Tuesday, March 29, 2011

The Physiology of a Broken Heart

"The course of true love never did run smooth."

~William Shakespeare, A Midsummer Night's Dream

A recently published study in the Proceedings of the National Academy of Sciences has confirmed what we, and legions of poets, playwrights and troubadours have known all along—that being dumped hurts. Hurts like your heart is being ripped out. Literally.

Researchers at the University of Michigan, Ann Arbor, studied 19 men and 21 women, all of whom had experienced an unwanted breakup within the past six months. Brain imaging (MRI) scans were used to map each subject's response during two painful tasks. In the Physical Pain Task, participants experienced the application of painful and non-painful heat to their left forearm. In the Social Rejection Task, participants first viewed a photo of a friend while recalling a positive experience. Next, they viewed a headshot of their ex-partner as they recalled being rejected. Through MRI scans, researchers demonstrated that rejection and physical pain stimulated shared regions of the brain.

And how, one might ask, could one volunteer for such a lively experiment?
"Participants were recruited via flyers posted...on Facebook and Craig's List. All participants were right-handed (recall the burning left forearm) and received $175 for their participation."
That must have been a hellova flyer.

All joking aside, the study furthers our understanding of how we process pain in the complex somatosensory cortex, with implications for the management of chronic pain. A. D. "Bud" Craig, principal investigator/director at the Atkinson Pain Research Laboratory, describes how pain is processed when we stub our toe:
"Sensory neurons flash a message to the spinal cord, spinal cord neurons relay the message to the brain, and the brain decides (a) damage has occurred, (b) it has been inflicted on the toe, and (c) something needs to be done (we start hobbling, raise the foot, utter an expletive). It may feel as if our toe is throbbing, but the experience is all contained within a mental projection of the condition of our toe within our brain."
Thus pain, as explained by Dr. Donald A. Ranney, is not a sensation, but a perception:
"This perception is real, whether or not harm has occurred or is occurring. Cognition is involved in the formulation of this perception. There are emotional consequences, and behavioral responses to the cognitive and emotional aspects of pain."

"Love is the triumph of imagination over intelligence."

~Henry Louis Mencken
This perception of pain brings me back to love, for what condition is more prone to misperception? From heart to lips and ears to heart, we stumble in love—and this is where my science-loving mind deviates from the U-M study. Something lacks in comparing a scalded forearm to a broken heart. You don't pine for a forearm—your heart won't race, your breath won't quicken—and you don't plan your life and future around it. Certainly, you won't be grieving six months later over the minor discomfort you suffered for answering the university's Craig's List ad.

How does one explain the physical symptoms—the chest pain, palpitations and shortness of breath— of heartbreak? According to Robert Emery and Jim Coan, professors of psychology at the University of Virginia,
"Emotional pain involves the same brain regions as physical pain...the anterior cingulate cortex may respond by increasing the activity of the vagus nerve—the nerve that starts in the brain stem and connects to the neck, chest and abdomen. When the vagus nerve is overstimulated, it can cause pain and nausea."
This association of physical pain with emotional pain may be related to the survival of our species. Whether on the Pleistocene savannah or in New York City, we thrive in social groups, with friends and family to watch our backs. As Naomi Eisenberger at UCLA explains,
"The social attachment system is piggy-backed onto the physical pain system to make sure we stay connected to close others. Being wrenched from another or rejected by a group is painful, so we avoid it."
The problem arises when emotional pain persists. An inability or unwillingness to move through the stages of bereavement can progress to what neuroscientist Mary Frances O'Connor calls "complex grief":
"They experience a lot of bitterness and anger, that their future is senseless. They don't adapt with time as others do."
Like physical pain, emotional pain can lead to chronic, debilitating heartbreak.

"You say that love is nonsense.... I tell you it is no such thing. For weeks and months it is a steady physical pain, an ache about the heart, never leaving one, by night or by day; a long strain on one's nerves like toothache or rheumatism, not intolerable at any one instant, but exhausting by its steady drain on the strength."

~Henry Brooks Adams

©2011 Tammy Yee

No comments:

Post a Comment



Copyright ©2016 Tammy Yee
All rights reserved. No portion of this web site may be reproduced without prior written consent.