David Mitchell remembers the day he read the memoir of a 13-year-old boy with autism - hailing it a "revelatory godsend" that offered a window on the life of his own autistic son.

The best-selling author of Cloud Atlas says Naoki Higashida was "one of the most helpful and practical writers on the subject of autism in the world".

"Pre-Naoki, I'm ashamed to say that I used to regard and treat my son as a kind of defective robot," Mitchell says.