Filled versus empty intervals in prospective hypnotic time estimation with a real-simulator design

While interest in hypnotic time perception dates back to the 19th century (St. Jean, 1989) only recently have researchers focused on hypnosis and time estimation under more controlled conditions. Following the work of Jasinski (1986) and Mozenter and Kurtz (1992) we predicted a 2-way interaction between Group (high hypnotizable, low hypnotizable, and simulator) and Condition (waking, hypnotized) across 3 time intervals (30, 60, and 120 seconds). It was further hypothesized that "filled" intervals (with white noise) would be perceived as longer than "empty" intervals across all conditions. Sixty-two undergraduates were screened on the Stanford Hypnotic Susceptibility Scale: Form C and verbally estimated time intervals of 30, 60, and 120 seconds, 5 times each, both while in a waking and a hypnotic condition. Support was found for the predicted 2-way interaction for women only. High hypnotizable women showed a significant increase in overestimation from the waking to hypnosis condition, men did not. The predicted difference between "filled" versus "empty" intervals was not found.