people who face many stressors—from those who survive natural disasters to those who work long hours—are more likely to develop atherosclerosis, the accumulation of fatty plaques inside blood vessels. In addition to fats and cholesterols, the plaques contain monocytes and neutrophils, immune cells that cause inflammation in the walls of blood vessels. And when the plaques break loose from the walls where they’re lodged, they can cause more extreme blockages elsewhere—leading to a stroke or heart attack.

Studying the effect of stressful intensive care unit (ICU) shifts on medical residents, biologist Matthias Nahrendorf of Harvard Medical School in Boston recently found that blood samples taken when the doctors were most stressed out had the highest levels of neutrophils and monocytes. To probe whether these white blood cells, or leukocytes, are the missing link between stress and atherosclerosis, he and his colleagues turned to experiments on mice.

Nahrendorf’s team exposed mice for up to 6 weeks to stressful situations, including tilting their cages, rapidly alternating light with darkness, or regularly switching the mice between isolation and crowded quarters. Compared with control mice, the stressed mice—like stressed doctors—had increased levels of neutrophils and monocytes in their blood.

The researchers then homed in on an explanation for the higher levels of immune cells. They already knew that chronic stress increases blood concentrations of the hormone noradrenaline; noradrenaline, Nahrendorf discovered, binds to a cell surface receptor protein called β3 on stem cells in the bone marrow. In turn, the chemical environment of the bone marrow changes and there’s an increase in the activity of the white blood cells produced by the stem cells.

“It makes sense that stress wakes up these immune cells because an enlarged production of leukocytes prepares you for danger, such as in a fight, where you might be injured,” Nahrendorf says. “But chronic stress is a different story—there’s no wound to heal and no infection.”

In mice living with chronic stress, Nahrendorf’s team reported today in Nature Medicine, atherosclerotic plaques more closely resemble plaques known to be most at risk of rupturing and causing a heart attack or stroke. When the scientists blocked the β3 receptor, though, stressed mice not only had fewer of these dangerous plaques, but also had reduced levels of the active immune cells in their plaques, pinpointing β3 as a key link between stress and atheroscelerosis.

The finding could lead to new drugs to help prevent cardiovascular disease, suggests biologist Lynn Hedrick of the La Jolla Institute for Allergy and Immunology in San Diego, California. “I think this gives us a really direct hint that the β3 receptor is important in regulating the stress-induced response by the bone marrow,” Hedrick says. “If we can develop a drug that targets the receptor, this may be very clinically relevant.”

More immediately, the new observations suggest a way that clinicians could screen patients for their risk of atherosclerosis, heart attack, and stroke, Tall says. “Rather than asking four questions about stress levels, we could use their white blood cell counts to monitor psychosocial stress,” he says.

Thanks to Dr. Rajadhyaksha for bringing this to the attention of the It’s Interesting community.

http://news.sciencemag.org/biology/2014/06/how-stress-can-clog-your-arteries