Stress

Hypersensitivity

As our first line of defense, skin must respond to stresses that are constantly changing. While researching how best to protect the skin of leprosy patients, I gained great admiration for skin’s adaptive properties.

We developed a mechanical device that presses a metal rod against the fingertips with measured force. If I put my hand under the tiny hammer, it feels rather pleasant, like a vibromassage. But if I let the machine run on for several hundred beats, my finger turns slightly red and feels uncomfortable. After fifteen hundred beats I must pull my finger out, for I can no longer bear the pain. When I return to the machine the next day, I can only tolerate a couple of hundred beats before yanking my finger away.

Mild inflammation brings on a condition called hypersensitivity. My finger feels warm as blood surges to the point of stress, and swollen as the body cushions it with extra fluid. The same finger that endured many blows from a tiny hammer yesterday has become hypersensitive, and in its inflamed state just a few more thumps could lead to a blister or ulcer.

Likewise, a burned finger becomes hypersensitive to heat. More than once I have put my hands in a basin only to discover that my hands are sending mixed signals. My left hand reports that the water is hot while my right hand says warm. Then I remember an incident from breakfast: a drop of hot bacon grease popped out of the pan and landed on my left hand. Nerve endings at that spot lowered their tolerance threshold and are now reporting warm water as hot because even a little heat might harm the mildly inflamed tissues.

Who has not felt the irritation of a sore finger always seeming to get bumped every few minutes no matter how careful you are. That phenomenon has a sound physiological basis: pain cells near the site of injury have become ten times more sensitive to pain. In effect, pain cells “turn up the volume” so that I won’t foolishly subject my skin to more hot grease or hammer blows. In these remarkable ways, hypersensitivity produces a shield of protection around vulnerable areas.

At times all of us experience a psychological form of hypersensitivity. An accumulation of small stresses builds up — overdue bills, work pressures, house repairs, irritating habits of family members — and suddenly every minor frustration hits like a sledgehammer. Pain, whether physical or emotional, works precisely because it is loud and insistent. Hypersensitivity alerts the body to skin’s urgent need of relief from stress. Likewise, emotional hypersensitivity in one member can alert the larger community to the need for respite or outside care.

A healthy body feels the pain of its weakest parts. We may be called on to bolster a bruised ego, mediate a dispute, or take upon ourselves some of the minor stresses that have piled on others. As a former missionary, I cannot overstate the life-sustaining role of people back home who supported me by praying and writing letters. These unusually sensitive cells in the "body" sought out my hardships and nourished me in times of need. Such dedicated people make the difference between a missionary or aid worker who serves twenty years and one who breaks down after a short time.

A psychologist walked towards the podium while teaching stress management to a knowledgeable audience. As she lifted a glass of water, everyone expected the question to be "is the glass half empty or half full?". Instead, with a smile on her face, she asked: "How much does this glass of water weigh?"

Answers were heard from the audience ranging from 8 ounces to 20 ounces.

She replied: "Absolute weight doesn't not matter. It depends on how long I hold it. If I hold it for a minute, this isn't a problem. If I hold it for an hour, I will have pain in my arm. If I hold it for a whole day, my arm will feel numb and paralyzed. In each case, the weight of the glass does not change, but the longer I hold it, the heavier it becomes."

She continued: "Stress and worries in life are like this glass of water. Think about it for a while and nothing happens. Think about it a little longer and they start to hurt. And if you think about it all day, you feel paralyzed – unable to do anything".

"It's time to put down your glass."