Jonas Kneer

Evidence for superior neurobiological and behavioral inhibitory control abilities in non‐offending as compared to offending pedophiles

Neurobehavioral models of pedophilia and child sexual offending suggest a pattern of temporal and in particular prefrontal disturbances leading to inappropriate behavioral control and subsequently an increased propensity to sexually offend against children. However, clear empirical evidence for such mechanisms is still missing. Using a go/nogo paradigm in combination with functional magnetic resonance imaging (fMRI) we compared behavioral performance and neural response patterns among three groups of men matched for age and IQ: pedophiles with (N = 40) and without (N = 37) a history of hands‐on sexual offences against children as well as healthy non‐offending controls (N = 40). As compared to offending pedophiles, non‐offending pedophiles exhibited superior inhibitory control as reflected by significantly lower rate of commission errors. Group‐by‐condition interaction analysis also revealed inhibition‐related activation in the left posterior cingulate and the left superior frontal cortex that distinguished between offending and non‐offending pedophiles, while no significant differences were found between pedophiles and healthy controls. Both areas showing distinct activation pattern among pedophiles play a critical role in linking neural networks that relate to effective cognitive functioning. Data therefore suggest that heightened inhibition‐related recruitment of these areas as well as decreased amount of commission errors is related to better inhibitory control in pedophiles who successfully avoid committing hands‐on sexual offences against children. Hum Brain Mapp 38:1092–1104, 2017.

Excessive users of violent video games do not show emotional desensitization: an fMRI study.

Playing violent video games have been linked to long-term emotional desensitization. We hypothesized that desensitization effects in excessive users of violent video games should lead to decreased brain activations to highly salient emotional pictures in emotional sensitivity brain regions. Twenty-eight male adult subjects showing excessive long-term use of violent video games and age and education matched control participants were examined in two experiments using standardized emotional pictures of positive, negative and neutral valence. No group differences were revealed even at reduced statistical thresholds which speaks against desensitization of emotion sensitive brain regions as a result of excessive use of violent video games.

Decoding Pedophilia: Increased Anterior Insula Response to Infant Animal Pictures

Previous research found increased brain responses of men with sexual interest in children (i.e., pedophiles) not only to pictures of naked children but also to pictures of child faces. This opens the possibly that pedophilia is linked (in addition to or instead of an aberrant sexual system) to an over-active nurturing system. To test this hypothesis we exposed pedophiles and healthy controls to pictures of infant and adult animals during functional magnetic resonance imaging of the brain. By using pictures of infant animals (instead of human infants), we aimed to elicit nurturing processing without triggering sexual processing. We hypothesized that elevated brain responses to nurturing stimuli will be found – in addition to other brain areas – in the anterior insula of pedophiles because this area was repeatedly found to be activated when adults see pictures of babies. Behavioral ratings confirmed that pictures of infant or adult animals were not perceived as sexually arousing neither by the pedophilic participants nor by the heathy controls. Statistical analysis was applied to the whole brain as well as to the anterior insula as region of interest. Only in pedophiles did infants relative to adult animals increase brain activity in the anterior insula, supplementary motor cortex, and dorsolateral prefrontal areas. Within-group analysis revealed an increased brain response to infant animals in the left anterior insular cortex of the pedophilic participants. Currently, pedophilia is considered the consequence of disturbed sexual or executive brain processing, but details are far from known. The present findings raise the question whether there is also an over-responsive nurturing system in pedophilia.

Executive Functioning in Pedophilia and Child Sexual Offending

OBJECTIVES Pedophilia (P) is a psychiatric disease associated with sexual attraction toward children and often accompanied by child sexual offending (CSO). Consequently, it is important to address the understanding of executive dysfunctions that may increase the probability of CSO. Moreover, this research field has been lacking to disentangle executive deficits associated with pedophilia (as a deviant sexual preference) from those associated with CSO (as a deviant sexual behavior). METHODS The German multi-sided research network NeMUP offers the opportunity to overcome these limitations. By applying the Cambridge Automated Neuropsychological Test Battery in four carefully matched groups of men: (1) pedophiles with (N=45) and (2) without (N=45) a history of sexual offending against children; (3) child molesters without pedophilia (N=19), and (4) non-offending controls (N=49), we were able to analyze executive functioning in pedophilia and CSO independently. RESULTS Both CSO groups as compared to both non-CSO groups exhibited worsened response inhibition ability. However, only non-pedophilic offenders showed additionally disabled strategy use ability. Regarding set-shifting abilities, the P+CSO group showed the best performance. We also found that performances were affected by age: only in pedophiles, response inhibition worsened with age, while age-related deficits in set-shifting abilities were restricted to non-pedophilic participants. The latter also differentiated between both sexual preference groups. CONCLUSIONS Our results are the first to demonstrate that executive dysfunctions are related to offense status rather than pedophilic preference. Furthermore, there was evidence for differentiating age and performance correlations between pedophiles and non-pedophiles, which warrants further investigation. (JINS, 2017, 23, 460-470).

Approach and Avoidance Tendencies Toward Picture Stimuli of (Pre-)Pubescent Children and Adults: An Investigation in Pedophilic and Nonpedophilic Samples:

The presence of pedophilic sexual interests is considered of high importance for predicting recidivism among individuals who have committed sexual offenses. However, objective and valid assessment methods that are robust against confounding issues such as cognitive capacity and manipulation are sparse. We applied the Approach–Avoidance Task (AAT) for detecting sexual interests in 38 pedophilic men (18 primarily attracted to boys) and 27 male nonpedophilic (11 gay) participants. The AAT relies on automatic approach and avoidance tendencies, independent of cognitive abilities such as memory capacity and intelligence. Approach–avoidance tendencies toward stimuli depicting seminude prepubescent boys and girls as well as men and women are reported. The results were consistent with previous research on the utility of the AAT: Except for pedophiles attracted to girls, the mean AAT scores (approach minus avoidance reaction time for each stimulus category) were positive only for stimuli of the preferred category. A multivariate binary logistic regression approach revealed 80% overall accuracy in differentiating pedophilic from nonpedophilic participants.

Diminished fronto-limbic functional connectivity in child sexual offenders

BACKGROUND Child sexual abuse and neglect have been related to an increased risk for the development of a wide range of behavioral, psychological, and sexual problems and increased rates of suicidal behavior. Contrary to the large amount of research focusing on the negative mental health consequences of child sexual abuse, very little is known about the characteristics of child sexual offenders and the neuronal underpinnings contributing to child sexual offending. METHODS AND SAMPLE This study investigates differences in resting state functional connectivity (rs-FC) between non-pedophilic child sexual offenders (N = 20; CSO-P) and matched healthy controls (N = 20; HC) using a seed-based approach. The focus of this investigation of rs-FC in CSO-P was put on prefrontal and limbic regions highly relevant for emotional and behavioral processing. RESULTS Results revealed a significant reduction of rs-FC between the right centromedial amygdala and the left dorsolateral prefrontal cortex in child sexual offenders compared to controls. CONCLUSION & RECOMMENDATIONS Given that, in the healthy brain, there is a strong top-down inhibitory control of prefrontal over limbic structures, these results suggest that diminished rs-FC between the amygdala and the dorsolateral prefrontal cortex and may foster sexual deviance and sexual offending. A profound understanding of these concepts should contribute to a better understanding of the occurrence of child sexual offending, as well as further development of more differentiated and effective interventions.

Clinical characteristics associated with paedophilia and child sex offending – Differentiating sexual preference from offence status

Contrary to public perception, child sex offending (CSO) and paedophilia are not the same. Only half of all cases of CSO are motivated by paedophilic preference, and a paedophilic preference does not necessarily lead to CSO. However, studies that investigated clinical factors accompanying and contributing to paedophilia so far mainly relied on paedophiles with a history of CSO. The aim of this study was to distinguish between factors associated with sexual preference (paedophile versus non-paedophile) and offender status (with versus without CSO). Accordingly, a 2 (sexual preference) × 2 (offender status) factorial design was used for a comprehensive clinical assessment of paedophiles with and without a history of CSO (n = 83, n = 79 respectively), child sex offenders without paedophilia (n = 32) and healthy controls (n = 148). Results indicated that psychiatric comorbidities, sexual dysfunctions and adverse childhood experiences were more common among paedophiles and child sex offenders than controls. Offenders and non-offenders differed in age, intelligence, educational level and experience of childhood sexual abuse, whereas paedophiles and non-paedophiles mainly differed in sexual characteristics (e.g., additional paraphilias, onset and current level of sexual activity). Regression analyses were more powerful in segregating offender status than sexual preference (mean classification accuracy: 76% versus 68%). In differentiating between offence- and preference-related factors this study improves clinical understanding of both phenomena and may be used to develop scientifically grounded CSO prevention and treatment programmes. It also highlights that some deviations are not traceable to just one of these two factors, thus raising the issue of the mechanism underlying both phenomena.

Multimodal neuroimaging measures and intelligence influence pedophile child sexual offense behavior

Pedophilia is a heterogeneous disorder for which the neurobiological correlates are not well established. In particular, there are no biological markers identifying individuals with high risk to commit child sexual offense (CSO). Pedophiles with CSO (P+CSO; N = 73), pedophiles without CSO (P-CSO; N = 77), and non-pedophilic controls (NPC; N = 133) were assessed using multimodal structural neuroimaging measures including: cortical thickness (CT), surface area (SA), and white matter fractional anisotropy (FA), as well as full scale IQ (FSIQ) performance. Cortex-wise mediation analyses were used to assess the relationships among brain structure, FSIQ and CSO behavior. Lower FSIQ performance was strongly predict with P+CSO (Wald Chi2 = 13.0, p = 3.1 × 10-5). P+CSO had lower CT in the right motor cortex and pronounced reductions in SA spanning the bilateral frontal, temporal, cingulate, and insular regions (PFWE-corrected < 0.05). P+CSO also had lower FA particularly in the corpus callosum (PFWE-corrected < 0.05). The relationship between SA and P+CSO was significantly mediated by FSIQ, particularly in the prefrontal and anterior insular cortices (PFWE-corrected < 0.05). Within P+CSO, left prefrontal and right anterior cingulate SA negatively correlated with number of CSOs (PFWE-corrected < 0.05). This study demonstrates converging neurobiological findings in which P+CSO had lower FSIQ performance, reduced CT, reduced SA, and reduced FA, compared to P-CSO as well as NPC. Further, FSIQ potentially mediates abuse by pedophiles via aberrant SA, whereas the CT and FA associations were independent of FSIQ differences. These findings suggest aberrant neuroanatomy and lower intelligence as a potential core feature underlying child sexual abuse behavior by pedophiles.

Interaction between behavioral inhibition and emotional processing in borderline personality disorder using a pictorial emotional go/no-go paradigm

Borderline personality disorder (BPD) is characterized by difficulties in emotional regulation and impulse control. In this study, we presented a novel picture-based emotional go/no-go task with distracting emotional faces in the background, which was administered to 16 patients with BPD and 16 age-matched healthy controls. The faces displayed different emotional content (angry, neutral, or happy). Results showed differences in sensitivity between patients and the control group, with patients exhibiting less sensitivity in the task, and also showed influences of emotional content represented in the distracting faces in both groups. Specifically, happy faces decreased sensitivity compared to angry faces. It seemed as though processing of a positive emotional stimulus led to a more relaxed state and thereby to decreased sensitivity, while a negative emotional stimulus induced more alertness and tension, leading to higher sensitivity. Thus, this paradigm is suitable to investigate the interplay between emotion processing and impulse control in patients with BPD.