Ryuta Idogawa traces the onset of his battle with mental illness to a moment not long after his parents had been relocated to Saitama from their hometown of Futaba, Fukushima Prefecture, in the spring of 2011.

Idogawa recalls with almost claustrophobic clarity how, as he boarded a train to travel to Tokyo, a sense of panic set in when the carriage walls seemed to close in and fellow passengers in the rush-hour squash started to stare — piercing, even accusatory stares, he thought.

"I was sweating, but I felt really cold and my heart was racing, faster and faster," says Idogawa, 33. "I could hardly breathe. I thought, 'Oh My God! I'm going to die.'"