Sensory deprivation has been a blog topic and is mentioned by Stieg Larsson who notes that:
it is inhumane according to the Geneva Convention;
dictatorships have used it for brainwashing;
it may have been inflicted on the prisoners in the Moscow show trials.
Thus, there is a parallel between an alien prisoner of Dominic Flandry and Larsson's Lisbeth Salander. However, Lisbeth is confined in a room free of stimuli, containing only a bed and a restraining belt. Inhumane though this is, I question whether she is right to equate it with sensory deprivation in the full sense.