Sexual offenses and the brain

Sexual offenses are a great concern worldwide due to the devastating physical and psychological consequences the victims of such crimes often experience. It is an important task to investigate potential mechanisms that may underlie sexual offending and predispose an individual for such antisocial behavior. Advanced techniques in neuroscience are increasingly used to uncover biomarkers in psychiatric disorders and organic brain disease. As this type of research is flourishing, preliminary studies with the aim to explore the neural basis of sex offenders have started to appear. To this purpose, researchers began to study the brain's structural and functional changes and the neurocognitive profiles of sex offenders, in comparison to nonoffenders and nonsex offenders, or among different subtypes of sex offenders. Most of the research to date has focused on pedophilia, with some inconsistent findings, which hampers the translation of the results into the forensic and clinical context. Any attempt to increase convergent evidence may profit from the harmonization of data analysis and avoidance of methodological inconsistencies, which can account for the different results across studies. Today, uncovering the neural basis of sex offences has to become a priority, not only for clinical interventions, but might also be important knowledge for crime prevention.

Abnormal behavioral and neural responses in the right dorsolateral prefrontal cortex during emotional interference for cognitive control in pedophilic sex offenders

Studies within the last decade have reported neural and behavioral differences in cognitive control between men with the pedophilic disorder who commit (CSO+) and do not commit (CSO-) child sexual abuse. Prior studies reported a higher number of errors in Go/Nogo task and lower activity of the prefrontal cortex in NoGo trials, in CSO+ compared with CSO-. Moreover, negative mood was reported as a risk factor for child sexual abuse in pedophilic men. We aimed to examine differences in brain function and behavior between CSO+ and CSO- patients regarding emotional interference on cognitive processes and inhibition. We recruited CSO+ (n = 11) and CSO- (n = 14) patients as well as matched healthy controls (HC) (n = 17). Participants performed the affective Go/NoGo task in a block-design functional magnetic resonance imaging experiment. The task comprised the following four conditions: Negative Go, including only Go stimuli and negatively valenced pictures; Negative NoGo, including 50% of Go and 50% of NoGo trials as well as negatively valenced pictures; and two corresponding conditions with neutral pictures. Brain analysis was restricted to the dorsolateral prefrontal (DLPFC), orbitofrontal, and anterior cingulate cortices. The HC and CSO- groups, but not the CSO+ group, showed significantly slower reactions in negative blocks compared with neutral blocks. Brain analysis revealed increased activation in the right DLPFC during emotional interference contrast (Negative > Neutral) in the HC and CSO- groups; however, there was decreased activation in the CSO+ group. In the CSO+ group, negative distractors did not increase cognitive control processes, which was observed in the CSO- and HC groups at the behavioral and neural levels. These results support previous reports indicating offender status is associated with cognitive and emotional impairments.

Are There Any Biomarkers for Pedophilia and Sexual Child Abuse? A Review

The use of biomarkers in medicine is a common and valuable approach in several clinical fields. Understanding the relationship between measurable biological processes and clinical outcomes not only is indispensable in the face of understanding physiological processes in healthy as well as in diseased organisms but also for understanding and evaluating treatment effects. Therefore, also in the context of forensic psychiatry, biomarkers and their potentially beneficial effects are of growing interest. The objective of this review is to examine if there are biomarkers that may serve as a tool to support diagnostic process, treatment evaluation, and risk assessment of pedophilic individuals and child sexual offenders. In the first part, we present an overview of the current neurobiological, as well as physiological and psychophysiological approaches to characterize pedophilia and child sexual offending. Secondly, we discuss and evaluate the impact of these approaches on the development of biomarkers for diagnosis, therapy, and risk assessment in pedophilic subjects and child sexual offenders. We conclude that a lot of research has already enhanced our neurobiological knowledge about pedophilia and child sexual offending. Although there surely exist promising parameters and approaches, in our view currently none of these is ready yet to serve as a clinically applicable diagnostic, response, or predictive biomarker for pedophilia and child sexual offending. Therefore, further work remains to be done. The development of a composite diagnostic biomarker to assess deviant sexual interest, combining several measures like functional magnetic resonance imaging, electroencephalogram, eye tracking, and behavioral approaches seems to be most promising. A valid and reliable measurement of deviant sexual interest, insensitive to manipulations could significantly support clinical diagnostic process. Similarly, regarding therapy evaluation and risk assessment, a composite biomarker to assess inhibitory control functions seems to be promising. Furthermore, the application of the Research Domain Criteria-approach, a new approach for investigating and classifying mental disorders, offers the possibility to take research to a new level.

A paedophile scan to prevent child sexual abuse in child care? A thought experiment to problematize the notion of alignment in Responsible Research and Innovation

Responsible Research and Innovation (RRI) is a science policy concept that gained traction from 2000 onwards in the EU and US, in which alignment on purposes and values between different stakeholders is a key aspect. This thought experiment problematizes this particular notion: ethically acceptable and societally desirable outcomes are not necessarily achieved when alignment is a consequence of early closure. To argue this point, we took the example of the potential development of scanning technology for the detection of paedophilia among job applicants, for which indicators of broad societal support were found in an RRI project on neuroimaging. We analysed this case by looking through several lenses, obtained by structured and non-structured literature searches. We explored how facts and values are masked when a taboo topic is considered. This results in the black boxing of the problem definition, potential solutions and development trajectories. Complex unstructured problems can thus be perceived as manageable structured problems, which can in turn lead to irresponsible policies surrounding technology development. Responsible processes of research and technology development thus require the involvement of a critical reflector who is alert to signs of early closure and who prevents foreclosure of ongoing reflexive deliberation. There is an important role for ethical, legal and societal aspect studies within the framework of RRI. This paper shows that the concepts of "value/fact diversity masking" and "early discursive closure" are new avenues for RRI research.

Correlates of emotional congruence with children in sexual offenders against children: a test of theoretical models in an incarcerated sample

Emotional congruence with children is a psychological construct theoretically involved in the etiology and maintenance of sexual offending against children. Research conducted to date has not examined the relationship between emotional congruence with children and other psychological meaningful risk factors for sexual offending against children. The current study derived potential correlates of emotional congruence with children from the published literature and proposed three models of emotional congruence with children that contain relatively unique sets of correlates: the blockage, sexual deviance, and psychological immaturity models. Using Area under the Curve analysis, we assessed the relationship between emotional congruence with children and offense characteristics, victim demographics, and psychologically meaningful risk factors in a sample of incarcerated sexual offenders against children (n=221). The sexual deviance model received the most support: emotional congruence with children was significantly associated with deviant sexual interests, sexual self-regulation problems, and cognition that condones and supports child molestation. The blockage model received partial support, and the immaturity model received the least support. Based on the results, we propose a set of further predictions regarding the relationships between emotional congruence with children and other psychologically meaningful risk factors to be examined in future research.

Perceived parental attachment, personality characteristics, and cognition in male incest

The aim of this study was to investigate the multiple pathways of perceived child-rearing practices, cognitive-executive functions, and personality characteristics in incest and other sexual offenders. The participants consisted of 217 male sexual offenders who were in custody in southern Taiwan. Participants were divided into two groups of 25 incest and 192 nonincest sexual offenders. The incest offenders tended to be less extraverted and worse in abstract reasoning ability, and to have more perseverative thinking, and perceived less parental care than other sexual offenders. Moreover, the structural equation model showed that the effect of parental care on the type of sexual offense is mediated by cognitive-executive functions and personality traits. This finding suggests that the personality traits, cognitive function, and parental attachment of incest offenders differ from other sexual offenders. This result can be a helpful reference in sexual-offender intervention programs for relapse prevention.

Sexual offenders in prison psychiatric treatment: a biopsychosocial description

In this study, 120 males (60 sexual offenders and 60 non-sexual offenders) in psychiatric treatment while in prison were evaluated using neuropsychological, psychological, and sociological/demographic measures. All sexual offenders (N = 60) would be evaluated for potential civil commitment as sexually violent predators before prison release. Non-sexual offenders (N = 60) had not been convicted of a sexual offense. Sexual offenders demonstrated significantly more overall neuropsychological impairment suggesting diffuse brain differences, with dysfunction primarily associated with temporal and frontal brain cortexes; higher Psychopathy Checklist-Revised Factor 1 (Interpersonal/Affective) ratings and Rorschach responses indicated disordered attachment, disordered self-perception, and impulsive emotionality. Sexual offenders also were more likely to be younger and unmarried. Stepwise logistic regression analysis resulted in 80.20% accuracy of prediction of sexual offenders. Potential application of this empirically derived multidimensional description to treatment of sexual offenders is discussed. Potential limitations to generalization of this information are also discussed.

Etiology of pedophilia from a neurodevelopmental perspective: markers and brain alterations

DEVELOPMENT

Distinct signs have been associated with a wide range of neurodevelopmental disorders and warning signs of neural developmental problems have also been observed in pedophiles. Continuing this line of research, several neuroimaging studies have found neural alterations in this disorder.

CONCLUSIONS

Pedophilia has been related to distinct indicators of neurodevelopmental alterations such as low intelligence quotient, left-handedness and smaller stature, among others. In addition, pedophiles show several neural alterations and a predominantly subcortical pattern of cerebral activation to sexual stimuli. The results of these studies suggest that the origin of pedophilia may partly lie in brain alterations due to problems during neural development, although these alterations do not absolve these persons of responsibility for their actions.

Cerebral white matter deficiencies in pedophilic men

The present investigation sought to identify which brain regions distinguish pedophilic from nonpedophilic men, using unbiased, automated analyses of the whole brain. T1-weighted magnetic resonance images (MRIs) were acquired from men who demonstrated illegal or clinically significant sexual behaviors or interests (n = 65) and from men who had histories of nonsexual offenses but no sexual offenses (n = 62). Sexual interest in children was assessed by participants' admissions of pedophilic interest, histories of committing sexual offenses against children, and psychophysiological responses in the laboratory to erotic stimuli depicting children or adults. Automated parcellation of the MRIs revealed significant negative associations between pedophilia and white matter volumes of the temporal and parietal lobes bilaterally. Voxel-based morphometry corroborated the associations and indicated that the regions of lower white matter volumes followed, and were limited to, two major fiber bundles: the superior fronto-occipital fasciculus and the right arcuate fasciculus. No significant differences were found in grey matter or in cerebrospinal fluid (CSF). Because the superior fronto-occipital and arcuate fasciculi connect the cortical regions that respond to sexual cues, these results suggest (1) that those cortical regions operate as a network for recognizing sexually relevant stimuli and (2) that pedophilia results from a partial disconnection within that network.

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.

Social, neuroradiologic, medical, and neuropsychologic correlates of sexually aberrant behavior after traumatic brain injury: a controlled study

OBJECTIVE

To identify social, neuroradiological, medical, and neuropsychological correlates of sexually aberrant behavior (SAB) after traumatic brain injury (TBI).

DESIGN

A controlled study using a retrospective file review.

SETTING

A brain injury unit providing inpatient and outpatient rehabilitation services.

PARTICIPANTS

A sample of males (n = 25) exhibiting SABs and a control group (n = 25) matched for gender, severity of injury, age at injury, and time after injury.

MAIN OUTCOME MEASURES

A protocol that recorded data on demographic, injury, radiological, medical, and neuropsychological variables.

RESULTS

The SAB group had a significantly higher incidence of postinjury psychosocial disturbance in areas of nonsexual crime and failure to return to work than the matched TBI group. There were no significant differences between the two groups in the incidence of premorbid psychosocial disturbance or postinjury radiological, medical, or neuropsychological variables.

CONCLUSIONS

The study results caution against simplistic explanations of SAB as the product of damage to the frontal-lobe systems or premorbid psychosocial disturbance. Furthermore, the results suggest that a wide-ranging assessment of people with TBI who exhibit SABs is required, because results of neuropsychological examination alone cannot be considered conclusive. Future research into the etiology of SABs could examine additional factors such as lack of insight, lack of empathy, and premorbid history of family dysfunction.

Traumatic brain injury in individuals convicted of sexual offenses with and without bipolar disorder

The authors examined the occurrence of traumatic brain injury (TBI) in individuals convicted of sexual offenses with and without bipolar disorder and a comparison group of patients with bipolar disorder without a history of sexual offending behaviors. Individuals convicted of sexual offenses and diagnosed with bipolar disorder had greater rates of brain injury resulting from head trauma than individuals convicted of sexual offenses without bipolar disorder and comparison patients with bipolar disorder. TBI predated the first sexual offense and/or the onset of bipolar disorder in most subjects.

Sex offending as a psychosocial sequela of traumatic brain injury

OBJECTIVE

To describe the nature and extent of sexual offending after traumatic brain injury (TBI).

DESIGN

Retrospective file review.

SETTING

A brain injury unit providing inpatient and outpatient rehabilitation services.

PARTICIPANTS

A review of five years of admissions to the Brain Injury Rehabilitation Unit (N = 477) identified a sample of 29 males who committed 128 incidents of sex offending.

MAIN OUTCOME MEASURES

A protocol to record data on demographic, injury, radiological, and psychosocial variables and offending behaviors.

RESULTS

Of the total population of 445 clients with TBI, 6.5% (n = 29) were identified as having committed some form of sexual offense. Alcohol was a factor in only three (2.3%) of the incidents, and only two clients had a preinjury history of sexual offending. The most common offenses were the "touching" offenses, followed by exhibitionism and overt sexual aggression. Staff members were the most common targets of the offenses, followed by members of the general public, other people with TBI, and family members.

CONCLUSIONS

Sex offending is a significant clinical problem among a small minority of men after TBI. The absence of alcohol and preinjury histories of sexual offending suggest that the brain injury and contingent sequelae were a significant etiological factor underlying the offenses. A number of implications for the clinical management of clients with sexually aberrant behaviors is identified and discussed.

Medroxyprogesterone in the treatment of aggressive hypersexual behavior in traumatic brain injury

Sexual function is among the many areas affected by traumatic brain injury. The most common change is decreased sexual performance and satisfaction, for the brain injured person and the sexual partner. Hypersexuality, especially inappropriate sexual comments and gestures, is also a common result of traumatic brain injury. A case of hypersexuality in a severely disabled brain injured man is presented. He was successfully treated with medroxyprogesterone acetate after failure of multiple other treatment strategies. The literature is reviewed. An evaluation and treatment strategy for sexual dysfunction post traumatic brain injury is presented.

Selective reductions in prefrontal glucose metabolism in murderers

This study tests the hypothesis that seriously violent offenders pleading not guilty by reason of insanity or incompetent to stand trial are characterized by prefrontal dysfunction. This hypothesis was tested in a group of 22 subjects accused of murder and 22 age-matched and gender-matched controls by measuring local cerebral uptake of glucose using positron emission tomography during the continuous performance task. Murderers had significantly lower glucose metabolism in both lateral and medial prefrontal cortex relative to controls. No group differences were observed for posterior frontal, temporal, and parietal glucose metabolism, indicating regional specificity for the prefrontal deficit. Group differences were not found to be a function of raised levels of left-handedness, schizophrenia, ethnic minority status, head injury, or motivation deficits in the murder group. These preliminary results suggest that deficits localized to the prefrontal cortex may be related to violence in a selected group of offenders, although further studies are needed to establish the generalizability of these findings to violent offenders in the community.