"Long before it's in the papers"
January 27, 2015


Torture permanently damages normal pain perception, study finds

Nov. 7, 2013
Courtesy of American Friends
of Tel Aviv University
and World Science staff

Tor­ture can per­ma­nently dam­age the nor­mal per­cep­tion of pain, ac­cord­ing to a study of Is­rae­li sol­diers cap­tured dur­ing the 1973 Yom Kip­pur War.

The sol­diers were sub­jected to bru­tal tor­ture in Egypt and Syr­ia. Held alone in ti­ny, filthy spaces for weeks or months, some­times hand­cuffed and blind­folded, they suf­fered se­vere beat­ings, burns, elec­tric shocks, starva­t­ion, and worse. And rath­er than re­ceiv­ing treat­ment, ad­di­tion­al tor­ture was in­flicted on ex­ist­ing wounds.

For­ty years lat­er, re­search by Ruth De­frin at Tel Aviv Uni­vers­ity has found that the ex-pris­on­ers con­tin­ue to suf­fer from dys­func­tional pain per­cep­tion and regula­t­ion. The study is pub­lished in the Eu­ro­pe­an Jour­nal of Pain.

“The hu­man bod­y’s pain sys­tem can ei­ther in­hib­it or ex­cite pain. It’s two sides of the same coin,” said De­frin. “Usu­ally, when it does more of one, it does less of the oth­er. But in Is­rae­li ex-POWs, tor­ture ap­pears to have caused dys­func­tion in both di­rec­tions. Our find­ings em­pha­size that tis­sue dam­age can have long-term sys­temic ef­fects and needs to be treated im­me­di­ate­ly.”

The study fo­cused on 104 com­bat vet­er­ans. Six­ty of the men were tak­en pris­on­er dur­ing the war, and 44 of them were not. In the stu­dy, all were put through a bat­tery of psy­cho-phys­i­cal pain test­s—ap­ply­ing a heat­ing de­vice to one arm, sub­merg­ing the oth­er arm in a hot wa­ter bath, and press­ing a ny­lon fi­ber in­to a mid­dle fin­ger. They al­so filled out psy­chological ques­tion­naires.

The re­search­ers found that the ex-POWs showed di­min­ished pain in­hib­ition (the de­gree to which the body eases one pain in re­sponse to anoth­er) and height­ened pain ex­cita­t­ion (the de­gree to which re­peat­ed ex­po­sure to the same sensa­t­ion height­ens the re­sult­ing pain). 

It’s not en­tirely clear wheth­er the dys­func­tion is the re­sult of years of chron­ic pain or of the orig­i­nal tor­ture it­self, they added, but a sta­tis­ti­cal anal­y­sis of the test da­ta sug­gested that be­ing tor­tured had a di­rect ef­fect.

* * *

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Torture can permanently damage the normal perception of pain, according to a study of Israeli soldiers captured during the 1973 Yom Kippur War. The soldiers were subjected to brutal torture in Egypt and Syria. Held alone in tiny, filthy spaces for weeks or months, sometimes handcuffed and blindfolded, they suffered severe beatings, burns, electric shocks, starvation, and worse. And rather than receiving treatment, additional torture was inflicted on existing wounds. Forty years later, research by Ruth Defrin at Tel Aviv University has found that the ex-prisoners continue to suffer from dysfunctional pain perception and regulation. The study is published in the European Journal of Pain. “The human body’s pain system can either inhibit or excite pain. It’s two sides of the same coin,” said Defrin. “Usually, when it does more of one, it does less of the other. But in Israeli ex-POWs, torture appears to have caused dysfunction in both directions. Our findings emphasize that tissue damage can have long-term systemic effects and needs to be treated immediately.” The study focused on 104 combat veterans. Sixty of the men were taken prisoner during the war, and 44 of them were not. In the study, all were put through a battery of psychophysical pain tests — applying a heating device to one arm, submerging the other arm in a hot water bath, and pressing a nylon fiber into a middle finger. They also filled out psychological questionnaires. The researchers found that the ex-POWs showed diminished pain inhibition (the degree to which the body eases one pain in response to another) and heightened pain excitation (the degree to which repeated exposure to the same sensation heightens the resulting pain). It’s not entirely clear whether the dysfunction is the result of years of chronic pain or of the original torture itself, they added, but a statistical analysis of the test data suggested that being tortured had a direct effect.