Hendler and her colleagues wondered whether targeting the specific brain regions tied to specific conditions could be a more effective way of helping people with specific symptoms.
In a series of four different experiments with several dozen healthy people, Hendler and her colleagues asked the volunteers to sit inside a functional magnetic resonance imaging (fMRI) machine while simultaneously wearing an electroencephalogram (EEG) hat. The fMRI provided detailed information about which brain regions were active, and the EEG measured activity in the amygdala; together, they allowed the team to pinpoint the precise EEG signature that corresponded to amygdala activation.
Participants were then treated with neurofeedback, in one of two ways: In one condition, they listed to a sound, and in the other, they were shown a movie of a person riding a skateboard. But what they didn't know was that the loudness of the sound they were hearing, or the speed of the person on the skateboard, was actually determined by the electrical activity going on in their own amygdala. The researchers channeled the measurements coming from the fMRI and EEG into an audible sound or a moving image.
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The participants were asked to use "mental strategies" to make either the sound grow quieter, or the skateboarder go faster. If they succeeded, what they were really doing was tamping down the activity in their amygdala. [10 Things You Didn't Know About the Brain]
In a control group, participants were asked to do the same thing, but were treated with a fake neurofeedback. Unlike the true treatment group, the speed of the skateboard and the level of the sound were unrelated to the amygdala's activity, meaning that when the participants observed a change in the skateboarder's speed or the sound's volume, they were not altering their brain activity levels directly.
Next, people in both groups were asked to look at the faces of happy and sad people with either similar or discordant words above them. Past studies have shown that people who are better able to regulate their emotions are quicker to identify a person's facial expression when the word above that person's picture conflicts with the picture, than can people who have had traumatic stress, the researchers wrote in the article.
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The results showed that, compared to those who received the sham treatment, people who were given cues based on activity in the amygdala were better able to reduce activity in that region of the brain "It's actually quite amazing that this plasticity takes place after one session or two sessions," Hendler said. Other psychotherapy techniques aimed at treating PTSD or anxiety often take six, eight or 10 sessions, she said. However, she noted that the participants were all healthy. People with traumatic stress could require more sessions to master the method of controlling their mental activity, Hendler said.
What's more, in follow-up experiments, the participants showed a better ability to regulate emotions as measured by the facial-expression-recognition task.
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The findings suggest that this type of neurofeedback technique could one day become a cheap and relatively simple way for patients to be treated for anxiety, PTSD or other psychological conditions that are tied to amygdala hyperactivation, Hendler said.
Right now, the treatment requires an EEG cap that calls for gel and wiring, making it unsuitable for home use. But in the future, the team envisions using a wireless, miniature sensor that a patient could use at home, after an initial instructional session with a physician, Hendler said.
However, follow-up studies need to show that this method of targeted brain training works as well as techniques like mindfulness meditation or cognitive behavioral therapy, Hendler said.
"We hope this is a better way to actually modulate specific areas, and bring on some plasticity that is necessary to cure the brain," Hendler said.
Original article on Live Science.
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