Neuropsychological deficits in sexual offenders: Implications for treatment

Neuroelectric Correlates of Human Sexuality: A Review and Meta-Analysis

Many reviews on sexual arousal in humans focus on different brain imaging methods and behavioral observations. Although neurotransmission in the brain is mainly performed through electrochemical signals, there are no systematic reviews of the electrophysiological correlates of sexual arousal. We performed a systematic search on this subject and reviewed 255 studies including various electrophysiological methods. Our results show how neuroelectric signals have been used to investigate genital somatotopy as well as basic genital physiology during sexual arousal and how cortical electric signals have been recorded during orgasm. Moreover, experiments on the interactions of cognition and sexual arousal in healthy subjects and in individuals with abnormal sexual preferences were analyzed as well as case studies on sexual disturbances associated with diseases of the nervous system. In addition, 25 studies focusing on brain potentials during the interaction of cognition and sexual arousal were eligible for meta-analysis. The results showed significant effect sizes for specific brain potentials during sexual stimulation (P3: Cohen's d = 1.82, N = 300, LPP: Cohen's d = 2.30, N = 510) with high heterogeneity between the combined studies. Taken together, our review shows how neuroelectric methods can consistently differentiate sexual arousal from other emotional states.

The neuropsychology of sex offenders: a meta-analysis

Typically, neuropsychological studies of sex offenders have grouped together different types of individuals and different types of measures. This is why results have tended to be nonspecific and divergent across studies. Against this background, the authors undertook a review of the literature regarding the neuropsychology of sex offenders, taking into account subgroups based on criminological theories. They also conducted a meta-analysis of the data to demonstrate the cognitive heterogeneity of sex offenders statistically. Their main objective was to test the hypothesis to the effect that the neuropsychological deficits of sex offenders are not broad and generalized compared with specific subgroups of participants based on specific measures. In all, 23 neuropsychological studies reporting data on 1,756 participants were taken into consideration. As expected, a highly significant, broad, and heterogeneous overall effect size was found. Taking subgroups of participants and specific cognitive measures into account significantly improved homogeneity. Sex offenders against children tended to obtain lower scores than did sex offenders against adults on higher order executive functions, whereas sex offenders against adults tended to obtain results similar to those of non-sex offenders, with lower scores in verbal fluency and inhibition. However, it is concluded that neuropsychological data on sex offenders are still too scarce to confirm these trends or to test more precise hypotheses. For greater clinical relevance, future neuropsychological studies should consider specific subgroups of participants and measures to verify the presence of different cognitive profiles.

Executive function profiles of pedophilic and nonpedophilic child molesters

There is increasing evidence of neurocognitive dysfunction among child molesters, supporting the notion of brain anomalies among pedophiles. However, approximately half of child molesters are not pedophilic (i.e., are not primarily attracted to children), and neurocognitive differences between pedophilic (PED) and nonpedophilic (NPED) child molesters are not well understood. The purpose of this study was to assess neurocognition, specifically executive functioning (EF), among phallometrically defined PED and NPED child molesters, relative to nonsexual offenders (NSO). Participants (N = 89) were compared on seven EF domains. Results revealed that (a) child molesters exhibited an overall executive profile that was different from that of NSOs, with PEDs differing from NSOs but not from NPEDs; (b) child molesters on the whole performed better than NSOs on abstract reasoning and more poorly on inhibition; and (c) PEDs performed better than NPEDs on planning and exhibited better overall performance accuracy relative to NPEDs. These results suggest that PEDs exhibit a more deliberate, planful response style characterized by greater self-monitoring; whereas NPEDs appear to respond more impulsively. The current report further elucidates neurocognition among child molesters and highlights the need for future research examining subtypes of child molesters.

Neurocognitive differences between pedophilic and nonpedophilic child molesters

Although some evidence exists that child molesters may be characterized by structural and functional brain abnormalities, findings across studies are inconsistent. Past cognitive research in this area has been extensively criticized for relying on conceptually weak batteries, measures of questionable reliability, and poorly defined samples (i.e., failing to distinguish between pedophilic and nonpedophilic child molesters). The present study aimed to address the weaknesses of past research by comparing 40 child molesters (20 pedophilic and 20 nonpedophilic) and 20 demographically matched nonoffender controls on six well-defined neurocognitive composite scores of comparable reliability (i.e., semantic knowledge, executive functioning, processing speed, motor speed, auditory memory, and visual memory). Results indicated that pedophilic child molesters exhibit slower processing speed, nonpedophilic child molesters exhibit poorer semantic knowledge, and both molester groups exhibit executive weaknesses as compared to nonoffender controls. This study is the first to compare the two molester types on neurocognitive functions. The observed differences between the molester groups help explain inconsistencies in past research and demonstrate the need to distinguish between the two types of child molesters when studying neurobiologic underpinnings of sexual offending.

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.

Treating sexual dysfunction in sex offenders: a case example

Sex offender treatment as a specialized procedure is maturing, and more comprehensive approaches that treat co-morbid patient problems (e.g., mood and anxiety disorders, relationship conflicts, social skills deficits) have emerged. However, little attention has been given to the role of sexual dysfunction in the assessment and treatment of sex offenders. We propose that: (a) sexual dysfunction is a prevalent co-occurring sexual disorder in sex offenders; (b) sexual dysfunction is, by definition, a lack of sexual health, which diminishes overall life satisfaction; and (c) sexual dysfunction can be a contributing factor for some in maintaining offense-related arousal patterns and therefore is a potential contributor to sex-offense risk. This article describes the importance of treating sex dysfunction in selected cases when it is present among men in sex offender treatment, in order to improve the men's quality of life and to deter sex offense recidivism. A brief case example illustrates this benefit.

Psychological assessment, treatment, and outcome with sex offenders

The frequency and impact of sexual offenses have led to the recent enactment of sexual "predator" laws. Such laws are intended to reduce sexual violence through treatment and involuntary confinement. Sixty years ago, similar laws identifying "sexual psychopaths" were enacted and, in many states, eventually repealed for multiple reasons; among those reasons was an inability to demonstrate that treatment had any significant impact on recidivism. That inability forced us to reexamine, among other issues, the population(s) which undergo treatment, the outcomes that are used to measure treatment effectiveness, and the processes that constitute treatment itself. Those issues are considered in this paper through a review of treatment programs based on psychodynamic, behavioral, and cognitive-behavioral theories. Although the evidence is sparse, it is fair to conclude that the latter have been found to be effective. We call for dynamic measures, effective treatments, and the resources necessary for both developments.