Could brain stimulation be the answer to ending drug addiction?
TMS might also help those with anxiety, PTSD, and traumatic brain injury.
According to government statistics, 21.5 million Americans suffer from a substance abuse disorder, alcoholism being the most common. As of 2014, 64,000 lost their lives to some type of overdose. Although many treatment options are available, no matter the type of addiction, recidivism rates are exceptionally high. Now, researchers at the Medical University of South Carolina believe they can reboot the brain’s reward center and halt addiction. This is done through something called repeated trans-cranial magnetic stimulation (rTMS). What is TMS and how has it been shown to help those gripped by addiction?
TMS is a non-invasive procedure where a coil is placed on the scalp, which passes magnetic impulses through the skull. It’s believed that a changing magnetic field applied to certain parts of the brain increases coherence between cortical areas—essentially improving communication between different brain regions. The FDA approved this technique a decade ago to help ease the symptoms of depression when antidepressants failed to work.
The frequency applied during TMS can be as high as 10-20 Hertz or as low as 1 Hertz, depending on a person’s motor threshold. Motor threshold is determined by how much frequency is required to make a patient’s leg muscle or thumb jump, when TMS is applied to the brain’s motor strip. It doesn’t hurt. Patients report feeling a tapping sensation on the head. Sessions last 30 minutes and typically, treatment takes place a few times a week for six weeks.
A patient undergoes trans-cranial magnetic stimulation (TMS). Image credit: Getty Images.
Since it’s applied to the scalp, deeper areas of the brain cannot be reached. However, TMS has shown to help those with depression by stimulating a part of the brain called the prefrontal cortex. Physicians are considering TMS for other conditions too, such as Parkinson’s, epilepsy, chronic pain, and schizophrenia. While brain stimulation has been used for decades to treat psychiatric disorders, only recently have researchers been experimenting with TMS to treat addiction.
The idea was inspired by a 2013 National Institute on Drug Abuse (NIDA) study, led by neuroscientists Antonello Bonci and Billy Chen. They used rats who were so addicted to cocaine, they’d risk a series of painful electric shocks in order to get their fix. The rodents had also been genetically altered, making the neurons in their brains responsive to light. When the scientists stimulated the area of the brain known for impulse control, the rats were able to kick the habit immediately. Bonci in the paper wondered if TMS might have a similar effect.
Luca Rossi—an Italian physician addicted to crack cocaine and his father, a chemist, after learning of this study, decided to approach Italian addiction specialist Luigi Gallimberti with the idea. Since then, Gallimberti’s lab has treated over 300 addicts with TMS. For addiction, generally the ventromedial prefrontal cortex, the reward center of the brain, is stimulated. This is thought to be where addiction originates from. Unfortunately, we still don’t know all the ins and outs of how addiction effects the brain. As a result, there’s no current treatment based on altering the neural circuit responsible for addiction, yet.
The ventromedial prefrontal cortex is the location of the brain’s reward center and as such, is responsible for addiction. Image credit: National Institutes of Mental Health (NIMH).
One thing we do know is that addiction hijacks the brain’s reward circuit. It floods the brain with dopamine—which gives us that warm, euphoric feeling. As a result, the brain’s dopamine receptors get accustomed to being flush with the feel good neurotransmitter. After awhile they get used to having a certain amount, a tolerance is built up, and so the person needs more and more just to get the same result, leading to addiction. Now, researchers at Medical University of South Carolina are the first to illustrate that TMS can reduce brain activity associated with addiction in cases of chronic cocaine and alcohol abuse. These findings were published in the journal Biological Psychiatry: Cognitive Neuroscience and Neuroimaging.
Researchers carried on two concurrent studies. Study author Tonisha Kearney-Ramos, Ph.D. led these, which were supervised by senior author Colleen Hanlon, PhD. The first part included 24 alcoholics and the second, 25 cocaine addicts. Each underwent an actual TMS session and a faked one, where researchers pretended to administer TMS, but didn’t actually turn on the machine. Scientists then took brain scans using an fMRI before and after TMS took place, to rate each participant’s response to drug or alcohol cues, such as being shown a liquor bottle.
Often, brain activity in the ventromedial prefrontal cortex becomes elevated when the person witnesses something related to their addiction. This is called cue reactivity. When they underwent bona fide TMS, participants showed less cue reactivity than after the sham session. What remains to be seen however, is if these changes result in reduced drug or alcohol use. According to the researchers, repeated TMS sessions might work. Cue reactivity is a big part of a lot of other conditions too, such as anxiety, PTSD, and traumatic brain injury. TMS may be able to help these patients as well.
To learn more about TMS, click here:
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Whether or not women think beards are sexy has to do with "moral disgust"
- A new study found that women perceive men with facial hair to be more attractive as well as physically and socially dominant.
- Women tend to associate more masculine faces with physical strength, social assertiveness, and formidability.
- Women who display higher levels of "moral disgust," or feelings of repugnance toward taboo behaviors, are more likely to prefer hairy faces.
Beards and perceptions of masculinity<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yMjU5OTg0MC9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTY0NzkxMjM3N30.cH-GqNwP5GVqvstgJWAhBPn1B_lYpVEAI0I7iax7EQw/img.jpg?width=1245&coordinates=0%2C1900%2C0%2C849&height=700" id="caae6" class="rm-shortcode" data-rm-shortcode-id="cb0a355a4e8e1899789bc45f3f7aef56" data-rm-shortcode-name="rebelmouse-image" />
Photo Credit: Wikimedia<p>The study used 919 American (mostly white) women ages 18-70 who rated 30 pictures of men they were shown with various stages of facial hair growth. The photographs depicted men with faces that had been digitally altered to look more feminine or more masculine, with a beard and without a beard. The women rated the men according to perceived attractiveness for long-term and short-term relationships. The study found that the more facial hair the men had, the higher the men were rated on their attractiveness, particularly for their suitability for a long-term relationship.</p><p>Part of this might be attributed to facial masculinity — i.e. protruding brow ridge, wide cheekbones, thick jawline, and deeply set narrow eyes — which conveys information to a woman about a man's underlying health and formidability. Women tend to associate more masculine faces with physical strength and social assertiveness. It can also indicate a man with a superior immune response. The researchers suggested that their findings favoring bearded men could be due to the fact that facial hair enhances the masculine facial features on a man's face, like creating the illusion of a thicker jaw line. This could communicate direct benefits to women like resources and protection that would enhance survival among mothers and their infants. In other words, while a beard doesn't mean superior genetics in and of itself, it might be a primitive, ornamental way of saying, "Hey girl, I'm a testosterone-fueled lean, mean, pathogen fighting machine." <br></p><p>It could also be that a beard becomes its own destiny. The researchers in this study cite prior research that found that by growing a beard, men felt more masculine and had higher levels of serum testosterone, which was linked to a higher level of social dominance. They also tended to subscribe to more old-school beliefs about gender roles in their relationships with women as compared to men with clean-shaven faces.<span></span><br></p>
What does disgust have to do with beard preference?<p>Obviously, not all women dig beards. The researchers were particularly interested in what traits make a women prefer bearded men over clean-shaven faces. They looked into several factors including a woman's disgust levels on various concepts, her desire to become pregnant, and her exposure to facial hair in her personal life. </p><p>According to the study, women who were not into facial hair were turned-off by potential parasites or other critters they imagined could be in the hair or skin. Women ranking high on this "ectoparasite disgust" scale might have viewed beards as a sign of poor grooming habits. However, women who ranked higher in levels of "pathogen" did find the bearded men to be desirable, possibly because they perceived beards as a signal of good health and immune function. An intriguing discovery in the study was links to morality. Women who displayed higher levels of "moral disgust," or feelings of repugnance toward taboo behaviors, were more likely to prefer hairy faces. The authors opined that this could reflect a link between beardedness, politically conservative outlooks, and traditional views regarding performances of masculinity in heterosexual relationships.</p>
Additional findings<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yMjU5OTg1My9vcmlnaW4uZ2lmIiwiZXhwaXJlc19hdCI6MTYyNDI1NjUyOX0.P9B8WbmJR0q4nfzYZKbuNSA-2SAigVWJgrQE-_Gxlds/img.gif?width=980" id="49143" class="rm-shortcode" data-rm-shortcode-id="2ed3b1d6f20fc170bf2974646e565e8d" data-rm-shortcode-name="rebelmouse-image" />Giphy<p>The correlations that existed between married and single women's rating on the attractiveness of beards were not particularly clear, although the researchers noted that single and married women who wanted children tended to find beards more attractive than the women who didn't want children. They also found that women with bearded husbands found beards to be more attractive, which might indicate that social exposure to beards influences how desirable they are perceived of as being. Or it could be that men with wives who like beards grow beards.</p><p>It's important to note that culture plays a huge role in how attractive women perceive certain male characteristics as being. This study looked at a small, culturally specific group of American women, so no big, universal claims should be made about masculinity, facial hair, and male desirability to women. However, research like this is important in highlighting how human grooming decisions are driven by much more than fashion trends. Sociobiological, economic, and ecological factors all play a part in the way we choose to present ourselves.</p>
Dominique Crenn, the only female chef in America with three Michelin stars, joins Big Think Live.
Having been exposed to mavericks in the French culinary world at a young age, three-star Michelin chef Dominique Crenn made it her mission to cook in a way that is not only delicious and elegant, but also expressive, memorable, and true to her experience.
New experiments find weird quantum activity in supercold gas.
Quantum Mechanics, Onions, and a Theory of Everything<span style="display:block;position:relative;padding-top:56.25%;" class="rm-shortcode" data-rm-shortcode-id="036ae7b8dd661df2d125a3421a0299ba"><iframe type="lazy-iframe" data-runner-src="https://www.youtube.com/embed/bcVruA0AJ-o?rel=0" width="100%" height="auto" frameborder="0" scrolling="no" style="position:absolute;top:0;left:0;width:100%;height:100%;"></iframe></span>
Researchers say that moral self-licensing occurs "because good deeds make people feel secure in their moral self-regard."
Books about race and anti-racism have dominated bestseller lists in the past few months, bringing to prominence authors including Ibram Kendi, Ijeoma Oluo, Reni Eddo-Lodge, and Robin DiAngelo.