In a study which has examined forms of ill treatment during captivity, researchers have found that psychological torment and humiliation can inflict as much terror and trauma as physical torture.

The study was carried out by psychologists at King's College, University of London, and the Clinical Hospital Zvezdara in Belgrade, on 279 former prisoners from the former Yugoslavia including Bosnians, Croatians and Serbians.

All had experienced at least one form of physical torture such as beatings as well as mental torture, and of the 241 men, 192 had been in detention camps, with the torture experiences occurring roughly eight years earlier.

The men were asked which of 54 war-related stressors and 46 different forms of torture they had experienced and how distressed or out of control they felt overall during the torture.

The researchers say it was hard to distinguish between the psychological damage exerted by mental versus physical forms of torture.

The study authors say the findings indicate a need for a broad definition of torture, because techniques such as sham executions, threats of rape, sexual advances, humiliating treatment, sleep deprivation and witnessing the torture of others, were as distressing as physical torture.

The authors say the unpredictability and loss of control created by mental torture can produce similar levels of anxiety, fear and helplessness as physical torture and leave comparable long-term psychological scars.

The findings come at a time when interrogation techniques have stirred controversy in the United States after evidence has emerged of detainee abuse in Guantanamo Bay, Iraq and Afghanistan, and revelations that the CIA ran secret prisons outside the the United States for terrorism suspects.

Study author Metin Basoglu of King's College says the United Nations define torture as severe pain or suffering, whether physical or mental.

However the U.S. torture policy appears to advocate a narrower definition of torture that excludes mental pain and suffering caused by various acts that do not cause severe physical pain.

It excludes detention and interrogation procedures which include blindfolding and hooding, forced nudity, isolation and psychological manipulations.

Based on the detainees' scoring of how stressful each method of torture was, and the incidence of mental illness and post-traumatic stress disorder resulting from the experience, the authors say there was no substantial difference between mental and physical torture.

In an accompanying editorial Dr. Steven H. Miles, of the University of Minnesota, Minneapolis says the distinction between torture and degrading treatment is not only useless, but also dangerous.

Dr. Miles says the study demonstrates that the severity of long-lasting adverse mental effects is unrelated to whether the torture or degrading treatment is physical or psychological.

According to Dr. Miles the wrongness of the inflicted harms is compounded by the fact that most abused prisoners, including those in the present war on terror, are innocent or ignorant of terrorist activities, but guilty or innocent, torture survivors rarely get the mental health treatment they need.

Dr. Miles urges human rights–respecting nations and medical societies to unite to reinforce international authority against torture.