Neurofunctional correlates of sexual arousal are of interest in basic research as well as in clinical science. In forensic psychiatry, it is important to use designs which are potentially robust against susceptibility to manipulation or deception. We tested a new design to measure neurofunctional correlates of sexual preference. Twenty-two healthy heterosexual men had to solve a mental rotation task while sexually preferred or non-preferred distractors were presented simultaneously. With this challenging active task, subjects' possibility to manipulate their response to the sexual stimuli should be lower than in easier tasks and in passive designs. Participants needed more time to solve the mental rotation task when distractors of women and girls were presented compared to distractors of men and boys. FMRI-results showed a network of three brain regions which specifically responded to sexually preferred distractors. Female and adult distractors evoked stronger responses than male and child distractors in regions comprising parahippocampal/fusiform gyrus and amygdala/basal ganglia/thalamus, respectively. Women distractors elicited stronger responses in the inferior parietal lobe compared to all other distractors. Specifically, sexually preferred distractors elicited a weaker downregulation than other distractors. We suppose a different emotion regulation with respect to the sexual relevance of the distractors. To our knowledge, this study is the first to show neurofunctional correlates of sexual preference under cognitive demand. Further studies should examine whether this design is more robust against susceptibility to manipulation than others, in order to be applied as a measurement of sexual preference in forensic patients.
Keywords: Attention allocation; Cognitive load; Distractor; Emotion regulation; Forensic psychiatry; Mental rotation; Sexual interest; Sexual preference.