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Courtesy of Jessica Palmer, Biophemera



Jeanna Bryner,

A social snub can deliver a seemingly painful blow. Now, it turns out that sting may be real. A gene linked with physical pain is also associated with a person’s sensitivity to rejection, a new study finds.

The discovery doesn’t suggest that being chosen last for a pick-up ball game, say, will send you limping off the field. Rather, a rare form of the so-called mu-opioid receptor gene (OPRM1) is likely involved in the emotional aspect of physical pain — essentially, how much a person is bothered by a throbbing leg, for instance.

In the study, 122 participants indicated how much they agreed or disagreed with statements, such as “I am very sensitive to any signs that a person might not want to talk to me.” Their saliva was also analyzed for OPRM1. (People with a rare form of OPRM1 experience more physical pain than others.)

Then, the researchers used functional magnetic resonance imaging (fMRI) to scan the brains of 31 of the participants during a virtual ball-tossing game. Initially, each participant was included with two virtual players before being excluded when the virtual players stopped throwing the ball to them.

Individuals with the rare OPRM1 variant were more sensitive to social rejection. The mutant-gene carriers also showed more activity in brain regions linked with physical and social pain, including the dorsal anterior cingulate cortex and anterior insula.

Such social pain may have benefited our ancestors. “Because social connection is so important, feeling literally hurt by not having social connections may be an adaptive way to make sure we keep them,” said study researcher Naomi Eisenberger of UCLA.

She added, “Over the course of evolution, the social attachment system — which ensures social connection — may have actually borrowed some of the mechanisms of the pain system to maintain social connections.”

More here.

JM Livengood,

The author, a psychologist in a pain control center, was asked by the editor of The Clinical Journal of Pain to relate her personal experience with neuropathic pain. Her chronic pain began six years previously when her car was rear-ended by a large tractor-trailer truck. After several weeks of traction, rest, and a cervical collar, healing began. One year later she was re-injured in a fall and in addition to the cervical injury also injured her lumbar spine. She experienced right upper and lower extremity numbness, loss of fine motor skills in the right hand, and difficulty walking. Despite her neurosurgeon’s urging to maintain strict bed rest for two months, she put herself on a walking program to prevent muscle atrophy. She continued to have chronic pain with occasional flare-ups.

Several months later, in the process of building a patio lounge chair, her already weakened spine was again injured. She required surgery, including a fusion at C4-5, along with removal of a ruptured disc and removal of several fragments from the spinal canal. Presurgical nerve damage caused prolonged motor weakness and numbness. Also, when the bone graft was removed from the iliac crest, injured nerves left her with neuropathic pain in the left thigh and leg. During the subsequent healing months, the author learned personally about definitions of complex regional pain syndrome (CRPS), allodynia, dysesthesia, hyperesthesia, and about listening to patients in pain and believing their story. She discusses several “do’s and don’ts” for surgeons and for patients, related to her personal experience. Probably the most valuable advice for pain management professionals is to listen to your patients. Ask them what is wrong and they will tell you. It is common to ask patients questions which relate to the experience of chronic pain, but do not seem to relate to CRPS symptoms. For example, “When is your pain worse?” “What positions worsen pain?” While these activities do relate to chronic pain, there is no mention of experiences that affect neuropathic pain such as encountering a sudden blast of water while in the shower, walking into an air conditioned room, or walking outside on a windy day. Also, questionnaires contain descriptions of chronic pain symptoms but not CRPS symptoms such as crawling ants, stinging bees, and soft cotton being rubbed across one’s skin. The author describes the feeling of cold air from air conditioning or wind contacting her skin feeling like lightning-sharp goose bumps like cactus spikes. She experienced an intense burning, stinging sensation as though a swarm of angry yellow jackets was stinging profusely and unrelentingly. Areas of her skin felt hot and cold simultaneously. She had a feeling of soft puffs of cotton containing shards of razor-sharp steel being rubbed agonizingly slowly over her skin where the bone graft was taken. Also, she described a feeling of a soft feather being rubbed tortuously slowly and softly over her skin. These are symptoms which the author feared no one would believe if she actually described how they felt.

As a psychologist, she never actually disbelieved, but did doubt patients who told her they hurt too badly to comply with their relaxation and visual imagery exercises. She never disbelieved, but did doubt patients who reported that their pain “moved” or increased after receiving a nerve block. As a patient, she learned what they meant.

She emphasizes the importance of treating patients with empathy, respect, and explanations of treatments. One of the most beneficial things she gained by being a patient is to listen to her patients and try to actually hear what they are telling her, instead of listening for what she thinks the patients should say in order for her to impose a known treatment on a familiar sounding problem. She believes persons stereotyped as “professional” patients may simply be patients seeking professional help.

Journal: Clin J Pain, 12(2):90-93, 1996. 0 References Vanderbilt Pain Control Center, 401 Medical Arts Bldg., 1211 21st Ave., South, Nashville, TN 37232 (Dr JM Livengood) JAC.03 OC9608/278 ©1996.


Claudia Campbell,

Pam and John are currently in physical therapy following similar car accidents. They both are receiving therapy for strained necks. However, Pam appears more “down” and catastrophizes that her physical therapy sessions are more painful than helpful. John, on the other hand, routinely trades jokes with his physical therapist during each session and remarks positively on the improvements to his health and functioning. Why do these two patients have such different responses to pain, and are their responses linked to their personalities or their gender?

A variety of characteristics, from genetics to psychosocial processes, contribute to how people perceive pain. A person’s sex (a more biologically-driven term)/gender (a sociocultural term) emerged as a critical factor in shaping the experience of pain. Over the last 15 years an explosion of research has documented differences between how men and women respond to pain and analgesic medications meant to reduce pain (see Greenspan et al., 2007 for a comprehensive review).

Women are more likely than men to report acute and chronic pain, and they use pain-relieving medication more often, even when equating for pain severity. Women also have greater prevalence (in many cases, 50-100% higher relative to men) of many chronic pain conditions including headache, temporomandibular joint disorder (TMD), fibromyalgia, irritable bowel syndrome, and arthritis8, and they report greater pain than men in experimental models, where healthy individuals undergo standard noxious stimuli2.

A number of psychosocial and interpersonal variables also contribute to pain; a few of the well-studied factors include age, race/ethnicity, mood, and coping. A great deal of study has focused on catastrophizing, a maladaptive coping strategy characterized by a negative cognitive and affective response to pain (like feelings of helplessness, magnification, and ruminative thoughts about pain), which is more common in women. Sex differences in catastrophizing may mediate the difference between men and women with chronic pain and in experimental settings1. Similarly, depressive symptoms are more frequently reported by women and have been found to predict future musculoskeletal disorders like low back pain.

More here.

Emanuel Derman, The Edge

But what is happiness? In The Ethics, written in 1677, Spinoza ambitiously tried to do for the emotions what Euclid did for geometry. Euclid began with ‘primitives’, his raw material, the elements that everyone understands. In geometry, these were points and lines. He then added axioms, self-evident logical principles that no one would argue with, stating for example that ‘If equals are added to equals, then the wholes are equal’. Finally, he proceeded to theorems, interesting deductions he could prove from the primitives and the axioms. One of them is Pythagoras’ theorem that relates triangles to squares: the sum of the squares of the sides of right-angled triangle are equal to the square of the hypotenuse.

Spinoza approached human emotions the way Euclid approached triangles and squares, aiming to understand their inter-relations by means of principles, logic and deduction.

Spinoza’s primitives were pain, pleasure and desire. Everyone who inhabits a human body recognizes these feelings. Just as financial stock options are derivatives that depend on the underlying stock price, so more complex emotions depend on these three primitives pain, pleasure and desire.

More here.  

By Madison Park, CNN

Despite two injections of anesthetic, Amy Anderson felt like her dentist was jamming rods into her tooth during a root canal. She writhed in pain as her infected tooth was hollowed with a drill, its nerve amputated, and then sealed.

“I knew this time something was wrong. I could feel my lips,” said the Syracuse, New York, resident, who told her dentist the drugs weren’t working.

Her doctor kept assuring her she had given her a proper dose and said: “I’m almost done.”

“I was hurting so bad, I was hitting myself in the stomach,” said Anderson, a redhead. “I almost wanted to hit her.”

Studies have indicated that redheads may be more sensitive to pain and may need more anesthetics to numb them.

New research published in this month’s Journal of American Dental Association found that painful experiences at the dentist might cause more anxiety for men and women with red hair, who were twice as likely to avoid dental care than people with dark hair. 

“Redheads are sensitive to pain,” said Dr. Daniel Sessler, an Outcomes Research Department chair at The Cleveland Clinic, in Cleveland, Ohio, who is one of the authors.

“They require more generalized anesthesia, localized anesthesia. The conventional doses fail. They have bad experiences at the dentist and because of the bad experiences, they could avoid dental care.”

Sessler, an anesthesiologist, began studying redheads’ sensitivity to pain after hearing chatter from colleagues.

“The persistent rumor in the anesthesia community was that redheads were difficult to anesthetize,” Sessler said. “They didn’t go under, had a lot of pain, didn’t respond well to anesthesia. Urban legends usually don’t start studies, but it was such an intriguing observation.”

This led to two studies. In 2004, research showed that people with red hair need 20 percent more general anesthesia than blonds and brunettes.

A 2005 study indicated that redheads are more sensitive to thermal pain and are more resistant to the effects of local anesthesia.

Researchers believe variants of the melanocortin-1 receptor gene play a role. This MC1R gene produces melanin, which gives skin, hair and eyes their color.

While blond, brown and black-haired people produce melanin, those with red hair have a mutation of this receptor. It produces a different coloring called pheomelanin, which results in freckles, fair skin and ginger hair. About 5 percent of whites are estimated to have these characteristics.

While the relationship between MC1R and pain sensitivity is not entirely understood, researchers have found MC1R receptors in the brain and some of them are known to influence pain sensitivity.

Non-redheads can also carry a variant of the MC1R gene. In this dental study that had 144 participants, about a quarter of the non-redheads had variants of the MC1R gene. These people also experienced heightened anxiety and avoided dental care compared with others who did not have the variant.

More here.

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