Three women believed to have been abducted as teenagers have been found alive in a house in Cleveland, Ohio.
Amanda Berry, Gina DeJesus and Michelle Knight all went missing around a decade ago.
ITV News asked psychiatrist Dr Neel Burton what the psychological impact could be for the three women after their ordeal.
It is possible to envisage one or all three of the women suffering from an apparently paradoxical psychological reaction that the criminologist and psychiatrist Nils Bejerot baptised 'Stockholm Syndrome' after the events that took place during a bank robbery in Stockholm, Sweden, in 1973.
Jan Erik Olsson, a prisoner on leave, entered a branch of Kreditbanken with the intention of robbing it. When police followed in, he opened fire and injured one policeman.
A hostage situation ensued: for six days, from August 23 to August 28 1973, Olsson held four bank employees at gunpoint in the bank's main vault.
Olsson demanded, among others, that his friend and old cellmate Clark Olofsson join his operation; once within the bank, Olofsson established a communication link with police negotiators who, despite hearing death threats and screams, refused to let the comperes escape with the hostages.
Eventually, the police drilled a hole into the vault from the apartment above and launched a gas attack. Soon after, Olsson and Olofsson surrendered without any of the hostages being seriously injured.
But the strange thing is this: After some time in the vault, the hostages began to form an emotional attachment with their captors. They reported fearing the police more than their captors, and, after their release, they refused to testify against Olsson and Olofsson and set up a fund to cover their legal defense fees.
Olofsson claimed that he had not been aiding Olsson but merely trying to contain the situation and safeguard the hostages, and so had his convictions quashed by the court of appeal.
He became friendly with one of the hostages, Kristin Ehnemark; they met occasionally and even their families became friends.
Another notorious case of Stockholm Syndrome is that of millionaire heiress Patty Hearst, who on February 4, 1974, at the age of 19, was kidnapped from her apartment in Berkeley, California by a left-wing urban guerrilla group calling itself the Symbionese Liberation Army (SLA).
On April 3 Hearst announced on an audiotape that she had joined the SLA under the pseudonym of ‘Tania', and on April 15 she was photographed wielding an M1 carbine while robbing a bank in San Francisco.
When she was eventually arrested, she listed her occupation as ‘urban guerilla' and asked her attorney to ‘tell everybody that I'm smiling, that I feel free and strong and I send my greetings and love to all the sisters and brothers out there'.
After almost two years in prison, Hirst had her sentence commuted by President Jimmy Carter; on January 20, 2001, President Bill Clinton granted her a full Presidential Pardon in his last official act before leaving office.
Most of human history has been played out in hunter-gatherer societies in which abductions, particularly of women and their dependent children, must have been a very common occurrence.
Thus, it is possible to envisage that the capture-bonding psychological response exhibited by Kristin Ehnemark, Patty Hearst, and countless others is not just an ego defense, but also an adaptive trait that promotes survival in times of war and strife.
In fact, an inverse of Stockholm Syndrome called ‘Lima Syndrome' has been proposed, in which abductors develop sympathy for their hostages.
On December 17, 1996 members of the Túpac Amaru Revolutionary Movement took hostage hundreds of people attending a party to celebrate the birthday of Emperor Akihito at the official residence of the Japanese ambassador to Peru.
But within a few hours the captors had released most of the hostages, including even the most valuable ones.
- Dr Neel Burton, psychiatrist and author of Hide and Seek: The Psychology of Self-Deception.