Sexual affordances, perceptual-motor invariance extraction and intentional nonlinear dynamics: sexually deviant and non-deviant patterns in male subjects.

Sexual arousal and gaze behavior dynamics are used to characterize deviant sexual interests in male subjects. Pedophile patients and non-deviant subjects are immersed with virtual characters depicting relevant sexual features. Gaze behavior dynamics as indexed from correlation dimensions (D2) appears to be fractal in nature and significantly different from colored noise (surrogate data tests and recurrence plot analyses were performed). This perceptual-motor fractal dynamics parallels sexual arousal and differs from pedophiles to non-deviant subjects when critical sexual information is processed. Results are interpreted in terms of sexual affordance, perceptual invariance extraction and intentional nonlinear dynamics.

The neuropsychology and neurology of sexual deviance: a review and pilot study.

Current neurological hypotheses of paraphilia posit that sexual deviance is associated with frontal and/or temporal lobe damage. This broad conception is based on few investigations, however, and the first goal of this study was to review the existing data derived from neuropsychiatry, neuroimaging and neuropsychology. It is concluded that although fronto-temporal dysfunctions are sporadically reported among sexual offenders, the evidence is scarce and it might not be specific to this type of offending. The second objective of this investigation was to gather preliminary neuropsychological data with more homogeneous subgroups of sexual offenders. A profile of lower-order executive dysfunctions (e.g. sustained attention and inhibition) and verbal deficits with intact or good capacities for higher-order executive functioning (e.g. reasoning and cognitive flexibility) and visuo-spatial processing was preferentially found among sexual offenders, suggesting basal fronto-temporal anomalies. Importantly, pedophiles were more consistently and severely impaired than rapists of adults. However, this basal fronto-temporal profile is not characteristic of sexual deviance, as it is also found in association with delinquency and criminality in general. Future neuropsychological and brain imaging studies should consider subgroups of sexual offenders and recruit non-sexual violent persons and non-violent individuals in order to disentangle the complex relations between brain anomalies and sexual deviance.