Can We Measure Sexual Interest in Pedophiles Using a Sexual Distractor Task

Indirect measures of deviant sexual interest have yielded interesting and promising in the field of pedophilic interest. However, further research is needed. A lot of indirect measures are still at the developmental stage regarding clinical application. They do not reach appropriate psychometric criteria or are not yet sufficiently tested for susceptibility to manipulation or deception. Furthermore, for some paradigms, the exact mechanisms underlying the attentional processes are still under discussion. This study aimed to measure sexual interest under cognitive load. With this challenging active task subject’s possibility to manipulate their response to the sexual stimuli should be lower than in easier tasks and in passive designs. Twenty-two pedophiles, seven forensic control subjects and 50 healthy men performed cognitive tasks. Simultaneously, sexually relevant and sexually non-relevant distractors were presented. Meanwhile, their cognitive performance and eye movements were assessed. As expected healthy subjects showed a certain impairment of cognitive performance when sexually relevant distractors were presented to them. They took significantly more time to look at sexual adult distractors than at sexual child distractors. In contrast, both forensic groups performed much poorer than the healthy control group without specificity for certain sexual distractors. While forensic control subjects tended to view adult stimuli longer than those of children, no differences were found for pedophiles. The age preference index for the fixation time differentiated moderately between pedophiles and non-pedophiles. Our design worked well with healthy subjects. Further studies should examine if an individual adaptation of the task difficulty could help to find the expected cognitive performance impairments of pedophiles and forensic subjects when they are presented with certain distractor categories.