The Star Rover by Jack London

In THE STAR ROVER (published in the UK as THE JACKET), Darrell Standing, a university professor serving life imprisonment in San Quentin for murder, defies the will of prison officials who try to break his spirit with "the jacket." The jacket is a hellish canvas straitjacket which can be tightly laced so as to compress the whole body. To survive, Standing discovers how to enter a trance state in which he walks among the stars and experiences past lives.