Schiffer Boris, Paul Thomas, Gizewski Elke, Forsting Michael, Leygraf Norbert, Schedlowski Manfred, Kruger Tillmann H C
Department of Forensic Psychiatry, University Hospital Essen, University of Duisburg-Essen, Germany.
Neuroimage. 2008 May 15;41(1):80-91. doi: 10.1016/j.neuroimage.2008.02.008. Epub 2008 Feb 20.
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.
尽管最近已对正常性动机和功能背后的神经元机制进行了研究，但诸如恋童癖等异常性行为中脑功能的改变在很大程度上仍不为人知。本研究的目的是确定与性唤起有关的恋童癖特异性功能网络。因此，连续选取了八名仅对女性有吸引力的恋童癖法医住院患者，以及12名来自可比社会经济阶层、年龄匹配的健康异性恋对照参与者，在功能磁共振成像期间参与视觉性刺激程序。视觉刺激包括性刺激照片和情绪中性照片。成像 session 后立即记录与性欲有关的主观反应。原则上，异性恋恋童癖者对恋童癖刺激的大脑反应与异性恋男性对异性刺激的反应相当，包括不同的边缘结构（杏仁核、扣带回和海马体）、黑质、尾状核，以及前扣带回皮质、不同的丘脑核和联合皮质。然而，在健康异性恋男性中，眶额皮质对视觉性刺激有反应，而在恋童癖者中则没有，在恋童癖者中观察到背外侧前额叶皮质有异常活动。因此，与临床观察和神经心理学研究一致，异性恋恋童癖者对性刺激的中枢处理似乎可能因前额叶网络的紊乱而改变，正如已经假设的那样，这可能与受刺激控制的行为，如性强迫行为有关。此外，这些发现可能表明在性唤起处理的认知阶段存在功能障碍（在功能和有效连接方面）。
