Research Into Pain Shows That When People Expect More Pain, They Feel More Pain

A good study that’s needed to be done for a while.

Expect a shot to hurt and it probably will, even if the needle poke isn’t really so painful. Brace for a second shot and you’ll likely flinch again, even though — second time around — you should know better.

That’s the takeaway of a new brain imaging study published in the journal Nature Human Behaviour which found that expectations about pain intensity can become self-fulfilling prophecies. Surprisingly, those false expectations can persist even when reality repeatedly demonstrates otherwise, the study found.

“We discovered that there is a positive feedback loop between expectation and pain,” said senior author Tor Wager, a professor of psychology and neuroscience at the University of Colorado Boulder. “The more pain you expect, the stronger your brain responds to the pain. The stronger your brain responds to the pain, the more you expect.”

For decades, researchers have been intrigued with the idea of self-fulfilling prophecy, with studies showing expectations can influence everything from how one performs on a test to how one responds to a medication. The new study is the first to directly model the dynamics of the feedback loop between expectations and pain and the neural mechanisms underlying it.

Marieke Jepma, then a postdoctoral researcher in Wager’s lab, launched the research after noticing that even when test subjects were shown time and again that something wouldn’t hurt badly, some still expected it to.

“We wanted to get a better understanding of why pain expectations are so resistant to change,” said Jepma, lead author and now a researcher at the University of Amsterdam.

The researchers recruited 34 subjects and taught them to associate one symbol with low heat and another with high, painful heat.

Then, the subjects were placed in a functional magnetic resonance imaging (fMRI) machine, which measures blood flow in the brain as a proxy for neural activity. For 60 minutes, subjects were shown low or high pain cues (the symbols, the words Low or High, or the letters L and W), then asked to rate how much pain they expected.

Then varying degrees of painful but non-damaging heat were applied to their forearm or leg, with the hottest reaching “about what it feels like to hold a hot cup of coffee” Wager explains.

Then they were asked to rate their pain.

Unbeknownst to the subjects, heat intensity was not actually related to the preceding cue.

The study found that when subjects expected more heat, brain regions involved in threat and fear were more activated as they waited. Regions involved in the generation of pain were more active when they received the stimulus. Participants reported more pain with high-pain cues, regardless of how much heat they actually got.

“This suggests that expectations had a rather deep effect, influencing how the brain processes pain,” said Jepma.

Surprisingly, their expectations also highly influenced their ability to learn from experience. Many subjects demonstrated high “confirmation bias” — the tendency to learn from things that reinforce our beliefs and discount those that don’t. For instance, if they expected high pain and got it, they might expect even more pain the next time. But if they expected high pain and didn’t get it, nothing changed.

“You would assume that if you expected high pain and got very little you would know better the next time. But interestingly, they failed to learn,” said Wager.

This phenomenon could have tangible impacts on recovery from painful conditions, suggests Jepma.

“Our results suggest that negative expectations about pain or treatment outcomes may in some situations interfere with optimal recovery, both by enhancing perceived pain and by preventing people from noticing that they are getting better,” she said. “Positive expectations, on the other hand, could have the opposite effects.”

The research also may shed light on why, for some, chronic pain can linger long after damaged tissues have healed.

Whether in the context of pain or mental health, the authors suggest that it may do us good to be aware of our inherent eagerness to confirm our expectations.

“Just realizing that things may not be as bad as you think may help you to revise your expectation and, in doing so, alter your experience,” said Jepma.

Using Virtual Reality in Beneficial Ways

Virtual reality is technology that’s advancing from being fringe to something that’s gradually becoming implemented more in the 21st century. This trend will only continue with lower costs of materials for virtualization and improved software.

The way virtual reality works is obvious enough — some sort of apparatus that covers the eyes and is able to transmit visual of a virtual world is required. Virtual worlds of course will have sounds to make them more immersive, and perhaps in the future there will be an option to stimulate other senses as well. It isn’t unreasonable to expect the possibility of VR technology that somehow provides the replication of smell, taste, and feel. Eventually there is likely to be VR technology with direct brain stimulation too.

Virtual reality is often presented these days as a fun way to spend time through gaming, and while it can be beneficial to provide people with an escape that doesn’t involve hard drugs in a world that’s often crazy and fucked up, virtual reality has other uses that deserve to be known about more.

One of the most notable recent findings is a study finding that people recall information better through virtual reality. Since knowledge is power, the enhanced ability of people to recall knowledge would be helpful in a variety of scenarios, such as training people for meaningful work, keeping fond memories more effectively, and assisting in educational endeavors. This could be combined with other research finding that drawing pictures is a strong way to remember information.

Most people are not especially good multi-taskers — the research tells us that only a few percent of people are “super taskers,” or those with the ability to focus on multiple tasks well. For whatever reason this is, it’s a general principle that human beings tend to perform better when their primary focus is on one task at a given time. Virtual reality thus provides an immersive environment that should allow people to focus more on one task than a traditional 2D learning environment.

VR has been shown to reduce the fear children have for needles in one study. This makes sense due to the distraction from VR’s intense immersion. Since the fear of needles is a suffocating one for some children, something as simple as a VR experience of going to an amusement park or a beach would be immensely helpful.

There’s a problem of too many people avoiding vital vaccinations in the United States, leading to diseases that should have been extinguished in the 20th century suddenly making recurrences in certain parts of the country. This is another example of how technology can be used to solve a real problem and protect society.

VR’s distraction could be extended to surgeries where local anathesia is used, thus protecting people from pain. It has already been found that virtual reality therapy is effective at reducing pain in hospitalized patients. It isn’t entirely clear why, but it may be because the VR experience is so immersive that the brain is unable to concurrently process the pain stimuli along with the VR.

It has been theorized that people have a fixed capacity for attention, and it has also been thought that when people are expecting physical pain in the immediate future, they tend to feel it more intensely. This may be because instead of the pain being a surprise, the increased focus on it before the pain hits may cause it to be felt more strongly.

Virtual reality will also have an important role in the journalism of the future. Studies have found that VR makes journalism more immersive, such as the VR story about factory farming being successful at raising more awareness of the horrific treatment often endured by animals.

VR can thus be an effective tool at fighting corruption and injustice in an era where young people generally — for whatever reason — are reading less than past generations. It has been found that too much use of fantasy-like elements in VR distract from the realism of the story and can make them less credible, however.

VR has also been referred to as an “empathy machine.” It’s conceivable that VR could be used for rehabilitation — use of the technology has already shown promise at increasing empathy levels, and VR shows promising mental health treatment results. The immersive virtual experience of owning a body in VR space has at times shown to really have an impact at altering perceptions and making important impressions.

In sum, while interactions in real life will always have importance that’s often most meaningful, there are many ways that virtual reality may improve the livelihoods of others.

Breakthrough in Making Much Less Addictive Opioids

Important research this is, for it shows that the powerful pain relief opioids provide doesn’t have to be such a dangerous double-edged sword.

In the US, more than one-third of the population experiences some form of acute or chronic pain; in older adults this number rises to 40 percent.

The most common condition linked to chronic pain is chronic depression, which is a major cause of suicide.

To relieve severe pain, people go to their physician for powerful prescription painkillers, opioid drugs such as morphine, oxycodone and hydrocodone.

Almost all the currently marketed opioid drugs exert their analgesic effects through a protein called the “mu opioid receptor” (MOR).

MORs are embedded in the surface membrane of brain cells, or neurons, and block pain signals when activated by a drug.

However, many of the current opioids stimulate portions of the brain that lead to additional sensations of “rewarding” pleasure, or disrupt certain physiological activities. The former may lead to addiction, or the latter, death.

Which part of the brain is activated plays a vital role in controlling pain. For example, MORs are also present in the brain stem, a region that controls breathing.

Activating these mu receptors not only dulls pain but also slows breathing. Large doses stop breathing, causing death.

Activating MORs in other parts of the brain, including the ventral tegmental area and the nucleus accumbens, block pain and trigger pleasure or reward, which makes them addictive. But so far there is no efficient way to turn these receptors “on” and “off” in specific areas.

But there is another approach because not all opioids are created equal. Some, such as morphine, bind to the receptor and activate two signaling pathways: one mediating pain cessation and the other producing side effects like respiratory depression.

Other drugs favor one pathway more than the other, like only blocking pain – this is the one we want.

“Biased opioids” to kill pain

But MOR isn’t the only opioid receptor. There are two other closely related proteins called kappa and delta, or KOR and DOR respectively, that also alter pain perception but in slightly different ways.

Yet, currently there are only a few opioid medications that target KOR, and none that target DOR. One reason is that the function of these receptors in the brain neurons remains unclear.

Recently KOR has been getting attention as extensive studies from different academic labs show that it blocks pain without triggering euphoria, which means it isn’t addictive.

Another benefit is that it doesn’t slow respiration, which means that it isn’t lethal. But although it isn’t as dangerous as MOR, activating KOR does promote dysphoria, or unease, and sleepiness.

This work suggests it is possible to design a drug that only targets the pain pathway, without side effects. These kind of drugs are called “biased” opioids.

[…]

The exciting news is that researchers in the Roth lab have discovered several promising compounds based on the KOR structure that selectively binds and activates KOR, without cavorting with the more than 330 other related protein receptors.

Now our challenge is to transform these molecules into safer drugs.

Study: Legal Medical Cannabis Lowers Opioid Use

The pharmaceutical industry is generally among the biggest opponents of legalized marijuana for a reason. Interestingly enough, legal marijuana now polls at 55 to 60 percent majority support in the United States. If the country was a democracy instead of mainly a plutocracy, issues with majority support such as that one would be acted on much differently than is done today.

States that have approved medical cannabis laws saw a dramatic reduction in opioid use, according to a new study by researchers at the University of Georgia.

In a paper published today in the Journal of the American Medical Association, Internal Medicine, researchers examined the number of all opioid prescriptions filled between 2010 and 2015 under Medicare Part D, the prescription drug benefit plan available to Medicare enrollees.

In states with medical cannabis dispensaries, the researchers observed a 14.4 percent reduction in use of prescription opioids and nearly a 7 percent reduction in opiate prescriptions filled in states with home-cultivation-only medical cannabis laws.

“Some of the states we analyzed had medical cannabis laws throughout the five-year study period, some never had medical cannabis, and some enacted medical cannabis laws during those five years,” said W. David Bradford, study co-author and Busbee Chair in Public Policy in the UGA School of Public and International Affairs. “So, what we were able to do is ask what happens to physician behavior in terms of their opiate prescribing if and when medical cannabis becomes available.”

[…]

The researches concede that if medical cannabis is to become an effective treatment, there is still much work to be done. Scientists are only just beginning to understand the effects of the compounds contained in cannabis, and an effective “dose” of cannabis would need to be defined clearly so that each patient receives a consistent dose.

“Regardless, our findings suggest quite clearly that medical cannabis could be one useful tool in the policy arsenal that can be used to diminish the harm of prescription opioids, and that’s worthy of serious consideration,” David Bradford said.

It should also be noted that marijuana can come with its own harms, particularly if smoked. Competent studies have consistently found for the last few years that marijuana smoke is about as harmful and perhaps even more harmful than tobacco smoke. In light of this, non-combustible alternatives such as the marijuana edibles should be recommended much more for those needing pain relief.

Study Finds Women Feel Less Pain When Holding the Hand of Someone They Love

There’s real evidence of the positive effects of caring human touch. Society is pained by many problems that it shouldn’t have, and an approach such as this one that isn’t opiate-based (seeing what that approach has done to society) should therefore be encouraged more.

A small team of researchers from the University of Colorado, the University of Haifa and University Paris Diderot has found that women sense less pain when holding the hand of a person they love. In their paper published in the Proceedings of the National Academy of Sciences, the group describes the experiments they conducted in which women were exposed to some degree of pain and were then asked to report how painful it felt under different conditions.

In modern times, it has become common in some countries for husbands (or other loved ones) to be invited into the to offer comfort as a woman experiences the pain of childbirth. But does such hand-holding actually offer any benefits to the woman in pain? To test for that possibility, the researchers enlisted the assistance of 20 couples willing to undergo several experiments.

The experiments consisted of having the women hold onto a tube through which could be pumped to induce pain. Then the women and their significant others were placed in different sorts of situations. In some, the man held the woman’s hand as the hot water was applied; in others, the man sat nearby but did not offer a hand. In others, the man sat in a nearby room. In all of the cases, both volunteers were asked to rate the degree of pain the woman was experiencing.

In looking at the results of their experiments, the researchers found that the women reported on average experiencing less than half as much pain when they were holding their loved one’s hand. And it went both ways—the men in the group were most accurate in matching the reported by the women when they were holding her hand during her painful experience. The team also found that couples whose EEG printout was most similar coincided with the lowest reports of pain by the women.

The researchers suggest that hand holding can offer two types of benefits to a person in pain. The first is that touching or being touched releases chemicals in the brain that make pain easier to bear. The second is that there appeared to be some sort of synchronizing going on in the brains of the couples that offered an analgesic-like effect, some of which, they note, might have an empathetic component.

Wife of a Former American Football Player on the Brain Damage Football Caused in her Husband and in Others

It’s surprising that this widespread brain damage among American football players receives as little attention as it does, especially with compelling essays such as this one.

Professional football is a brutal sport, he knew that. But he loved it anyway. And he accepted the risks of bruises and broken bones. What he didn’t know was that along with a battered body can come a battered mind.

For decades, it was not well understood that football can permanently harm the brain. Otherwise, many parents would most likely not have signed their boys up to play. But this reality was obscured by the N.F.L.’s top medical experts, who for years had denied any link between the sport and long-term degenerative brain diseases like C.T.E., chronic traumatic encephalopathy.

That started to change in late 2009 when, for the first time, the N.F.L. publicly acknowledged that concussions can have long-term effects. In 2016, a top league official admitted there is a connection between football and C.T.E. which has now been found in the brains of more than 100 deceased players. But for Rob, and countless other players, those admissions came too late.