Instruction in one form of self-hypnosis. Subjects can be taught to induce a state of profound relaxation through a series of simple exercises. Because autogenic training can help individuals modify physiological arousal, it is considered by some as a potential countermeasure against PDD. There is little data to support or refute this argument. Because autogenic training focuses on self-regulation of tonic levels of physiological activity, and conventional polygraphy relies on phasic response patterns, its usefulness in defeating modern PDD techniques is not expected to be high.