Boris Schiffer

Functional brain correlates of heterosexual paedophilia.

Although the neuronal mechanisms underlying normal sexual motivation and function have recently been examined, the alterations in brain function in deviant sexual behaviours such as paedophilia are largely unknown. The objective of this study was to identify paedophilia-specific functional networks implicated in sexual arousal. Therefore a consecutive sample of eight paedophile forensic inpatients, exclusively attracted to females, and 12 healthy age-matched heterosexual control participants from a comparable socioeconomic stratum participated in a visual sexual stimulation procedure during functional magnetic resonance imaging. The visual stimuli were sexually stimulating photographs and emotionally neutral photographs. Immediately after the imaging session subjective responses pertaining to sexual desire were recorded. Principally, the brain response of heterosexual paedophiles to heteropaedophilic stimuli was comparable to that of heterosexual males to heterosexual stimuli, including different limbic structures (amygdala, cingulate gyrus, and hippocampus), the substantia nigra, caudate nucleus, as well as the anterior cingulate cortex, different thalamic nuclei, and associative cortices. However, responses to visual sexual stimulation were found in the orbitofrontal cortex in healthy heterosexual males, but not in paedophiles, in whom abnormal activity in the dorsolateral prefrontal cortex was observed. Thus, in line with clinical observations and neuropsychological studies, it seems that central processing of sexual stimuli in heterosexual paedophiles may be altered by a disturbance in the prefrontal networks, which, as has already been hypothesized, may be associated with stimulus-controlled behaviours, such as sexual compulsive behaviours. Moreover, these findings may suggest a dysfunction (in the functional and effective connectivity) at the cognitive stage of sexual arousal processing.

Disentangling Structural Brain Alterations Associated With Violent Behavior From Those Associated With Substance Use Disorders

CONTEXT Studies aimed at identifying structural brain alterations associated with persistent violent behavior or psychopathy have not adequately accounted for a lifetime history of substance misuse. Thus, alterations in gray matter (GM) volume that have been reported to be correlates of violent behavior and/or psychopathy may instead be related to lifelong substance use disorders (SUDs). OBJECTIVE To identify alterations in GM volume associated with violent behavior and those associated with lifelong SUDs. DESIGN Cross-sectional study. SETTING Participants were recruited from penitentiaries, forensic hospitals, psychiatric outpatient services, and communities in Germany. Structural magnetic resonance imaging was performed at a university hospital. PARTICIPANTS Four groups of men were compared: 12 men with SUDs who exhibited violent behavior (hereafter referred to as violent offenders), 12 violent offenders without SUDs, 13 men with SUDs who did not exhibit violent behavior (hereafter referred to as nonoffenders), and 14 nonoffenders without SUDs. MAIN OUTCOME MEASURES Voxel-based morphometry was used to analyze high-resolution magnetic resonance imaging scans. Assessments of mental disorders, psychopathy (using the Psychopathy Checklist-Screening Version), aggressive behavior, and impulsivity were conducted by trained clinicians. RESULTS Compared with nonoffenders, violent offenders presented with a larger GM volume in the amygdala bilaterally, the left nucleus accumbens, and the right caudate head and with less GM volume in the left insula. Men with SUDs exhibited a smaller GM volume in the orbitofrontal cortex, ventromedial prefrontal cortex, and premotor cortex than did men without SUDs. Regression analyses indicated that the alterations in GM volume that distinguished the violent offenders from nonoffenders were associated with psychopathy scores and scores for lifelong aggressive behavior. The GM volumes of the orbitofrontal cortex and prefrontal cortex that distinguished the men with SUDs from the men without SUDs were correlated with scores for response inhibition. CONCLUSIONS These findings suggest that a greater GM volume in the mesolimbic reward system may be associated with violent behavior and that reduced GM volumes in the prefrontal cortex, orbitofrontal cortex, and premotor area characterize men with SUDs.

Brain Response to Visual Sexual Stimuli in Heterosexual and Homosexual Males

Although heterosexual and homosexual individuals clearly show differences in subjective response to heterosexual and homosexual sexual stimuli, the neurobiological processes underlying sexual orientation are largely unknown. We addressed the question whether the expected differences in subjective response to visual heterosexual and homosexual stimuli may be reflected in differences in brain activation pattern. Twenty‐four healthy male volunteers, 12 heterosexuals and 12 homosexuals, were included in the study. BOLD signal was measured while subjects were viewing erotic videos of heterosexual and homosexual content. SPM02 was used for data analysis. Individual sexual arousal was assessed by subjective rating. As compared to viewing sexually neutral videos, viewing erotic videos led to a brain activation pattern characteristic for sexual arousal in both groups only when subjects were viewing videos of their respective sexual orientation. Particularly, activation in the hypothalamus, a key brain area in sexual function, was correlated with sexual arousal. Conversely, when viewing videos opposite to their sexual orientation both groups showed absent hypothalamic activation. Moreover, the activation pattern found in both groups suggests that stimuli of opposite sexual orientation triggered intense autonomic response and may be perceived, at least to some extent, as aversive. Hum Brain Mapp, 2008.

Executive Dysfunctions in Pedophilic and Nonpedophilic Child Molesters

INTRODUCTION There is some evidence that child molesters show neuropsychological abnormalities which might reflect specific structural and/or functional brain alterations, but there are also inconsistencies in the existing findings which need to be clarified. Most of the different outcomes can either be explained by the fact that different types of child molesters were examined or by not having accounted for basically confounding factors such as age, education/intelligence, or criminality. AIM The present study therefore sought to determine whether pedophilic and nonpedophilic child molesters, compared to relevant control groups, show different profiles of executive dysfunction when accounting for potentially confounding factors. METHODS The performance of 30 child molesters (15 pedophilic and 15 nonpedophilic) and 33 age- and education-matched controls (16 nonsexual offenders and 17 healthy controls) was assessed regarding several neuropsychological functions. MAIN OUTCOME MEASURES Scores on different neurocognitive tests and semistructured diagnostical interviews. RESULTS Results indicate that pedophilic child molesters exhibited less performance deficits in cognitive functioning than nonpedophilic child molesters. Compared to healthy controls and nonsexual offenders, the pedophilic child molesters only showed executive dysfunction concerning response inhibition, whereas the nonpedophilic child molesters revealed more severe dysfunction, especially on tasks associated with cognitive flexibility and verbal memory. CONCLUSIONS These results enhance our knowledge about executive dysfunction associated with criminality and/or pedophilia, as they suggest different profiles of impairment between groups. In summary, data suggest that nonpedophilic child molesters showed more severe cognitive deficits than pedophilic child molesters. However, as response inhibition is associated with prefrontal (i.e., orbitofrontal) functioning, the deficits observed in both child molester groups indicate dysfunction in the orbitofrontal cortex. This has to be further examined with functional imaging approaches in larger samples and a full-factorial approach which allows for a clear distinction between criminality and pedophilia in a factorial manner.

Impulsivity-related brain volume deficits in schizophrenia-addiction comorbidity

Despite a high prevalence of schizophrenia patients with comorbid substance abuse, little is known about possible impacts on the brain. Hence, our goal was to determine whether addicted and non-addicted schizophrenic patients suffer from different brain deficits. We were especially interested to determine if grey matter volumes were affected by impulsivity. We hypothesized that (comorbid) substance abuse would be associated with enhanced impulsivity and that this enhanced impulsivity would be related to grey matter volume deficits in prefrontal areas. We employed a voxel-based morphometry approach as well as neuropsychological assessment of executive functions and trait impulsivity in 51 participants (age range 23-55). The schizophrenia group comprised 24 patients (12 patients with paranoid schizophrenia and 12 with additional comorbid substance use disorders). The comparison group comprised 27 non-schizophrenic individuals, matched by age and education (14 healthy individuals and 13 patients with substance use disorders). Total grey matter volume deficits were found in all patient groups as compared with healthy controls but were largest (~8%) in both addicted groups. While grey matter volume losses in lateral orbitofrontal and temporal regions were affected by schizophrenia, volume decreases of the medial orbitofrontal, anterior cingulate and frontopolar cortex were associated with addiction. Compared with non-addicted schizophrenics, comorbid patients showed significant volume decreases in anterior cingulate, frontopolar and superior parietal regions. Additionally, they showed an increased non-planning impulsivity that was negatively related to grey matter volumes in the same regions, except for parietal ones. The present study indicates severe grey matter volume and functional executive deficits in schizophrenia, which were only partially exacerbated by comorbid addiction. However, the relationship between non-planning impulsivity and anterior cingulate and frontopolar grey matter volumes points to a specific structure-function relationship that seems to be impaired in schizophrenia-addiction comorbidity.

Serial neurochemical measurement of cerebrospinal fluid during the human sexual response cycle

Recent studies examining the neuroendocrine response pattern underlying the human sexual response cycle revealed transient activation of the sympathoadrenal system and a substantial, long‐lasting increase in plasma prolactin concentrations following orgasm in men and women. Prolactin has been discussed as being part of a feedback mechanism that signals centers in the central nervous system, such as the dopaminergic system controlling sexual arousal. To further elucidate the central role of neuropeptides, biogenic monoamines and neurotransmitters in human sexual behavior, a serial cerebrospinal fluid (CSF)‐sampling technique was implemented using a previously established experimental paradigm for sexual activity in a laboratory setting. In parallel with peripheral endocrine measures, lumbar CSF was drawn via an indwelling spinal catheter during the sexual response cycle in 10 healthy males and 10 age‐matched controls, and analysed for prolactin, oxytocin, biogenic monoamines and/or their metabolites as well as inhibitory and excitatory neurotransmitter concentrations. Parallel to raised peripheral sympathetic activity, norepinephrine also increased in CSF during audiovisual, masturbation‐induced sexual arousal and orgasm, and remained elevated for the remainder of the session (F4,72 = 8.79, P = 0.000). In contrast, none of the other measures, in particular prolactin and dopamine or its metabolites, reflected significant alteration. In conclusion, the human sexual response cycle is characterized by an increase in sympathetic activity in plasma and CSF, and by pronounced secretion of plasma prolactin after orgasm. However, alterations in dopaminergic or peptidergic activity are not found in lumbar CSF, possibly due to local and restricted release in diencephalic and mesencephalic brain regions.

Brain alterations in paedophilia: A critical review

Psychosocial and biological factors have been implicated in paedophilia, such as alterations in brain structure and function. The purpose of this paper is to review the expanding body of literature on this topic including brain abnormality case reports, as well as structural and functional neuroimaging studies. Case studies of men who have committed sexual offences against children implicate frontal and temporal abnormalities that may be associated with impaired impulse inhibition. Structural neuroimaging investigations show volume reductions in paedophilic men. Although the findings have been heterogeneous, smaller amygdala volume has been replicated repeatedly. Functional neuroimaging investigations demonstrate an overlap between paedophiles and teleiophiles during sexual arousal processing. While it is controversial among studies regarding group differences, reliable discrimination between paedophilic and teleiophilic men may be achieved using functional activation patterns. Nevertheless, the heterogeneous findings published so far suggest further research is necessary to disentangle the neurobiological mechanisms of paedophilic preference. A number of methodological confounds have been identified, which may account for the inconsistent results that could prove to be beneficial for future investigations.

The impact of alcohol dependence on social brain function.

The impact of alcoholism (ALC) or alcohol dependence on the neural mechanisms underlying cognitive and affective empathy (i.e. the different routes to understanding other peoples minds) in schizophrenic patients and non‐schizophrenic subjects is still poorly understood. We therefore aimed at determining the extent to which the ability to infer other peoples mental states and underlying neural mechanisms were affected by ALC. We examined 48 men, who suffered either from ALC, schizophrenia, both disorders or none of these disorders, using functional magnetic resonance imaging while performing on a mind reading task that involves both cognitive and affective aspects of empathy. Using voxel‐based morphometry, we additionally examined whether between‐group differences in functional activity were associated with deficits in brain structural integrity. During mental state attribution, all clinical groups as compared with healthy controls exhibited poor performance as well as reduced right‐hemispheric insular function with the highest error rate and insular dysfunction seen in the schizophrenic patients without ALC. Accordingly, both behavioral performance and insular functioning revealed schizophrenia × ALC interaction effects. In addition, schizophrenic patients relative to non‐schizophrenic subjects (regardless of ALC) exhibited deficits in structural integrity and task‐related recruitment of the left ventrolateral prefrontal cortex (vlPFC). Our data suggest that ALC‐related impairment in the ability to infer other peoples mental states is limited to insular dysfunction and thus deficits in affective empathy. By contrast, mentalizing in schizophrenia (regardless of ALC) may be associated with insular dysfunction as well as a combination of structural and functional deficits in the left vlPFC.

Neurocognitive and personality factors in homo- and heterosexual pedophiles and controls.

INTRODUCTION Several neuropsychological studies have suggested an association between pedophilia, neurocognitive disturbances, and specific personality profiles. However, inconsistencies in the findings have not been explained sufficiently, because many studies did not control for possible confounding factors, such as age, education level, or gender orientation. AIM Therefore, the present investigation examined neurocognitive performance and personality profiles in pedophiles in dependence of sexual gender preferences and sexual deviance, as well as with regard to age and education level. MAIN OUTCOME MEASURES Scores on the different neurocognitive tests, personality questionnaires, and Structured Clinical Interview for the Diagnostic and Statistical Manual of Mental Disorders (DSM)-IV (SCID) interviews. METHODS An extensive neurocognitive test battery (including a reduced version of the German Wechsler Adult Intelligence Scale, the Wisconsin card-sorting test, d2 Attention-Deficit Test, and the Corsi block-tapping test) as well as two personality questionnaires (Minnessota Multiphasic Personality Inventory [MMPI-2] and the Multiphasic Sex Inventory [MSI]) were used to examine a consecutive sample of 20 psychiatrically assessed (SCID I and II) pedophile inpatients (nine exclusively attracted to females and 11 to males) from two high security forensic hospitals and 28 healthy controls (14 heterosexual, 14 homosexual). RESULTS Compared with controls, pedophiles showed neurocognitive impairments and personality specifics in the majority of tests and questionnaires, such as reduced values on the intelligence scale and weaker performances in information processing, together with high scores for psychopathy and paranoia, and signs of sexual obsessiveness and sexual dysfunction. In contrast to previous reports, some of these alterations were at least partly explained by factors other than pedophilia, such as education level or age. CONCLUSION These alterations may be seen to be in line with the hypothesis of a perturbation of neurodevelopment in early life. These results enhance our knowledge about pedophilia-associated impairment in neurocognitive functioning and personality structure insofar as they allow a more detailed description of, and insight into, modulatory factors.

The Neurobiology and Psychology of Pedophilia: Recent Advances and Challenges

A pedophilic disorder is recognized for its impairment to the individual and for the harm it may cause to others. Pedophilia is often considered a side issue and research into the nature of pedophilia is delayed in comparison to research into other psychiatric disorders. However, with the increasing use of neuroimaging techniques, such as functional and structural magnetic resonance imaging (sMRI, fMRI), together with neuropsychological studies, we are increasing our knowledge of predisposing and accompanying factors contributing to pedophilia development. At the same time, we are faced with methodological challenges, such as group differences between studies, including age, intelligence, and comorbidities, together with a lack of careful assessment and control of child sexual abuse. Having this in mind, this review highlights the most important studies investigating pedophilia, with a strong emphasis on (neuro-) biological studies, combined with a brief explanation of research into normal human sexuality. We focus on some of the recent theories on the etiology of pedophilia such as the concept of a general neurodevelopmental disorder and/or alterations of structure and function in frontal, temporal, and limbic brain areas. With this approach, we aim to not only provide an update and overview but also a framework for future research and to address one of the most significant questions of how pedophilia may be explained by neurobiological and developmental alterations.