Posts Tagged ‘Insula’

Suggestible You 3

March 19, 2017

“Suggestible You” is the title of a book by Erik Vance.  The subtitle is “The Curious Science of Your Brain’s Ability to Deceive, Transform, and Heal.  This book is about the placebo response and related phenomena.   This is the third post on this book.

Irving Kirsch took up psychology out of a philosophical curiosity about the brain.  He mentored Ted Kaptchuk, a researcher who earned a Chinese doctorate in Eastern medicine and was an expert in acupuncture and other alternative therapies.  These two set up a lab at Harvard and for a long time their names have been synonymous with placebo research.  Kaptchuk’s work spans many complicated aspects of placebo research—genetic, biochemical—but Vance’s favorite study is a relatively simple one.  He handed patients pills and told them it was a placebo.  He explained that placebos had been shown to be very effective agains all manner of conditions, and so forth.  When these patients took the pill, it still worked.  Not as well as a secret placebo—but it worked, even though the people taking it knew it wasn’t real.

Tor Wager conducted research using functional magnetic resonance imaging f(MRI).  fMRI measures blood flow in the brain.  This blood flow is used to infer brain activity.  It is captured in voxels. A single voxel has about 63,000 neurons in it (and four times as much connective).  Nevertheless, fMRI has been invaluable in gaining insights regarding the brain.  Wager used fMRI to capture the placebo effect in action.  The first experiment used electric shock.  The research participants saw either a red or a blue spiral on a screen warning them hey would get either a strong or a mild shock, which would hit between 3 and 12 seconds later to keep them off guard (and build expectation).  Wager  looked two skin creams explaining that a one was designed to reduce the  pain and the other was a placebo.  Actually both skin creams were placebos, but the research participants said they felt less pain with the “active” cream.

The second experiment used a hot metal pad that seared the skin for 20 seconds.  This time the screen just read, “Get Ready,” and then the pad heated up.  As in the first experiment, the research participants received placebo and “pain killing” creams, both of which were actually placebos.  Wager surreptitiously lowered the temperature of the heat pad on the fake “active” cream, fooling the research participants into thinking that the cream was reducing the level of pain they felt.  Then, in the last phase (as Collca had with Vance’s shocks), he kept the temperature high.  Researchers carefully recorded how much pain the subjects reported feeling, and Wager also had their fMRI brain scans.  What the research participants reported about their pain tracked perfectly with the activation of several parts of the brain associated with pain, such as the anterior cingulate cortex (which plays a role in emotions, reward systems, and empathy), the thalamus (which handles sensory perception and alertness), and the insula (which is related to consciousness and perception).  Those reporting less pain from the placebo effect showed less activity in the key pain-related brain regions.  And those who felt less of the placebo effect showed more activity.  So these research participants were not imaging less pain; they were feeling it.

More importantly, Wager observed the route that the placebo response takes from anticipation to the release of drugs inside the brain.  Pain signals normally begin in the more primitive base of the brain (relaying information from wherever in the body the pain starts) and radiate outwards.  What Ager observed was backward, with the pain signals starting in the prefrontal cortex—the most advanced logic part of the brain with executive functions—and working back to the more primitive regions.  Vance noted that this seemed to suggest a sort of collision of information:  half originating in the body as pain, and half originating in the advanced part of the brain as expectation.  Whatever comes out of that collision is what we feel.

The following summary comes directly from Vance’s book,”Pain, like any sensation, starts in the body, goes up the spine, and then travels to the deeper brain structures that distribute that information to places like the prefrontal cortex, where we can contemplate it.  Placebos, on the other hand, seem to start in the prefrontal cortex (just behind the right temple) and go backward.  They work their way to parts of the brain that handle opioids and release chemicals that dull the pain.  That also seem to tamp down activity in the parts of the brain that recognize pain in the first place.  And you feel better.  All in a fraction of a second.”

How powerful these placebo effects are varies.  In some people they barely register.  However, in others the opioid dumps can be so powerful that people become physically addicted to their own internal opioids, similar, in theory, to how people become addicted to laudanum. One theory even suggests that chronic pain might be the result of a brain addicted to its inner pharmacy, in essence, looking for a fix.

More than opioids are involved.  Over the past few decades, other brain chemical have been shown to trigger the placebo effect.    Our inner pharmacy also stocks endocannabinoids—the same chemicals found in marijuana that play an important role in pain suppression—and serotonin,  which is important intestinal movements and is the primary neurotransmitter involved in feelings of happiness and well-being.

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How Placebos Could Change Research and Practice

March 29, 2015

The title was on the cover of the April 2015 Monitor on Psychology of the American Psychological Association.  Inside the issue was an article by Stacy Lu, “Great expectations:  New research is leading to an understanding of how placebos work—findings that may lead to more effective treatments and better drug research.  Our understanding and attitudes towards placebos is advancing.

In one study neuroscience researcher Shaffer and his colleagues asked participants to apply a “powerful analgesic” on their hands and arms.  Then the researchers administered small bursts of heat where the cream had been applied.  The cream was actually petroleum jelly, but participants reported that the s-called powerful cream protected them from feeling as much of a burn  as a control cream.  Even after the researchers showed them that the active cream was just petroleum jelly, it made little difference.  The participants still reported less pain from the heat when they were re-tested versus the control cream (The Journal of Pain, 2015).

Today scientists are studying  placebos as a psychobiological  phenomenon and the placebo response as a potentially important part of the success of many medical treatments.  Psychological assessments, brain scans, and genotyping are used  to understand better how placebo responses work and to identify who may be most likely to respond to them.  Placebos are similar to cognitive therapies in that they tap into people’s beliefs that there’s hope and that they will get better.

A meta-analysis of 25 neuroimaging studies of pain and placebos conducted by Wager and Atlas of the National Center for Complementary and Integrative Health (NCCIH) found that people who took placebos and expected have reduced pain had less activity in brain regions associated with pain processing, including the dorsal anterior cingulate, thamalus, and insula (Handbook of Experimental Pharmacology, 2014).

Research suggests that placebos have the greater effect in neural systems involved with processing reward seeking, motivation, and emotion.  Placebos seem to work especially well in patients with depression, Parkinson’s disease, and pain.  All three conditions involve the neurotransmitter dopamine.  These are also areas where people can consciously monitor their own treatment results.

In a study of patients with Parkinson’s disease Wager and colleagues found that simply expecting medication altered brain activity in the striatum and ventromedial prefrontal cortex in brain areas associated with reward learning in ways similar to actual dopaminergic medication (Nature Neuroscience, 2014).

In another study of people with migraines, placebos elicited a response without any verbal cue to effectiveness,   Slavenka Kam-Hansen and colleagues openly labeled placebo pills for some patients who reported as much pain relief as those who also got a placebo but had been told that they’d received real medication. (Science Translational Medicine, 2014).

Genetics research has found that participants with a specific genotype related to having more dopamine in the prefrontal cortex reported having a larger effect from a placebo  treatment  than participants with a genotype that produces less dopamine in the prefrontal cortex (PLOS ONE, 2012).

Children seem to respond especially well to placebos.  In one study their placebo response was 5.6 that of adults (The Journal of Pain, 2014).

Patients are interested and enthusiastic about placebo  treatments.  They are pleased to discover that they can contribute to their own healing.

Why Are Older People More Vulnerable to Fraud?

December 19, 2012

It is always depressing hearing a story about an elderly couple who have lost their entire life savings to a scam. But one also wonders how people with so many years of experience can fall for such a scam. One would think that as we age we would become less, not more, vulnerable. An article in a Special Section on Aging in the Washington Post1 provides some insight.

According to the Federal Trade Commission (FTC), up to 80% of scam victims are older than 65. The tendency of the elderly to accentuate the positive makes them easy marks according to the FTC and the FBI. According to social neuroscientist Shelly Taylor, “Older people are good at regulating their emotions, seeing things in a positive light, and not overreacting to everyday problems.”2 Taylor and her colleagues showed pictures of faces considered trustworthy, neutral, or untrustworthy to a group up of 119 older adults (aged 55 to 84) and 24 younger adults (aged 20 to 42). “Signs of untrustworthiness included averted eyes; an insincere smile that doesn’t reach the eyes; a smug, smirky mouth, and a backward tilt of the head.”3 Each face was rated on a scale from minus 3 (very untrustworthy) to 3 (very trustworthy). The results indicated that the untrustworthy faces were rated as significantly more trustworthy by the older subjects than by the younger ones.

The same researchers then performed the same test with new participants. However, this time the brains of the participants were imaged looking for differences in brain activity between the age groups. When the younger subjects were asked to judge whether the faces were trustworthy, the anterior insula became active. This activity increased during the sight of an untrustworthy face. However, older people showed little or no activation. According to Taylor the insula’s job is to collect information not about others, but about one’s own body, sensing feelings and the so-called gut instincts, and presenting that information to the rest of the brain. “It’s a warning bell that doesn’t seem to work as well in older people.” It appears that the optimistic tendency of the elderly might be overriding this warning signal.

It is curious to speculate as to why the elderly tend towards optimism. As we age, we close in on the prospect of our own death, and have likely experienced the passing of loved ones. Physical and cognitive problems are likely to present themselves. Social relationships can deteriorate and be lost, so loneliness can be a problem. An optimistic attitude can be quite helpful in coping with these difficulties. Nevertheless, the elderly need to realize that this optimistic attitude can make them vulnerable to fraud. See also the healthymemory blog posts, “Will Baby Boomers Be More Vulnerable to Scams?” and “The Distinctiveness Heuristic.” Enter “Optimism” in the search box to find more posts regarding optimism and its positive and negative merits.

1Norton, E. (2012). Why Older People Get Scammed, Washington Post, December 11, E4.

2Ibid.

3Ibid.

© Douglas Griffith and healthymemory.wordpress.com, 2012. Unauthorized use and/or duplication of this material without express and written permission from this blog’s author and/or owner is strictly prohibited. Excerpts and links may be used, provided that full and clear credit is given to Douglas Griffith and healthymemory.wordpress.com with appropriate and specific direction to the original content.