Belfast Crown Court was told Mark Whittley (20) cannot remember subjecting William Corry (13), to an ordeal during which electrodes were put in his mouth.
The boy was also punched and beaten with a sword during the attack at Whittley's home in Egmont Gardens on July 13th last year.
Whittley told police he could not remember carrying out the attack with another man because he had been on a two week drinking binge.
Judge Jack Petrie sent him to a psychiatric hospital with an indefinite restriction order.