In what ways are Louie and Phil treated differently by each group of Japanese they meet in the early days of their imprisonment? (unbroken by Laura Hillenbrand)

After being caught in Japanese waters, and taken prisoners, Louie and Phil were treated nicely and with respect while on the ship, good food and treats, medical care and so on; they even were untied from time to time. But while off the ship on Execution Island they were brutally handled and physically abused, they were put in small cells, no medical care and with meager food, no dignity neither humanity.