Brain Functional Biomarkers Distinguishing Premature Ejaculation From Anejaculation by ALFF: A Resting-State fMRI Study

IntroductionPremature ejaculation (PE) and anejaculation (AJ) are 2 opposite disorders of male ejaculatory dysfunction. Recent studies have demonstrated that the process of ejaculation is mediated by certain neural circuits in the brain. However, different mechanisms between PE and AJ are still unclear.AimTherefore, we used resting-state functional magnetic resonance imaging (fMRI) to explore the underlying neural mechanisms in patients with PE and AJ by measuring the amplitude of low-frequency fluctuations (ALFF).MethodsResting-state fMRI data were acquired in 17 PE, 20 AJ patients and 23 matched healthy controls (HC).Main Outcome MeasureDifferences of ALFF values among the 3 groups were compared. We also explored the correlations between brain regions showing altered ALFF values and scores of Premature Ejaculation Diagnostic Tool (PEDT) in the PE group.ResultsThere were widespread differences of ALFF values among the 3 groups, which included left anterior cingulate gyrus, precentral and postcentral gyrus, paracentral lobule, superior temporal gyrus, calcarine fissure, putamen; right postcentral gyrus, paracentral lobule, middle temporal gyrus, putamen. Compared with HC, PE patients had greater ALFF in the right inferior frontal gyrus (opercular part), AJ patients had greater ALFF in the left postcentral gyrus. In addition, PE patients exhibited greater ALFF in the left Rolandic operculum, anterior cingulate gyrus, inferior frontal gyrus (orbital part), putamen, and right putamen when compared with AJ patients, as well as decreased ALFF in the right postcentral gyrus. Moreover, positive correlations were found between ALFF of left postcentral gyrus, inferior frontal gyrus (orbital part), right inferior frontal gyrus (opercular part), and PEDT scores.Clinical ImplicationsThe differences in central pathophysiological mechanisms between PE and AJ might be useful for improving the clinical diagnosis of ejaculation dysfunction.Strength & LimitationsOur results showed that the method of fMRI could identify the differences of ALFF between PE and AJ and that these alterations in ALFF were related to clinical function. However, this was a relatively small sample study, and further multimodal neuroimaging studies with large samples were needed.ConclusionThe findings demonstrated that altered ALFF of frontal, parietal cortex, and putamen might help distinguish premature ejaculation from anejaculation. Abnormal function of these brain regions might play a critical role in the physiopathology of ejaculatory dysfunction of patients.Chen J, Yang J, Huang X, et al. Brain Functional Biomarkers Distinguishing Premature Ejaculation From Anejaculation by ALFF: A Resting-State fMRI Study. J Sex Med 2020;17:2331–2340.     

Gray Matter Volume Differences in Impulse Control and Addictive Disorders—An Evidence From a Sample of Heterosexual Males

BackgroundsThe classification of addictions and impulse control disorders is changing as reflected in the 11th version of International Classification of Disorders (WHO, 2018). However, studies focusing on direct comparison of structural brain differences in behavioral and substance addictions are limited.AimHere, we contrast gray matter volumes (GMVs) across groups of individuals with compulsive sexual behavior disorder (CSBD), gambling disorder (GD), and alcohol use disorder (AUD) with those with none of these disorders (healthy controls participants; HCs).MethodsVoxel-based morphometry was used to study brain structure, and severities of addiction symptoms were assessed with questionnaires. To identify brain regions related to severities of addictions, correlations between questionnaire scores and GMVs were computed.Main OutcomeWe collected magnetic resonance imaging (GMVs) data from 26 patients with CSBD, 26 patients with GD, 21 patients with AUD, and 25 HC participants (all heterosexual males; age: 24-60; mean = 34.5, standard deviation = 6.48).ResultsAffected individuals (CSBD, GD, AUD) compared with HC participants showed smaller GMVs in the left frontal pole, specifically in the orbitofrontal cortex. The most pronounced differences were observed in the GD and AUD groups, and the least in the CSBD group. In addition, a negative correlation was found between GMVs and disorder severity in the CSBD group. Higher severity of CSBD symptoms was correlated with decreased GMVs in the right anterior cingulate gyrus.Clinical ImplicationsOur findings suggest similarities between CSBD and addictions.Strenghs and LimitiationsThis study is the first showing smaller GMVs in 3 clinical groups of CSBD, GD, and AUD. But the study was limited only to heterosexual men. Longitudinal studies should examine the extent to which ventral prefrontal decrements in volume may represent preexisting vulnerability factors or whether they may develop with disorder progression.ConclusionsOur research extends prior findings in substance use disorders of lower GMVs in prefrontal cortical volumes among 3 clinical groups of patients with specific impulse control (CSBD) and behavioral (GD) and substance (AUD) addictive disorders. The negative correlation between CSBD symptoms and GMV of right anterior cingulate gyrus suggests a link with clinical symptomatology.Draps M, Sescousse G, Potenza MN, et al. Gray Matter Volume Differences in Impulse Control and Addictive Disorders—An Evidence From a Sample of Heterosexual Males. J Sex Med 2020;17:1761–1769.     

Differing Default Mode Network Activities in Men with Homosexual or Heterosexual Preferences

IntroductionNeuroimaging studies have reported differences in brain structure and function between homosexual and heterosexual men. The neural basis for homosexual orientation, however, is still unknown.AimThis study characterized the association of homosexual preference with measures of fractional amplitude of low‐frequency fluctuation (fALFF) and functional connectivity (FC) in the resting state.MethodsWe collected echo planar magnetic resonance imaging data in 26 healthy homosexual men and 26 age‐matched heterosexual men in the resting state.Main Outcome MeasuresSexual orientation was evaluated using the Kinsey scale. We assessed group differences in fALFF and then, taking the identified group differences as seed regions, we compared groups on measures of FC from those seeds. The behavioral significance of the group differences in fALFF and FC was assessed by examining their associations with the Kinsey scores.ResultsCompared with heterosexual participants, homosexual men showed significantly increased fALFF in the right middle frontal gyrus and right anterior cerebellum, and decreased fALFF in the left postcentral gyrus, left lingual gyrus, right pallidum, right postcentral gyrus, left interior parietal gyrus, right superior temporal gyrus, left cuneus, and left inferior frontal gyrus. Additionally, fALFF in the left postcentral gyrus and left cuneus correlated positively with Kinsey scores in the homosexual participants. When the seeds in the left cuneus, left cuneus, and left superior parietal gyrus also had reduced FC in homosexual participants, FC correlated positively with the Kinsey scores.ConclusionsDifferences in fALFF and FC suggest male sexual preference may influence the pattern activity in the default mode network. Hu S, Xu D, Peterson BS, Wang Q, Lai J, Hu J, Wei N, Zhang M, and Xu Y. Differing default mode network activities in men with homosexual or heterosexual preferences. J Sex Med 2014;11:2474–2484.     

Functional Magnetic Resonance Imaging Detects Between-Group Differences in Neural Activation Among Men with Delayed Orgasm Compared with Normal Controls: Preliminary Report

BackgroundMechanisms underlying delayed orgasm (DO) are poorly understood; however, known effects of psychotropic medications on sexual function provides a rationale for aberrant central nervous system signaling as a cause.AimTo compare brain activation between men with normal orgasm and those with lifelong DO during sexual stimulation using brain fMRI algorithms.Methods3 subjects with self-reported life-long DO and 6 normal controls were included in this study. The International Index of Erectile Function, Male Sexual Health Questionnaire, and self-reported time to orgasm were used to assess sexual function. Subjects underwent a 3-T fMRI study while viewing 3 video clips: a neutral control (NC), a positive emotional control (EC), and a sexual condition (SC). Each video sequence was repeated 5 times, with 50-second clips presented in a randomized fashion. fMRI data were analyzed in a block design manner to determine areas of differential brain activation between groups. The Allen Brain Atlas of gene expression in the human brain was used to identify signaling pathways in the areas of differential fMRI activation between the DO and control groups.OutcomesThe primary outcome was differential activation of fMRI neural activation between groups.ResultsAnalysis of differential activation in the SC compared with the NC and EC revealed increased activation in the right frontal operculum (P = .003), right prefrontal gyrus (P = .003), and inferior occipital gyrus (P = .003). Increased activation in the right fusiform gyrus of the occipital lobe and the right hippocampus (P = .0004) was seen in the DO group compared with controls. Using the Allen Atlas of Human Brain Expression, we identified corresponding neurotransmitter receptors to this region, including adenosine receptors, muscarinic and nicotinic cholinergic receptors, cannabinoid receptors, and dopamine receptors, among others.Clinical ImplicationsLifelong DO in men may be due to abnormal neurotransmitter signaling leading to poor progression of arousal due to aberrant processing of sexual cues. Identification of neurotransmitter pathways by fMRI will aid the development of pharmacotherapeutic agents.Strengths & LimitationsStrengths of this study include the novel application of functional neuroimaging to investigate the pathogenesis of DO. Limitations include the small sample size, making this study exploratory in nature.ConclusionThis study revealed differences in brain activation on visualization of sexual stimuli in men with a history of DO compared with controls. Identified regions are rich in numerous neurotransmitter receptor subtypes and may be amenable to pharmacologic targeting to identify novel therapies for these men.Flannigan R, Heier L, Voss H, et al. Functional Magnetic Resonance Imaging Detects Between-Group Differences in Neural Activation Among Men with Delayed Orgasm Compared with Normal Controls: Preliminary Report. J Sex Med 2019:16;1246–1254.     

Brain Activity Unique to Orgasm in Women: An fMRI Analysis

BackgroundAlthough the literature on imaging of regional brain activity during sexual arousal in women and men is extensive and largely consistent, that on orgasm is relatively limited and variable, owing in part to the methodologic challenges posed by variability in latency to orgasm in participants and head movement.AimTo compare brain activity at orgasm (self- and partner-induced) with that at the onset of genital stimulation, immediately before the onset of orgasm, and immediately after the cessation of orgasm and to upgrade the methodology for obtaining and analyzing functional magnetic resonance imaging (fMRI) findings.MethodsUsing fMRI, we sampled equivalent time points across female participants’ variable durations of stimulation and orgasm in response to self- and partner-induced clitoral stimulation. The first 20-second epoch of orgasm was contrasted with the 20-second epochs at the beginning of stimulation and immediately before and after orgasm. Separate analyses were conducted for whole-brain and brainstem regions of interest. For a finer-grained analysis of the peri-orgasm phase, we conducted a time-course analysis on regions of interest. Head movement was minimized to a mean less than 1.3 mm using a custom-fitted thermoplastic whole-head and neck brace stabilizer.OutcomesTen women experienced orgasm elicited by self- and partner-induced genital stimulation in a Siemens 3-T Trio fMRI scanner.ResultsBrain activity gradually increased leading up to orgasm, peaked at orgasm, and then decreased. We found no evidence of deactivation of brain regions leading up to or during orgasm. The activated brain regions included sensory, motor, reward, frontal cortical, and brainstem regions (eg, nucleus accumbens, insula, anterior cingulate cortex, orbitofrontal cortex, operculum, right angular gyrus, paracentral lobule, cerebellum, hippocampus, amygdala, hypothalamus, ventral tegmental area, and dorsal raphe).Clinical TranslationInsight gained from the present findings could provide guidance toward a rational basis for treatment of orgasmic disorders, including anorgasmia.Strengths and LimitationsThis is evidently the first fMRI study of orgasm elicited by self- and partner-induced genital stimulation in women. Methodologic solutions to the technical issues posed by excessive head movement and variable latencies to orgasm were successfully applied in the present study, enabling identification of brain regions involved in orgasm. Limitations include the small sample (N = 10), which combined self- and partner-induced stimulation datasets for analysis and which qualify the generalization of our conclusions.ConclusionExtensive cortical, subcortical, and brainstem regions reach peak levels of activity at orgasm.Wise NJ, Frangos E, Komisaruk BR. Brain Activity Unique to Orgasm in Women: An fMRI Analysis. J Sex Med 2017;14:1380–1391.     

Effects of Cross-Sex Hormone Treatment on Cortical Thickness in Transsexual Individuals

IntroductionUntreated transsexuals have a brain cortical phenotype. Cross-sex hormone treatments are used to masculinize or feminize the bodies of female-to-male (FtMs) or male-to-female (MtFs) transsexuals, respectively.AimA longitudinal design was conducted to investigate the effects of treatments on brain cortical thickness (CTh) of FtMs and MtFs.MethodsThis study investigated 15 female-to-male (FtMs) and 14 male-to-female (MtFs) transsexuals prior and during at least six months of cross-sex hormone therapy treatment. Brain MRI imaging was performed in a 3-Tesla TIM-TRIO Siemens scanner. T1-weighted images were analyzed with FreeSurfer software to obtain CTh as well as subcortical volumetric values.Main Outcome MeasuresChanges in brain CTh thickness and volumetry associated to changes in hormonal levels due to cross-sex hormone therapy.ResultsAfter testosterone treatment, FtMs showed increases of CTh bilaterally in the postcentral gyrus and unilaterally in the inferior parietal, lingual, pericalcarine, and supramarginal areas of the left hemisphere and the rostral middle frontal and the cuneus region of the right hemisphere. There was a significant positive correlation between the serum testosterone and free testosterone index changes and CTh changes in parieto-temporo-occipital regions. In contrast, MtFs, after estrogens and antiandrogens treatment, showed a general decrease in CTh and subcortical volumetric measures and an increase in the volume of the ventricles.ConclusionsTestosterone therapy increases CTh in FtMs. Thickening in cortical regions is associated to changes in testosterone levels. Estrogens and antiandrogens therapy in MtFs is associated to a decrease in the CTh that consequently induces an enlargement of the ventricular system.Zubiaurre-Elorza L, Junque C, Gómez-Gil E, and Guillamon A. Effects of cross-sex hormone treatment on cortical thickness in transsexual individuals. J Sex Med 2014;11:1248–1261.     

Different Neural Correlates of Sexually Preferred and Sexually Nonpreferred Stimuli

BackgroundThe differences and relationships between stimulus-related brain activation for sexually preferred stimuli and sexually nonpreferred stimuli are still unclear.AimThis study aimed to identify brain regions that were mostly associated with sexual stimuli.MethodsWe used the activation likelihood estimation, meta-analytic connectivity modelling, and behavioral domain metadata in the BrainMap database to perform this analysis.OutcomesWe found convergent activation foci and created a model for the extended brain network involved in responses to sexual stimuli and also assessed the functional properties of these regions.ResultsA total of 34 experiments from 15 studies including 368 subjects and 343 foci were analyzed. The results showed that sexual stimuli are related to the extensive activation of the occipital-temporal-limbic system and less extensive activation of the basal ganglia. Sexually preferred stimuli activated mainly the anterior cingulate cortex and right fusiform gyrus, while sexually nonpreferred stimuli activated the limbic system, occipital gyrus, and thalamus.Clinical ImplicationsTo have a further understanding of the central mechanisms of human sexuality.Strengths & LimitationsPatient characteristics and analysis techniques in the included studies were heterogeneous.ConclusionsThese findings suggest that the anterior cingulate cortex is an important cognitive control area for both sexually preferred and nonpreferred stimuli. Meta-analytic connectivity modelling analysis revealed a network of the core brain areas involved in response to sexual stimuli, and behavioral domain analysis indicated that these areas have both common and discrete functional properties.Long X, Tian F, Zhou Y, et al. Different Neural Correlates of Sexually Preferred and Sexually Nonpreferred Stimuli. J Sex Med 2020;17:1254–1267.     

A quantitative meta-analysis on cue-induced male sexual arousal

IntroductionVisually induced sexual arousal is a common occurrence in human behavior. The cerebral underpinnings of this response have been explored in recent neuroimaging studies.AimWe set out to test the strength of evidence for the presence of a core network of brain regions involved in male sexual arousal elicited by erotic stimuli.MethodsEleven functional magnetic resonance imaging studies that presented erotic visual stimuli and compared the associated brain activity with the brain activity elicited by neutral visual stimuli were identified.Main Outcomes MeasuresActivation likelihood estimation was employed to perform quantitative meta‐analyses on coordinates of brain activation in order to assess significant concordance across studies.ResultsThe meta‐analysis included studies on heterosexual males and revealed consistent activation in the hypothalamus, thalamus, amygdala, anterior cingulate gyrus (ACC), insula, fusiform gyrus, precentral gyrus, parietal cortex, and occipital cortex across studies. Moreover, we explored brain responses associated with a physiological marker of sexual arousal (penile tumescence) and found concurrence in hypothalamus, thalamus, bilateral insula, ACC, postcentral gyrus, and occipital gyrus.ConclusionsThis is the first quantitative meta‐analysis on sexual cue reactivity and identifies a neural network consisting of cognitive (parietal cortex, ACC, thalamus, insula), emotional (amygdala, insula), motivational (precentral gyrus, parietal cortex), and physiological (hypothalamus/thalamus, insula) components constituting a core circuit of male sexual arousal in humans. Kühn S and Gallinat J. A quantitative meta‐analysis on cue‐induced male sexual arousal. J Sex Med 2011;8:2269–2275.     

Neural bases of hypoactive sexual desire disorder in women: an event-related FMRI study

IntroductionAlthough there is an abundant debate regarding the mechanisms sustaining one of the most common sexual complaints among women, i.e., female hypoactive sexual desire disorder (HSDD), little remains known about the specific neural bases of this disorder.AimThe main goal of this study was to determine whether women with HSDD showed differential patterns of activation within the brain network that is active for sexual desire in subjects without HSDD.MethodsA total of 28 right‐handed women participated in this study (mean age 31.1 ± 7.02 years). Thirteen out of the 28 women had HSDD (HSDD participants), while 15 women reported no hypoactive sexual desire disorder (NHSDD participants). Using event‐related functional magnetic resonance imaging (fMRI), we compared the regional cerebral blood flow responses between these two groups of participants, while they were looking at erotic vs. non‐erotic stimuli.Main Outcome MeasureBlood‐oxygenation level dependent (BOLD) signal changes in response to erotic stimuli (compared with non‐erotic stimuli). Statistical Parametric Mapping was used to identify brain regions that demonstrated significant differential activations between stimuli and between groups.ResultsAs expected, behavioral results showed that NHSDD participants rated erotic stimuli significantly higher than HSDD participants did on a 10‐point desirable scale. No rating difference was observed for the non‐erotic stimuli between NHSDD and HSDD participants. Our functional neuroimaging results extended these data by demonstrating two distinct types of neural changes in participants with and without HSDD. In comparison with HSDD participants, participants without HSDD demonstrated more activation in brain areas involved in the processing of erotic stimuli, including intraparietal sulcus, dorsal anterior cingulate gyrus, and ento/perirhinal region. Interestingly, HSDD participants also showed additional activations in brain areas associated with higher order social and cognitive functions, such as inferior parietal lobule, inferior frontal gyrus, and posterior medial occipital gyrus.ConclusionTogether, these findings indicate that HSDD participants do not only show a hypo activation in brain areas mediating sexual desire, but also a different brain network of hyper activation, which might reflect differences in subjective, social, and cognitive interpretations of erotic stimuli. Collectively, these data are in line with the incentive motivation model of sexual functioning. Bianchi‐Demicheli F, Cojan Y, Waber L, Recordon N, Vuilleumier P, and Ortigue S. Neural bases of hypoactive sexual desire disorder in women: An event‐related fMRI study. J Sex Med 2011;8:2546–2559.     

Reduced Gray Matter Volume and Increased White Matter Fractional Anisotropy in Women with Hypoactive Sexual Desire Disorder

IntroductionModels of hypoactive sexual desire disorder (HSDD) imply altered central processing of sexual stimuli. Imaging studies have identified areas which show altered processing as compared with controls, but to date, structural neuroanatomical differences have not been described.AimThe aim of this study is to investigate differences in brain structure between women with HSDD and women with no history of sexual dysfunction, and to determine sexual behavioral correlates of identified structural deviations.MethodsSexual functioning and gray matter (GM) and white matter (WM) were assessed in 29 women with HSDD and 16 healthy control subjects of comparable age and socioeconomic status with no history of sexual dysfunction.Main Outcome MeasuresWM properties were measured using diffusion‐weighted imaging and analyzed using fractional anisotropy (FA). GM volume was measured using three‐dimensional T1‐weighted recordings and analyzed using voxel‐based morphometry. Sexual functioning was measured using the Sexual Function Questionnaire.ResultsWomen with HSDD, as compared with controls, had reduced GM volume in the right insula, bilateral anterior temporal cortices, left occipitotemporal cortex, anterior cingulate gyrus, and right dorsolateral prefrontal cortex. Also, increased WM FA was observed within, amongst others, the bilateral amygdalae. Sexual interest and arousal correlated mostly with GM volume in these regions, whereas orgasm function correlated mostly with WM FA.ConclusionHSDD coincides with anatomical differences in the central nervous system, in both GM and WM. The findings suggest that decreased salience attribution to sexual stimuli, decreased perception of bodily responses and sexual emotional stimulus perception, and concomitant altered attentional mechanisms associated with sexual response induction. Bloemers J, Scholte HS, van Rooij K, Goldstein I, Gerritsen J, Olivier B, and Tuiten A. Reduced gray matter volume and increased white matter fractional anisotropy in women with hypoactive sexual desire disorder. J Sex Med 2014;11:753–767.     

The effect of combined hormonal contraceptives use on brain reactivity during response inhibition

Objectives Cognitive control, which can be described as the ability to moderate impulses, has not previously been investigated in users of combined hormonal contraception (CHC). Given the suggested modulatory role of ovarian steroids in prefrontal dopaminergic function, which in turn taps into cognitive control, this randomised, double-blinded, placebo-controlled oral contraceptive trial set out to investigate the brain activity pattern during response inhibition in CHC users.

Methods Thirty-four women were randomised to one treatment cycle with a levonorgestrel-containing CHC or placebo. The women performed a Go/NoGo task to measure brain activity during response inhibition by use of event-related functional magnetic resonance imaging (fMRI) prior to and during the CHC/placebo treatment cycle.

Results No differences between CHC and placebo users in number of correct inhibitions were found during treatment, but only women on CHC significantly improved their performance between the baseline and treatment assessments. During the treatment cycle CHC users displayed decreased activity in the right middle frontal gyrus in comparison with placebo users. No other significant activations were evident between treatment groups or within groups.

Conclusion Overall, CHC use had marginal effects on brain activity during response inhibition. If anything, the findings of the study may suggest reduced effort or increased efficiency in maintaining orbitofrontal cortex inhibitory cognitive control when using a combined oral contraceptive.     

Pedophilic behavior from brain disease

IntroductionChild molestation or other pedophilic behavior may result as a consequence of a brain disorder.AimTo characterize the mechanisms of pedophilic behavior associated with neurological diseases.MethodsWe report eight patients with pedophilic behavior as a manifestation of their brain disorder and review the literature.Main Outcome MeasuresThe sexual, neuropsychiatric, and neurological aspects of a series of patients.ResultsAll eight developed sexual behavior toward prepubescent children in mid‐ to late‐life coincident with the development of a neurological disorder. Five had limited insight, anxiety, or concern for their behavior and tended to have frontal lobe executive deficits. Most of this group had frontally predominant disorders. Two others retained insight and concern in the context of marked hypersexuality. This second group had treated Parkinson's disease and resembled reports of pedophilic behavior from subcortical lesions. The further presence of right temporal lobe‐amygdala involvement may have predisposed to specific sexual preoccupation in some patients.ConclusionsBrain disorders may release a predisposition to sexual attraction for children through disinhibition with frontal disease, sexual preoccupation with right temporal disease, or hypersexuality with subcortical disease in non‐motor basal ganglia, hypothalamus, or septal nuclei. Differentiating these mechanisms of pedophilic behavior from brain disease could facilitate targeted interventions. Mendez M and Shapira JS. Pedophilic behavior from brain disease.     

Are There Differences in Brain Morphology in Patients with Lifelong Premature Ejaculation?

IntroductionEven though lifelong premature ejaculation (PE) is highly prevalent, few studies have investigated the neural mechanisms underlying PE.AimThis study aimed to investigate whether patients with lifelong PE exhibit macrostructural or microstructural alterations of the parts of the brain involved in the male sexual response.Materials and MethodsWe enrolled 42 healthy participants and 54 lifelong PE patients. Lifelong PE was diagnosed according to the Premature Ejaculation Diagnostic Tool (PEDT) and intravaginal ejaculation latency time (IELT). We compared measures of cortical morphology, such as volumes of gray matter, white matter, cerebellum volumes, and subcortical structures (ie, amygdala, caudate, hippocampus, globus pallidus, putamen, and thalamus) between the groups using a voxel-based morphometry method from whole-brain T1-weighted magnetic resonance imaging. Moreover, we evaluated the relationships between the relevant cerebral alterations and the severity of symptoms obtained from participants via self-reported questionnaires.Main Outcome MeasuresCerebral macrostructural and microstructural alterations were assessed in PE patients and controls, along with the correlation of caudate nucleus changes in PE patients with clinical data (including the PEDT and the IELT).ResultsThe mean volume of the caudate nucleus was significantly larger in the lifelong PE patients compared with healthy controls (P = .048). Moreover, caudate nucleus volume was positively correlated with PEDT score (r = 0.621; P = .0179) and negatively correlated with the IELT (r = ?0.592; P = .0101). However, cortex morphology and the other subcortical volumes were not significantly different between the 2 groups (P > .05).Clinical ImplicationsMicrostructural alterations in deep gray matter nuclei might be a useful parameter for studying the mechanism of the neurobiology underlying PE.Strengths and LimitationsThere are few studies examining microstructural changes in PE patients. This study furthers our understanding of the etiology of PE. Limitations include the small sample, which limits our ability to make an absolute determination as to whether such subcortical changes are the cause or the consequence of lifelong PE.ConclusionsWe found a significant difference in caudate nucleus volume between patients with PE and healthy controls. In addition, the caudate nucleus volume was positively associated with the severity of PE symptoms. More extensive and possibly longitudinal studies are needed to improve our understanding of the mechanism of the neurobiology underlying PE.Atalay HA, Sonkaya AR, Ozbir S, et al. Are There Differences in Brain Morphology in Patients with Lifelong Premature Ejaculation? J Sex Med 2019;16:992–998.     

Effect of Sex Hormones on Brain Connectivity Related to Sexual Function in Perimenopausal Women: A Resting-State fMRI Functional Connectivity Study

Background

Perimenopause is associated with increased risk of depression, vasomotor symptoms, and sexual dysfunction.

Functional cortical and subcortical abnormalities in pedophilia: a combined study using a choice reaction time task and fMRI

IntroductionPedophiles show sexual interest in prepubescent children but not in adults. Research into the neurofunctional mechanisms of paraphilias has gathered momentum over the last years.AimTo elucidate the underlying neural processing of sexual interest among pedophiles and to highlight the differences in comparison with nonparaphilic sexual interest in adults.MethodsNine pedophilic patients and 11 nonpedophilic control subjects underwent functional magnetic resonance imaging (fMRI) while viewing pictures of nude (prepubescents, pubescents, and adults) and neutral content, as well as performing a concomitant choice reaction time task (CRTT).Main Outcome MeasuresBrain blood oxygen level-dependent (BOLD) signals and response latencies in the CRTT during exposure to each picture category.ResultsAnalysis of behavioral data showed group differences in reaction times regarding prepubescent and adult but not pubescent stimuli. During stimulation with pictures displaying nude prepubescents, pedophiles showed increased BOLD response in brain areas known to be involved in processing of visual sexual stimuli. Comparison of pedophilic patients with the control group discovered differences in BOLD responses with respect to prepubescent and adult but not to pubescent stimuli. Differential effects in particular occurred in the cingulate gyrus and insular region.ConclusionsThe brain response of pedophiles to visual sexual stimulation by images of nude prepubescents is comparable with previously described neural patterns of sexual processing in nonpedophilic human males evoked by visual stimuli depicting nude adults. Nevertheless, group differences found in the cingulate gyrus and the insular region suggest an important role of these brain areas in pedophilic sexual interest. Furthermore, combining attention-based methods like CRTT with fMRI may be a viable option for future diagnostic procedures regarding pedophilia. Poeppl TB, Nitschke J, Dombert B, Santtila P, Greenlee MW, Osterheider M, and Mokros A. Functional cortical and subcortical abnormalities in pedophilia: A combined study using a choice reaction time task and fMRI.     

隐源性婴儿痉挛患儿脑磁共振形态学定量分析

目的通过定量分析隐源性婴儿痉挛患儿脑灰质结构，寻找其发病原因和探讨发病机制。 方法使用无创性的MR形态学定量对比分析技术，对2003-10—2004-10北京儿童医院23例隐源性婴儿痉挛(观察组)和27例同龄健康儿童(对照组)脑部高分辨解剖成像，进行灰质浓度的测定，比较两组之间的差异。 结果两组灰质浓度比较，观察组在右额上回(10区)和中回(9区)、左额下回(47区)和上回(9、10区)、左额内侧(10区)、右颞上回(22、38区)、左颞中回(21区)以及右侧海马(36区)等灰质浓度减低，差异有显著性意义，P<0001(未校正)；双侧颞下回(20区)、左侧中央前回(6区)和左海马(36区)研究组灰质浓度增高，差异有显著性意义，P<0001(未校正)。 结论隐源性婴儿痉挛患儿额叶和颞叶灰质浓度明显减低，以额叶和颞叶为主的皮层发育不良可能是患儿致病的主要原因；在发病机制中皮层异常是发病的起源。     

The Role of Left Superior Parietal Lobe in Male Sexual Behavior: Dynamics of Distinct Components Revealed by fMRI

IntroductionDespite the interest for the brain correlates of male sexual arousal, few studies investigated neural mechanisms underlying psychogenic erectile dysfunction (ED). Although these studies showed several brain regions active in ED patients during visual erotic stimulation, the dynamics of inhibition of sexual response is still unclear.AimThis study investigated the dynamics of brain regions involved in the psychogenic ED.MethodsFunctional magnetic resonance imaging (fMRI) and simultaneous penile tumescence (PT) were used to study brain activity evoked in 17 outpatients with psychogenic ED and 19 healthy controls during visual erotic stimulation. Patterns of brain activation related to different phases of sexual response in the two groups were compared.Main Outcome MeasuresSimultaneous recording of blood oxygen level-dependent fMRI responses and PT during visual erotic stimulation.ResultsDuring visual erotic stimuli, a larger activation was observed for the patient group in the left superior parietal lobe, ventromedial prefrontal cortex, and posterior cingulate cortex, whereas the control group showed larger activation in the right middle insula and dorsal anterior cingulate cortex and hippocampus. Moreover, the left superior parietal lobe showed a larger activation in patients than controls especially during the later stage of sexual response.ConclusionsOur results suggest that, among regions more active in patient group, the left superior parietal lobe plays a crucial role in inhibition of sexual response. Previous studies showed that left superior parietal lobe is involved in monitoring of internal body representation. The larger activation of this region in patients during later stages of sexual response suggests a high monitoring of the internal body representation, possibly affecting the behavioral response. These findings provide insight on brain mechanisms involved in psychogenic ED. Cera N, Di Pierro ED, Sepede G, Gambi F, Perrucci MG, Merla A, Tartaro A, Del Gratta C, Galatioto Paradiso G, Vicentini C, Romani GL, and Ferretti A. The role of left superior parietal lobe in male sexual behavior: Dynamics of distinct components revealed by fMRI. J Sex Med 2012;9:1602–1612.     

ORIGINAL RESEARCH—EJACULATORY DISORDERS: Quantitative Sensory Testing of Peripheral Thresholds in Patients with Lifelong Premature Ejaculation: A Case-Controlled Study

IntroductionThe main functional factors related to lifelong premature ejaculation (PE) etiology have been suggested to be penile hypersensitivity, greater cortical penile representation, and disturbance of central serotoninergic neurotransmission.AimsTo quantitatively assess penile sensory thresholds in European Caucasian patients with lifelong PE using the Genito-Sensory Analyzer (GSA, Medoc, Ramat Yishai, Israel) as compared with those of an age-comparable sample of volunteers without any ejaculatory compliant.MethodsForty-two consecutive right-handed, fully potent patients with lifelong PE and 41 right-handed, fully potent, age-comparable volunteers with normal ejaculatory function were enrolled. Each man was assessed via comprehensive medical and sexual history; detailed physical examination; subjective scoring of sexual symptoms with the International Index of Erectile Function; and four consecutive measurements of intravaginal ejaculatory latency time with the stopwatch method. All men completed a detailed genital sensory evaluation using the GSA; thermal and vibratory sensation thresholds were computed at the pulp of the right index finger, and lateral aspect of penile shaft and glans, bilaterally.Main Outcome MeasuresComparing quantitatively assessed penile thermal and vibratory sensory thresholds between men with lifelong PE and controls without any ejaculatory compliant.ResultsPatients showed significantly higher (P < 0.001) thresholds at the right index finger but similar penile and glans thresholds for warm sensation as compared with controls. Cold sensation thresholds were not significantly different between groups at the right index finger or penile shaft, but glans thresholds for cold sensation were bilaterally significantly lower (P = 0.01) in patients. Patients showed significantly higher (all P ≤ 0.04) vibratory sensation thresholds for right index finger, penile shaft, and glans, bilaterally, as compared with controls.ConclusionsQuantitative sensory testing analysis suggests that patients with lifelong PE might have a hypo- rather than hypersensitivity profile in terms of peripheral sensory thresholds. The peripheral neuropathophysiology of lifelong PE remains to be clarified. Salonia A, Saccà A, Briganti A, Carro UD, Dehò F, Zanni G, Rocchini L, Raber M, Guazzoni G, Rigatti P, and Montorsi F. Quantitative sensory testing of peripheral thresholds in patients with lifelong premature ejaculation: A case-controlled study. J Sex Med 2009;6:1755–1762.     

Diminished Functional Connectivity on the Road to Child Sexual Abuse in Pedophilia

BackgroundPedophilia is a disorder recognized for its impairment to the individual and for the harm it may cause to others. However, the neurobiology of pedophilia and a possible propensity to sexually abuse children are not well understood. In this study, we thus aimed at providing new insights in how functional integration of brain regions may relate to pedophilia or child sexual abuse (CSA).MethodBy using functional magnetic resonance imaging (fMRI) technique, we compared functional connectivity at rest (RSFC) between pedophiles who engaged (P+CSA; N = 12) or did not engage (P–CSA; N = 14) in CSA and healthy controls (HCs; N = 14) within two networks: (i) the default mode network and (ii) the limbic network that has been linked to pedophilia before.ResultsPedophiles who engaged in CSA show diminished RSFC in both networks compared with HC and P–CSA. Most importantly, they showed diminished RSFC between the left amygdala and orbitofrontal as well as anterior prefrontal regions. Though significant age differences between groups could not be avoided, correlation control analysis did not provide evidence for the assumption that the RSFC effects were related to age differences.ConclusionWe found significantly diminished RSFC in brain networks critically involved in widespread motivational and socio‐emotional processes. These results extend existing models of the functional neuroanatomy of pedophilia and CSA as altered RSFC between these regions were related to CSA rather than pedophilia and thus may account for an increased propensity to engage in CSA in people suffering from pedophilia. Kärgel C, Massau C, Weiß S, Walter M, Kruger THC, and Schiffer B. Diminished functional connectivity on the road to child sexual abuse in pedophilia. J Sex Med 2015;12:783–795.