Habituation of Sexual Arousal in Sex Offenders : The Role of Cognitive Processes

Habituation of sexual arousal to deviant fantasy in a sample of sex offenders was examined. In addition self-reports of attentional and affective states were monitored to observe if changes in these states parallelled shifts in sexual arousal. Eight male sex offenders were presented with a constant deviant erotic fantasy described on audiotape. The same fantasy (habituation stimulus) was presented for 18 trials within a session followed by a different fantasy (novel stimulation) and then the habituation stimulus was presented again. Penile tumescence and subjective reports were used to measure sexual arousal. Skin resistance was recorded, as well as self-reports of how vivid the images were and how absorbed participants became in the depicted fantasy. A repeated measures analysis of variance showed that penile tumescence was the only dependent variable to vary significantly across habituation trials. Penile tumescence increased over trials and was higher at the end of the series than at the beginning. Attentional and affective responses did not change significantly or parallel the shifts in penile tumescence across the 18 trials of repeated stimulation. There were no increases in penile tumescence during novel stimulation or following the reintroduction of the original fantasy. These results contrast with those reported by Kounkounas and Over (1993) for nonoffenders of decreases rather than increases in sexual arousal paralleled by shifts in attentional and affective states. The discrepant findings are discussed with reference to the role of cognitive processes and the possibility that there are fundamental differences in the way sex offenders and nonoffenders process the information in erotic fantasy.