BBC News - Forty years in solitary confinement and counting

As two men in Louisiana complete 40 years in solitary confinement this month, the use of total isolation in US prisons is on the rise. What does this do to a prisoner's state of mind?
Robert King paces the front room of his small, one-storey house in Austin, Texas.
"I imagine I could put my cell inside this room about six times," he says. "Probably more."
For 29 years Robert King occupied a cell nine feet by six - just under three metres by two - for at least 23 hours a day.
He spent most of his time incarcerated in one of the toughest prisons in the United States - Louisiana State Penitentiary.
The prison, the largest in the US, is nicknamed Angola after the plantation that once stood on its site, worked by slaves shipped in from Africa. King, who was released from prison in 2001, still calls himself one of the Angola Three - three men who have been the focus of a long-running international justice campaign.

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