A team of Stanford researchers has shown that ‘hypnotizability,’ or how deeply someone can be hypnotized, can be altered using electrical brain stimulation. The researchers also note that previous studies have shown the susceptibility to hypnosis to be a stable trait that didn’t change over time, like IQ or many dominant personality traits, making this discovery somewhat unexpected.
If perfected, the researchers say this process could open up the possibility of clinically proven hypnosis treatments for people suffering from a wide range of conditions while also hinting at the possibility of changing other aspects of the human mind thought previously unchangeable.
Hypnotizability Varies Significantly
In recent decades, therapists treating a wide range of medical disorders have found significant success using hypnosis. However, researchers have also learned that achieving success with hypnotherapies requires an innate ability to become hypnotized.
“We know hypnosis is an effective treatment for many different symptoms and disorders, in particular pain,” said Afik Faerman, PhD, a postdoctoral scholar in psychiatry and lead author of the study. “But we also know that not everyone benefits equally from hypnosis.”
Previous studies have determined that roughly two-thirds of the human population has at least some level of hypnotizability. More narrowly, 15% of the overall population is considered highly hypnotizable, ranking as a 9 or a 10 on a ten-point scale. As a result, only a fraction of the world’s population can truly benefit from hypnotherapy.
In their newly published study, the Stanford team says they now believe that under the right conditions, that candidate pool might be expandable.
People with Higher Hypnotizablity Show Higher Brain Connectivity in Key Regions
“Hypnosis is a state of highly focused attention, and higher hypnotizability improves the odds of your doing better with techniques using hypnosis,” explained David Spiegel, MD, a professor of psychiatry and behavioral sciences and a senior author of the study. In fact, Dr. Spiegel has spent decades studying and utilizing hypnosis to treat patients with a wide range of disorders, including smoking cessation, stress reduction, and pain management.
According to the press release announcing this new technique, “Spiegel led a team that used brain imaging to uncover the neurobiological basis of the practice.” That research showed that contrary to the widely-held idea that people who were more hypnotizable were less intelligent, it turned out to be the opposite.
Brain scans of people with higher hypnotizability actually showed increased connectivity between two specific brain regions: the left dorsolateral prefrontal cortex, which plays a role in the brain’s information processing and decision-making, and the dorsal anterior cingulate cortex, which is involved in the detection of stimuli. Spiegel says this increased connectivity in more hypnotizable people “made sense” as folks who coordinate activity between these two regions should be able to concentrate more intently.
“It’s because you’re coordinating what you are focusing on with the system that distracts you,” he explained.
Hypnotizability Increased By a Full Point After Brain Stimulation
Based on the brain scan data, Spiegel wondered if stimulating those same brain areas in people with lower connectivity could, at least temporarily, increase their ability to become hypnotized.
To test the hypothesis, Spiegel and his colleague Nolan Williams, MD, an associate professor of psychiatry and behavioral sciences, who has pioneered non-invasive neurostimulation techniques to treat depression, obsessive-compulsive disorder, and suicidal ideation, enlisted 80 volunteers suffering from fibromyalgia. A chronic pain condition, fibromyalgia has proven particularly responsive to hypnotherapy in patients who are hypnotizable.
After eliminating members of the group who were already deemed highly hypnotizable, the remaining volunteers underwent electrical brain stimulation. As a control, half of the group went through the same outward procedure as the others, but their paddles were turned off, so they received no actual electrical stimulation of their brains.
The patients who actually received the brain stimulation were subjected to two 46-second applications that delivered 800 individual pulses of electricity to the left dorsolateral prefrontal cortex. To improve the odds of success, detailed brain scans on each individual participant allowed the researcher to customize the placement of the paddles to each person’s actual brain structure.
“A novel aspect of this trial is that we used the person’s own brain networks, based on brain imaging, to target the right spot,” said Williams.
As they had hoped, the volunteers who received the transcranial stimulation showed higher susceptibility to hypnosis immediately after the treatment when compared to their assessed hypnotizablility measured immediately before the stimulation. On average, the increase was by a full point on the ten-point scale.
“We were pleasantly surprised that we were able to, with 92 seconds of stimulation, change a stable brain trait that people have been trying to change for 100 years,” Williams said. “We finally cracked the code on how to do it.”
Using Brain Stimulation and Hypnosis In Tandem Could Dramatically Increase Treatment Options
Notably, the control group who received no stimulation showed no change in hypnotizability. The researchers also found that the increase only lasted for a short time and had completely disappeared an hour after the treatments.
Still, the researchers theorize that this window of opportunity may be enough to allow a whole new group of people to take advantage of the benefits of hypnotherapy. In fact, they believe that further study may show that brain stimulation may improve many other kinds of psychiatric and therapeutic options already in use.
“As a clinical psychologist, my personal vision is that, in the future, patients come in, they go into a quick, non-invasive brain stimulation session, then they go in to see their psychologist,” said Faerman. “Their benefit from treatment could be much higher.”
Christopher Plain is a Science Fiction and Fantasy novelist and Head Science Writer at The Debrief. Follow and connect with him on X, learn about his books at plainfiction.com, or email him directly at christopher@thedebrief.org.