During this procedure, the subject was seated in a reclining chair located in a private room equipped with an intercom. The audiovisual stimulus materials were presented via headphones on a 14-inch television monitor. Stimulus presentation and collection of penile, galvanic skin response (GSR), and respiration data were recorded and coordinated by a microprocessor-based Monarch Data Recording Device (DRD) (Behavioral Technology, Inc., Salt Lake City, Utah).