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Reports of intimate touch: Erogenous zones and somatosensory cortical organization

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... Yet, paradoxically, tactile stimulation of bodily regions with no apparent connection to the genitals, such as breasts and nipples, hasalso beenfoundtotriggersexualarousal (Levin& Meston,2006;Turnbull, Lovett, Chaldecott, & Lucas, 2014) and consequently human partners also caress each other's bodies in regions outside the genitalsduringsexual interaction.Togetherwithgenitals,suchregions are often called erogenous zones due to their capability of triggering sexual arousal. Even though tactile and nociceptive sensitivity of different bodily regions is well understood (Ackerley, Carlsson, Wester, Olausson, & Backlund Wasling, 2014;Mancini et al., 2014), the quantitative topographical layout as well as functions of human erogenous zones has remained unresolved. ...
... Furthermore, the functional role ofthe arousal-triggeringpropertiesofthe non-genital areasispoorly understood. If sexual touching serves only a general arousal modulating function, touching patterns could be hypothesized to be focused on the genitals and be concordant during masturbation and while having sex with a partner because touching genitals triggers the most powerful arousal responses (Turnbull et al., 2014). However, if touching the partner's body during sexual interaction also serves functions unrelated to sexual arousal, it could be hypothesized that the touching patterns are different when having sex with a partner versus masturbating. ...
... However, correlating EZMs with tactile and nociceptive sensitivity maps highlighted that a region's capability for triggering sexual arousal upon touching was primarily-but not completely-determined by its tactile sensitivity, and that tactile sensitivity across the whole body is exploited only when having sex with a partner. 2 Nevertheless, the EZMs bore little resemblance to the somatosensory organization of the body in somatosensory cortices (Penfield & Boldrey, 1937;Ruben et al., 2001), with regions whose representation is close to genitals in the S1 not being significantly more prone to trigger sexual arousal than those further apart. Thus, it is unlikely that partial activation of the S1 representation of the genitals by stimulation to adjacent areas would be driving the arousal response (see also Turnbull et al., 2014). However, more complete understanding of the somatotopic organization of male and female genitals and erogenous zones in SI and SII is needed to understand the role of extragenital regions in triggering sexual arousal. ...
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Touching is a powerful means for eliciting sexual arousal. Here, we establish the topographical organization of bodily regions triggering sexual arousal in humans. A total of 704 participants were shown images of same and opposite sex bodies and asked to color the bodily regions whose touching they or members of the opposite sex would experience as sexually arousing while masturbating or having sex with a partner. Resulting erogenous zone maps (EZMs) revealed that the whole body was sensitive to sexual touching, with erogenous hotspots consisting of genitals, breasts, and anus. The EZM area was larger while having sex with a partner versus while masturbating, and was also dependent on sexual desire and heterosexual and homosexual interest levels. We conclude that tactile stimulation of practically all bodily regions may trigger sexual arousal. Extension of the erogenous zones while having sex with a partner may reflect the role of touching in maintenance of reproductive pair bonds.
... To explain this paradox, it was initially proposed that erotic sensations from these body parts arise as a consequence of their adjacency to the genitals in the somatotopic map of the primary somatosensory cortex (S1) [3]. Despite this intriguing possibility, a recent systematic investigation of erogenous zones, involving 41 different body areas, provided evidence against this hypothesis [4]. Specifically, there were no significant inter-correlations between ratings of sexual arousal for nearby S1 sites, suggesting that sexual arousal is unrelated to proximity of cortical representation of body parts in S1. ...
... Moreover, there were surprisingly low sexual arousal ratings for the feet, which are adjacent to the cortical mapping for genitals in S1. Therefore, it was suggested that the somatotopy of erogenous zones may be coded elsewhere in the brain, possibly in the insular cortex [4], as this area is involved in the re-representation of interoception offering the basis for subjective feelings [5,6]. Nevertheless, there has been no direct exploration of this hypothesis as yet. ...
... To help the Giver better understand the difference between slow and fast stroke velocities, the experimenter applied both touches on the Giver's forearm during the training phase. The body parts to which touch was applied were selected from a list of 41 body parts generated by a recent systematic review [4]. This list was divided into 3 almost-equal parts and we subsequently selected one body part from the top 14 (i.e. ...
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Previous research points to two major hypotheses regarding the mechanisms by which touch can be experienced as erotogenic. The first concerns the body part to which touch is applied (erogenous zones) and the second the modality of touch (sensual touch optimal in activating C Tactile afferents). In this study, we explored for the first time the relation between those two mechanisms in actual and imagined social touch. In a first experiment, we randomly assigned “Giver” and “Receiver” roles within 19 romantic couples (20 females, 18 males, age 32.34 ± 8.71SD years) and asked the “Giver” to apply CT-optimal (3 cm/s) vs. CT-suboptimal (18 cm/s) touch on an erogenous (neck) vs. non-erogenous zone (forehead) of their partner. We then obtained ratings of pleasantness and sexual arousal from both “Receivers” and “Givers”. In a second experiment, 32 healthy females (age 25.16 ± 5.91SD years) were asked to imagine CT-optimal vs. CT-suboptimal stimulation (stroking vs. patting) and velocity (3 cm/s vs. 18 cm/s) on different erogenous vs. non-erogenous zones and rate pleasantness. While both erogenous body part and CT-optimal, sensual touch were found to increase pleasant and erotic sensations, the results showed a lack of an interaction. Furthermore, pleasantness was induced by mere imagination of touch without any tactile stimulation, and touch that was sexually arousing for the receiver was rated as more sexually arousing for the giver as well, pointing to top-down, learned expectations of sensory pleasure and erogeneity. Taken together, these studies provide the first direct evidence that while both the body location to which touch is applied and the mode of touch contribute to pleasant and erotic sensations, these two factors appear to mediate subjective pleasantness and erogeneity by, at least partly, independent mechanisms.
... O.H. Turnbull и соавторы [34] провели специальное ис следование ЭЗ у 800 человек, проживающих на Британских островах (British Isles) и к югу от Сахары (Sub Saharan Africa). В разработку были включены 793 анкеты. ...
... Была изучена эрогенная чувствительность 41 части те ла. В перечень исследуемых зон на передней части тела во шли: лоб, глаза, веки и виски, нос, щеки, рот/губы, уши, пе Эрогенность различных частей тела мужчин и женщин, выраженная в баллах, начиная с наивысшего [34] отмечают, что утверждение, согласно которому женщи ны имеют гораздо большее количество ЭЗ высокой интен сивности, по всей видимости, имеет некоторую основу. Ре зультаты проведенного исследования также свидетельство вали, что у мужчин только одна часть тела (промежность) по рейтингу эрогенной чувствительности была оценена значи тельно выше, чем у женщин (р<0,001). ...
... O.H. Turnbull и соавторы [34] также пытаются ответить на вопрос, связано ли распределение ЭЗ с начальным пери одом развития (возможно, внутриутробным) или это резуль тат более поздних эффектов развития, в том числе культур ных переменных или индивидуальные различия жизненного опыта. Авторы предполагают, что факторы, определяющие интенсивность эрогенного отклика (эрогенную интенсив ность) ЭЗ, не сильно зависят от индивидуального жизненно го опыта и/или культуры, хотя признают необходимость проведения дальнейших исследований в этом направлении (например, в отношении возрастного диапазона и культур ного разнообразия). ...
Article
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Definitions, classifications of erogenous zones, information about various genital and extragenital erogenous zones, results of special studies concerning the rating of the sensitivity of various erogenous zones in men and women are submitted. Key words: men, women, erogenous zones, classifications, rating. В обзорной статье приведены определения, классификации эрогенных зон, сведения о различных генитальных и экстрагенитальных эрогенных зонах, данные научных исследований относительно рейтинга чувствительности различных эрогенных зон у мужчин и женщин. Ключевые слова: мужчины, женщины, эрогенные зоны, классификации, рейтинг.
... These areas can encompass up to 26% of the body surface (Nummenmaa, Suvilehto, Glerean, Santtila, & Hietanen, 2016) and are reported as arousing in the large majority of individuals (Younis et al., 2016). To date, only a small number of studies (Nummenmaa et al., 2016;Turnbull, Lovett, Chaldecott, & Lucas, 2014) have systematically mapped the tactile erogenous zones of the body. Across these studies, several extra-genital body parts were reliably identified as capable of eliciting high levels of sexual arousal: these included the breasts, nipples, lips, neck and nape of neck, ears, buttocks, and inner thigh (Nummenmaa et al., 2016;Turnbull et al., 2014;Younis et al., 2016). ...
... To date, only a small number of studies (Nummenmaa et al., 2016;Turnbull, Lovett, Chaldecott, & Lucas, 2014) have systematically mapped the tactile erogenous zones of the body. Across these studies, several extra-genital body parts were reliably identified as capable of eliciting high levels of sexual arousal: these included the breasts, nipples, lips, neck and nape of neck, ears, buttocks, and inner thigh (Nummenmaa et al., 2016;Turnbull et al., 2014;Younis et al., 2016). The topographical distribution and intensity of erogenous zones are similar for men and women (Nummenmaa et al., 2016;Turnbull et al., 2014) and are relatively impervious to sociological, demographic, and cultural factors (Turnbull et al., 2014). ...
... Across these studies, several extra-genital body parts were reliably identified as capable of eliciting high levels of sexual arousal: these included the breasts, nipples, lips, neck and nape of neck, ears, buttocks, and inner thigh (Nummenmaa et al., 2016;Turnbull et al., 2014;Younis et al., 2016). The topographical distribution and intensity of erogenous zones are similar for men and women (Nummenmaa et al., 2016;Turnbull et al., 2014) and are relatively impervious to sociological, demographic, and cultural factors (Turnbull et al., 2014). ...
Article
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Erogenous zones of the body are sexually arousing when touched. Previous investigations of erogenous zones were restricted to the effects of touch on one’s own body. However, sexual interactions do not just involve being touched, but also involve touching a partner and mutually looking at each other’s bodies. We take a novel interpersonal approach to characterize the self-reported intensity and distribution of erogenous zones in two modalities: touch and vision. A large internet sample of 613 participants (407 women) completed a questionnaire, where they rated intensity of sexual arousal related to different body parts, both on one’s own body and on an imagined partner’s body in response to being touched but also being looked at. We report the presence of a multimodal erogenous mirror between sexual partners, as we observed clear correspondences in topographic distributions of self-reported arousal between individuals’ own bodies and their preferences for a partner’s body, as well as between those elicited by imagined touch and vision. The erogenous body is therefore organized and represented in an interpersonal and multisensory way.
... Study 2 aimed to replicate the results from study 1 on the forearm and additionally tested if eroticism ratings to C tactile optimal brushing are related to sexual behavior in daily life. The forearm was chosen based on previous studies on C tactile-related perception [3,10,11], and the inner thigh was chosen based on high self-rated erotic touch perception [12]. ...
... (never, once/month or less, once a week, more than once/week, once/day or more)". Participants additionally answered the Erogenous Zone Questionnaire (EZQ), which asks about the level of sexual arousal following touch in a variety of body parts on a visual analogue scale ranging from 0 to 10 [12]. The questionnaire was translated to Swedish, implemented in MATLAB (MathWorks, Natick, MA, USA), and presented on a screen. ...
... The forearm EZQ score was found to be significantly lower than that of the inner thigh, confirming previous results [12]. However, this difference was not detected in the eroticism or pleasantness ratings following tactile stimulation. ...
Article
Intrapersonal touch is a powerful tool for communicating emotions and can among many things evoke feelings of eroticism and sexual arousal. The peripheral neural mechanisms of erotic touch signaling have been less studied. C tactile afferents (unmyelinated low-threshold mechanoreceptors), known to underpin pleasant aspects of touch processing, have been posited to play an important role. In two studies, we investigated the relationship between C tactile activation and the perception of erotic and pleasant touch, using tactile brushing stimulation. In total, 66 healthy subjects (37 women, age range 19-51 years) were examined. In study 1 (n = 20), five different stroking velocities were applied to the forearm and the inner thigh. The participants answered questions about partnership, mood, and touch. In study 2 (n = 46), the same five stroking velocities were applied to the forearm. The participants answered questions about partnership, touch, and sexuality. Both touch eroticism and pleasantness were rated significantly higher for C tactile optimal velocities compared with suboptimal velocities. No difference was found between the ratings of the thigh and the forearm. The velocity-dependent rating curves of pleasantness, intensity, and eroticism differed from each other. Pleasantness was best explained by a quadratic fit, intensity by a linear fit, and eroticism by both. A linear transformation of pleasantness and intensity predicted the observed eroticism ratings reliably. Eroticism ratings were negatively correlated with length of relationship. Touch was rated most erotic when perceived as pleasant and weak. In human hairy skin, perception of pleasantness is correlated with the firing rate of C tactile afferents, and perception of intensity is correlated with the firing rate of Aβ afferents. Accordingly, eroticism may be perceived most readily for touch stimuli that induce high activity in C tactile fibers and low activity in Aβ fibers. Jönsson EH, Backlund Wasling H, Wagnbeck V, Dimitriadis M, Georgiadis JR, Olausson H, and Croy I. Unmyelinated tactile cutaneous nerves signal erotic sensations. J Sex Med **;**:**-**. © 2015 International Society for Sexual Medicine.
... In the introduction of their study, Turnbull et al. [5] stated the following: 'there is a striking absence of empirical research in this area (distribution of erogenous zones in normal persons based on somatic touch), and it appears that no systematic survey of the magnitude of preferred erotic sensations from various body parts has ever been published'. ...
... Following the breasts/nipples, the lips were the second most erotogenic zone in our participants, followed by the neck, the ears, the buttocks, and then the inner thigh. The only study that can be compared with our work is the study by Turnbull et al. [5], who detected the erogenous zones in 304 men and 489 women using an online questionnaire. Participants rated the ability of 41 different body areas to facilitate sexual arousal. ...
... The shin of the tibia, the nose, and elbow were the least erogenous body areas. After reporting erogenous zones found in women compared with those found in men, Turnbull et al. [5] concluded that the basis for the claim that women have a greater diversity of erogenous zones seems in part unjustified. Women clearly experience higher erotic intensity for some body parts, but this effect appears to have been exaggerated in the popular media. ...
Article
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Purpose: Erogenous zones may be genital or extragenital. Women have a greater variety of erogenous zones on the body compared with men. In the context of this article, it is important to examine this issue in conjunction with problems of sexual dysfunctions. Scientific research in the area of extragenital erogenous zones is scarce. Defining extragenital erogenous zones with the most powerful excitatory effect and how to stimulate them was the aim of this work. Participants and methods: This work was a cross-sectional cohort study wherein a self-report questionnaire was used. Usable questionnaires were obtained from 150 married women with regular sexual activity. The questions covered epidemiological data, assessment of female sexual functions, and information on extragenital erogenous zones. Results: Extragenital erogenous zones were found in 95.3% of women. In a descending order, the most powerful erogenous zones were breasts, lips, neck, ears, and buttocks. The best method for stimulation differed according to the area – for example, the best method for the lips was oral stimulation, whereas the best method for the breasts and nipples was both manual and oral stimulation. Orgasm due to the stimulation of extragenital areas was reported by 12% of participants. Conclusion: Extragenital erogenous zones are present in a vast majority of women. An overall 12% of women said that they can orgasm following stimulation of these zones. Female patients complaining of difficulty in achieving orgasm may benefit from informing their partners about the extragenital erogenous zones and methods to stimulate them.
... Defenses are, of course, imperfect solutions to protection, so that the patient will at times be unable to avoid feelings of loss, thus explaining the fluctuating nature of the patient's emotional state. Arguments of this type have previously been proposed [75][76][77][78][79][80] and have been revived in the neuroscientific literature more recently, suggesting that anosognosia might indeed be a form of defense [37,58,61,65,71,81]. Notably, in the applied field of neuropsychological rehabilitation, it is well established that the clinical presentation of anosognosic patients is a mixture of organic and psychological (defensive) factors [82][83][84][85][86][87]. ...
... A parallel research strand has long identified many subcortical emotion-related brain areas, such as the amygdala, insula, hypothalamus, and anterior cingulate (see, for example [81,[100][101][102][103]. These seem critical for other elements of emotional life, such as emotion-memory [102,103], the integration of internally generated experienced states with externally facing senses [101], or the role of loss in decision making [100]. ...
Article
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Over the last few decades, work in affective neuroscience has increasingly investigated the neural basis of emotion. A central debate in the field, when studying individuals with brain damage, has been whether emotional processes are lateralized or not. This review aims to expand this debate, by considering the need to include a hierarchical dimension to the problem. The histor- ical journey of the diverse literature is presented, particularly focusing on the need to develop a research program that explores the neural basis of a wide range of emotional processes (perception, expression, experience, regulation, decision making, etc.), and also its relation to lateralized cortical and deep-subcortical brain structures. Of especial interest is the study of the interaction between emotional components; for example, between emotion generation and emotion regulation. Finally, emerging evidence from lesion studies is presented regarding the neural basis of emotion-regulation strategies, for which the issue of laterality seems most relevant. It is proposed that, because emotion- regulation strategies are complex higher-order cognitive processes, the question appears to be not the lateralization of the entire emotional process, but the lateralization of the specific cognitive tools we use to manage our feelings, in a range of different ways.
... In 2014, Turnbull and colleagues 6 presented the first quantitative and systematic investigation of erogenous zones with the aim of testing the overlap between the distribution of erogeneity around the body and the arrangement of the body parts in the somatosensory cortex. By means of a survey, they collected data in which participants had to rate the erogenous intensity of different body parts. ...
... Interestingly, the results of the study showed that CT-optimal touch was able to convey arousal, lust and desire while affiliative emotions (such as love and social support) were induced by general pleasant touch, regardless the velocity of stroking. As to the stimulated body area, the genitals generally have the highest erotogenic potential 6,47,49,51 . However, whether CT afferents, expected to be present in the hairy skin only 52 , are present in the genitals is unknown 53 . ...
Article
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Embodying an artificial agent through immersive virtual reality (IVR) may lead to feeling vicariously somatosensory stimuli on one’s body which are in fact never delivered. To explore whether vicarious touch in IVR reflects the basic individual and social features of real-life interpersonal interactions we tested heterosexual men/women and gay men/lesbian women reacting subjectively and physiologically to the observation of a gender-matched virtual body being touched on intimate taboo zones (like genitalia) by male and female avatars. All participants rated as most erogenous caresses on their embodied avatar taboo zones. Crucially, heterosexual men/women and gay men/lesbian women rated as most erogenous taboo touches delivered by their opposite and same gender avatar, respectively. Skin conductance was maximal when taboo touches were delivered by female avatars. Our study shows that IVR may trigger realistic experiences and ultimately allow the direct exploration of sensitive societal and individual issues that can otherwise be explored only through imagination.
... In a survey based on an online Erogenous Zone Questionnaire and a scale on which 793 participants rated, in terms of level of arousal, the ability of 41 different body areas to facilitate sexual arousal (with 0: 'no erotogenic stimulation', and 10: 'highest stimulatory capacity'), the body parts with the highest scores were the clitoris (mean09.17; SD02.12) and the penis (mean 09.00; SD02.50) (Turnbull, Lovett, Chaldecott, & Lucas, 2014). ...
... Actually, there seems to be more references in the scientific literature to pain coming from female genitalia than to pleasurable sensations. In women, the neglect of scientific attention to the phenomenology of genital sensations is further complicated by the fact that both the vagina and the clitoris are erogenous zones (Turnbull, Lovett, Chaldecott, & Lucas, 2014). The scientific neglect of the phenomenology of clitoral sensations is reminiscent of the societal silence regarding the role of the clitoris, a silence that has been compared to a symbolic clitoridectomy: 'societal silence regarding the role of the clitoris may act similarly as a symbolic clitoridectomy' (Ogletree & Ginsburg, 2000). ...
Article
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Background Although genital sensations are an essential aspect of sexual behavior, the cortical somatosensory representation of genitalia in women and men remain poorly known and contradictory results have been reported. Objective To conduct a systematic review of studies based on electrophysiological and functional neuroimaging studies, with the aim to identify insights brought by modern methods since the early descriptions of the sensory homunculus in the primary somatosensory cortex (SI). Results The review supports the interpretation that there are two distinct representations of genital sensations in SI, one on the medial surface and the other on the lateral surface. In addition, the review suggests that the secondary somatosensory cortex and the posterior insula support a representation of the affective aspects of genital sensation. Conclusion In view of the erogenous character of sensations originating in the genitalia, future studies on this topic should systematically assess qualitatively as well as quantitatively the sexually stimulating and/or sexually pleasurable characteristics of sensations felt by subjects in response to experimental stimuli.
... According to the theory of Ramachandran and Blakeslee (1998), erogenous zones can be mapped in correspondence to the SI cortex. To test this hypothesis, Turnbull et al. (2014) collected data about the Erogenous Zone Questionnaire in which participants assessed the ability of each body area to facilitate sexual arousal. According to the authors, excluding genitalia or perigenital areas, the mouth-lips complex, the neck, the nipple, and the breast were assessed as erogenous by women. ...
... According to Levin and Meston (2006), most women report that the stimulation of the nipple-breast complex can facilitate sexual arousal. According to Turnbull et al. (2014), the insula represents one of the best regions in which the elaboration of erogenous zones can be processed to facilitate sexual arousal. Insula is related to affiliative and emotional touch processing (Björnsdotter et al., 2009). ...
Article
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Abstract Most of the neuroimaging studies on sexual behavior have been conducted with male participants, leading to men-based models of sexual arousal. Here, possible factors and methodological decisions that might influence brain responses to sexual stimuli, specifically for the inclusion of women, will be reviewed. Based on this review, we suggest that future studies consider the following factors: menstrual phase, hormonal contraception use, history of sexual or psychiatric disorders or diseases, and medication use. Moreover, when researching sexual arousal, we suggest future studies assess sexual orientation and preferences, that women should select visual sexual stimuli, and a longer duration than commonly used. This review is thought to represent a useful guideline for future research in sexual arousal, which hopefully will lead to a higher inclusion of women and therefore more accurate neurobiological models of sexual arousal.
... Pour des raisons physiologiques actuellement mal connues, d'autres zones corporelles (anales, orales, mais aussi les seins, l'intérieur des cuisses, la nuque. . .) peuvent devenir érogènes (Turnbull et al., 2013) puis être l'objet d'activités d'autostimulation. En raison des grandes capacités d'apprentissages de l'être humain, des émotions et surtout des représentations cognitives peuvent être associées aux activités autoérotiques. ...
... Puis après la naissance les activités autoérotiques -et tout particulièrement la masturbation -se développeraient spontanément et graduellement dès les premières années de la vie, en raison de la grande érogénéité du pénis et du clitoris (Turnbull et al., 2013 ;Wunsch, 2007), de la disposition anatomique adéquate des membres supérieurs et surtout des mains, ainsi que des récompenses cérébrales produites par les premières autostimulations génitales. Ces premières activités autoérotiques entraîneraient un développement des circuits neurobiologiques sexuels (vérifié chez les rongeurs (Moore, 1984 ;Moore et al., 1992), très probable chez l'humain (Yates, 2004)), ce qui renforcerait le développement sexuel (Yates, 1990). ...
Article
L’objectif de cet article est de préciser les facteurs et les caractéristiques du développement des activités autoérotiques, quel que soit le contexte culturel. Pour réaliser cette modélisation, les données neurobiologiques, ethologiques, ethnologiques et cliniques disponibles ont été comparées et synthétisées. On observe qu’apparemment le développement autoérotique dépend principalement des apprentissages provoqués par les stimulations des zones érogènes primaires. Mais ce développement est fortement influencé par les normes culturelles, qui peuvent être éducatives, permissives, restrictives ou répressives. En fonction du contexte culturel, le développement autoérotique peut débuter dès la première année après la naissance, ou être retardé, voire supprimé. En l’absence d’études détaillées tant en neurobiologie du développement que sur des échantillons représentatifs des différents contextes culturels, il est difficile de décrire précisément les phases et les époques du développement de l’autoérotisme. En simplifiant, le développement autoérotique le plus spontané correspondrait à celui décrit dans les contextes permissifs. On observe dans ces contextes que la plupart des garçons commencent à jouer avec leurs organes génitaux vers 6 ou 7 mois, les filles commencent à 10 ou 11 mois. En général, la masturbation – c’est-à-dire une activité intentionnelle et technique (en particulier des mouvements rythmiques…) de recherche du plaisir sexuel – n’est pas observée avant la deuxième ou la troisième année après la naissance. Le plus souvent elle commence à se développer entre le 15e et le 19e mois. Durant la masturbation, les signes de l’excitation incluent des poussées rythmiques du bassin, des sons, des rougeurs au visage et une respiration rapide. Les études déclaratives suggèrent l’existence de sensations érotiques et de type orgastique dès les premières années de la vie. Les activités autoérotiques coexistent avec les activités sexuelles avec des partenaires, mais ces dernières sont généralement préférées. Au fur et à mesure du développement et de l’accumulation des expériences autoérotiques et sexuelles, les activités autoérotiques deviennent plus cognitives et dépendent davantage de l’imagerie érotique. Elles peuvent également être associées à des émotions positives ou aversives, comme la culpabilité, ce qui peut induire des troubles. Fait notable en Occident, en raison des restrictions culturelles à la sexualité entre enfants, les activités autoérotiques apparaissent comme le principal moyen initial du développement sexuel.
... Tout particulièrement, il existe très peu de recherches sur la sexualité purement érotique, c'est-à-dire sur la neurobiologie des zones érogènes et surtout des zones érogènes non génitales. Pourtant, c'est apparemment une spécificité des hominidés : on observe que plusieurs zones du corps, même sans aucun rapport avec la reproduction, peuvent devenir érogènes (Turnbull et al., 2013 ; Wunsch, 2007). Mais comme on ne connaît pas les processus neurobiologiques à l'origine de cette érogénéisation du corps, il est donc très difficile de faire des recherches concernant l'influence des processus cognitifs sur ces processus de l'érogénéisation. ...
Article
L’objectif de cet article est d’identifier, chez les mammifères et l’être humain, les processus neurobiologiques de l’orientation sexuelle et de la formation des préférences sexuelles, puis d’évaluer leur importance respective. Les données ont été recueillies à partir d’une revue de la littérature qui concerne la neurobiologie de l’orientation et des préférences sexuelles. Chez les mammifères non primates (rongeurs, canidés, félidés, bovidés, équidés…), il existe différents types de processus et de situations à l’origine de la formation de préférences pour certains partenaires. Il existe également des processus neurobiologiques qui sont spécifiquement organisés pour l’orientation hétérosexuelle, et qui seraient, principalement, les circuits olfactifs qui détectent et traitent les phéromones sexuelles. Mais chez les hominidés (orangs-outans, gorilles, chimpanzés, bonobos, humains), les gènes des récepteurs aux phéromones sont altérés, diminuant ainsi l’importance fonctionnelle de ces processus de l’orientation sexuelle. Par contre, les processus à l’origine des préférences sexuelles deviennent plus importants. Pour ces raisons, chez l’être humain, les processus olfactifs altérés et les phéromones sexuelles n’auraient plus qu’une influence secondaire, et seraient combinés avec plusieurs autres facteurs (gènes, hormones, conditionnements, préférences sexuelles, émotions, processus cognitifs, contexte culturel). L’importance relative de chacun de ces facteurs dépendrait à la fois de caractéristiques physiologiques individuelles, du vécu singulier et des caractéristiques du contexte socioculturel. Cette combinaison complexe de plusieurs facteurs en interactions (incluant l’activité résiduelle des processus olfactifs de l’orientation sexuelle) serait à l’origine du développement de préférences sexuelles, propres à chaque personne.
... As Ross and Young (2009) proposed, sex through the ventro-ventral copulatory posture recapitulates parturition and nursing by maximizing the release of oxytocin. This is because the patterns of intimacy occurring during the missionary position such as eye contact contact, nipple stimulation, kissing, and ventro-ventral contact are associated with a release of oxytocin (Light, Grewen, & Amico, 2005;Komisaruk & Whipple, 2011;Turnbull, Lovett, Chaldecott, & Lucas, 2014;Castleman, 2015). As Larry Young and Brian Alexander summarized: ...
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Music is a remarkable universal human-unique trait based on a special genetic and neuroanatomical infrastructure, shared among vocal learners, that links auditory inputs to motor outputs via a sensorimotor feedback. This neural configuration is necessary for rhythmic synchronization, a crucial feature of music that fosters affiliation and positive affects. As a social glue, music is associated with an increased oxytocin and reduced testosterone and cortisol, an endocrine profile linked to parental care. Based on the physiological oxytocinergic loop extended to sociality, music is grounded on cooperation and affiliation. Hence, its power. Yet, how did music propagate? Sexual selection is a prominent theory, claiming that music evolved as an honest signal of cognitive, motor, and cooperative skills, thus an index of good genes positively valued by females. To empirically test sexual selection, and a possible musical division of labor, an experiment was run. The hypothesis was based on the evidence that a) the basal ganglia is a pivotal brain structure in rhythm synchronization which contains vasopressin (AVP) receptors; b) AVP is a neuropeptide similar to oxytocin abundant in males and related to music, dance, and courtship phenotypes; c) AVP peaks in women during ovulation, the most fertile period of the menstrual cycle, in which courtship receptivity reaches the maximum point. Fifteen subjects (8 men, 7 women) participated in a study that measured rhythmic skills through a tapping task. It was predicted that rhythmic synchronization is better in men than women, who perform at the best during ovulation. The hypothesis was confirmed: best synchronization and less tapping variability was recorded for men while within women, ovulation enhanced synchronization. Results point toward within- and between-sex differences in the core structure of music, rhythm, and highlight two aspects of the sexual selection theory: a) within-sex differences suggest that synchronization is a means for alignment during courtship displays; b) between-sex differences shed light on how cooperation and trust propagated. In courtship displays, synchronization is a partner test to assess compatibility. Coordinating in joint activities increases affiliation and positive feelings. By music, cooperation and trust spread in the human lineage via a selection against aggression, viz., neoteny. By reiteration, this inevitably led to a reduced sexual dimorphism and increased paternal care in our lineage, which are associated with reduced testosterone and increased oxytocin, the endocrine responses to music. In conclusion, through the extension of the oxytocin loop from physiology to the social realm, music extended trust and cooperation from blood relationships to peer relationships, allowing the emergence of a novel courtship display based on a cooperative competition.
... Of all human skin sites, the external genitalia are considered the areas with the highest potential for tactile pleasure 1 . This observation may be seen as an expression of the essential function of genitalia in procreation, more specifically the strong tie between sexual activity and reward 2 . ...
Article
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Current understanding of human genital-brain interactions relates primarily to neuroendocrine and autonomic control, whereas interactions during sexual stimulation remain largely unexplored. Here we present a systematic approach towards identifying how the human brain encodes sensory genital information. Using a validated affective touch paradigm and functional magnetic resonance imaging, we found that hedonic responses to discriminatory versus affective tactile stimulation were distinctly different for both penile shaft and forearm. This suggests that, as with other body sites, genital skin contains small diameter mechanoreceptive nerve fibres that signal pleasant touch. In the brain, secondary somatosensory cortex (S2) distinguished between affective and discriminative touch for the penile shaft, but not for the forearm. Frenulum stimulation induced the greatest reports of subjective pleasure and led to the greatest deactivation of the default-mode network. This study represents a first pass at investigating, in humans, the relationship between innervation of genital surfaces, hedonic feelings, and brain mechanisms, in a systematic way.
... Dit is in strijd met de gekende "Homunculus" vermits de dichtheid van sensorische vezels op de hand hoger is dan op het been (Pogliano, 2012). Deze inconsistentie is mogelijks te wijten aan het feit dat de binnenkant van het bovenbeen een belangrijke erogene zone is bij zowel mannen als vrouwen (Turnbull, Lovett, Chaldecott, & Lucas, 2014). ...
Thesis
Om de respons op tactiele stimuli te meten kunnen verschillende objectieve en subjectieve meetmethodes gehanteerd worden. Tot op heden worden vaak verbale responsen en vragenlijsten gebruikt.Het doel van deze exploratieve studie is om enerzijds na te gaan welke tactiele stimuli er best toegepast worden en anderzijds om de overeenkomsten tussen objectieve en subjectieve methodes in kaart te brengen om de respons op tactiele stimuli te meten.
... De manière concomitante au développement des activités de stimulation des zones érogènes, on observe que peut se développer une érogénéisation du corps : en plus des zones érogènes primaires, plusieurs régions corporelles -même si elles n'ont pas de relation avec la reproduction -peuvent devenir érogènes. Les zones potentiellement les plus érogènes sont les zones érogènes primaires (pénis et clitoris), la zone génitale, la zone orale, la zone anale, et, pour les femmes, les seins (Turnbull et al., 2013 ;Wunsch, 2007). Mais actuellement on connaît mal les caractéristiques neurobiologiques qui permettent à certaines régions du corps, autres que les zones érogènes primaires, de devenir érogène. ...
Article
L’objectif de cet article (en deux parties) est de présenter une modélisation du développement de la sexualité humaine, qui tienne compte à la fois de la biologie de la reproduction, de l’importance des affects et de la cognition, et de la diversité culturelle. Cette modélisation est réalisée à partir d’une synthèse transdisciplinaire de données provenant des neurosciences, de l’éthologie, l’ethnologie, l’histoire, et la psychologie. Au niveau biologique, le développement de la sexualité humaine se réaliserait à trois niveaux relativement indépendants : (1) le développement de la physiologie du système reproducteur (gamétogenèse, puberté, ménopause…), relativement indépendant des influences culturelles ; (2) le développement de l’érogénéisation du corps et des activités érotiques, dissocié des cycles hormonaux de la reproduction, mais fortement influencé par le contexte culturel ; et (3) le développement des représentations conceptuelles de la sexualité, non indispensables et parfois sans correspondance avec la réalité, mais qui peuvent exercer une influence majeure sur le développement sexuel. Spontanément, la sexualité se développerait dès les premières années de la vie, par observation, imitation, jeux sexuels, et apprentissages des activités tant autoérotiques qu’avec les pairs. Cette sexualité serait surtout centrée sur les zones érogènes primaires, et tendrait à devenir à l’âge adulte une caractéristique importante de la vie quotidienne. Mais les facteurs cognitifs et culturels seraient à l’origine d’une grande variabilité de ce développement, à la fois au niveau des comportements et des attitudes, mais surtout au niveau des représentations cognitives et des pratiques sociales.
... It is accepted that the clitoris is one of the most densely innervated organs in the female body and its only known purpose is to create sexual arousal when stimulated. In numerous studies (Schober et al., 2004;Ladas et al., 2005;Waskul et al., 2007;Turnbull et al., 2013), the clitoris is named by females as the most sensitive area of their genitalia and gives the strongest orgasms and greatest sexual pleasure, while the vagina, in this context, scores lower (Bronselaer et al., 2013). ...
Article
This review deals critically with many aspects of the functional genital anatomy of the human female in relation to inducing sexual arousal and its relevance to procreation and recreation. Various controversial problems are discussed including: the roles of clitorally versus coitally induced arousal and orgasm in relation to the health of women, the various sites of induction of orgasm and the difficulty women find in specifically identifying them because of “'ambiguity problems” and “genital site pareidolia,” the cervix and sexual arousal, why there are so many sites for arousal, why multiple orgasms occur, genital reflexes and coitus, the sites of arousal and their representation in the brain, and identifying aspects and functions of the genitalia with appropriate new nomenclature. Clin. Anat., 2014. © 2014 Wiley Periodicals, Inc.
... De surcroît, on observe également une évolution des zones érogènes : plusieurs régions du corps humain, non génitales, peuvent devenir érogènes (Turnbull et al., 2013 ;Wunsch, 2007). Le système pileux, qui joue un rôle social chez les mammifères (Morrison et al., 2010), peut chez l'humain transmettre des sensations érotiques (Jonsson et al., 2015). ...
Article
L’objectif de cet article est d’identifier précisément les facteurs à l’origine de l’évolution de la sexualité humaine. Les analyses présentées concernent principalement l’évolution des facteurs, proximaux, qui contrôlent la copulation hétérosexuelle prototypique des mammifères. Les données ont été recueillies à partir d’une revue de la littérature qui concerne l’évolution des facteurs neurobiologiques du comportement sexuel mammalien. Plusieurs études, en biologie, en génétique et en neurosciences, ont mis en évidence que certains de ces facteurs sont modifiés ou altérés au cours de l’évolution. Chez les primates, les circuits olfactifs sont altérés, les activités sexuelles se dissocient des cycles hormonaux (la reproduction et le comportement sexuel deviennent indépendants), le réflexe copulatoire de la lordose n’est plus fonctionnel, et le développement du cortex est majeur chez l’être humain. Pour ces raisons, l’analyse des données disponibles suggère que : (1) la dynamique du comportement sexuel a significativement évolué à partir des primates anthropoïdes ; (2) la dynamique fonctionnelle de la copulation hétérosexuelle est très probablement désorganisée ; (3) la dynamique comportementale qui émerge chez les hominidés – à partir des facteurs encore existants de la copulation hétérosexuelle – correspond vraisemblablement à une dynamique de recherche des récompenses érotiques, au moyen de la stimulation des zones érogènes ; et (4) chez l’être humain, en raison du développement majeur de la cognition, la sexualité est structurée par les représentations culturelles.
... There has also been an observed evolution in erogenous zones: several regions of the human body, not including the genitals, can become erogenous (Turnbull et al., 2013;Wunsch, 2007). The body hair, which plays a social role in mammals (Morrison et al., 2010), can transmit erotic sensations in humans (Jonsson et al., 2015). ...
Article
The aim of this article is to make a precise identification of the factors involved in the evolution of human sexuality. The analyses presented concern mainly the evolution of proximal factors that govern prototypical heterosexual copulation in mammals. The data was collected from a review of the literature concerning the evolution of neurobiological factors of sexual behaviour in mammals. Several studies, in biology, genetics and neurosciences, have shown that some of these factors have changed over the course of evolution. In primates, the olfactory circuits are impaired, sexual activities are dissociated from hormone cycles (reproduction and sexual behavior have become independent one from the other), the lordotic mating reflex is no longer functional and the cortex is highly developed in human beings. For these reasons, the analysis of available data suggests that: (1) the dynamics of sexual behaviour has significantly evolved from the anthropoid primates; (2) the functional dynamic of heterosexual copulation is very probably disorganized; (3) the behavioural dynamics that emerge with the hominidae – from factors that still exist in heterosexual copulation – would seem to be based on a quest for erotic reward, by stimulation of the erogenous zones; and (4) in humans, due to the extensive cognitive development, sexuality is structured by cultural representations.
... Tout particulièrement, il existe très peu de recherches sur la sexualité purement érotique, c'est-à-dire sur la neurobiologie des zones érogènes et surtout des zones érogènes non génitales. Pourtant, c'est apparemment une spécificité des hominidés : on observe que plusieurs zones du corps, même sans aucun rapport avec la reproduction, peuvent devenir érogènes (Turnbull et al., 2013 ;Wunsch, 2007). Mais comme on ne connaît pas les processus neurobiologiques à l'origine de cette érogénéisation du corps, il est donc très difficile de faire des recherches concernant l'influence des processus cognitifs sur ces processus de l'érogénéisation. ...
Article
Les recherches en neurosciences, dans le domaine de la sexualité (au sens large), étudient principalement des thèmes cliniques ou les processus neurobiologiques de la reproduction. Même en neurosciences cognitives, le rôle et l’importance de la cognition sur la sexualité est un thème généralement peu étudié. L’objectif de cet article est d’évaluer l’influence des processus cognitifs sur la sexualité, et en particulier sur l’activité des circuits cérébraux du comportement sexuel. Les données ont été recueillies à partir d’une revue de la littérature concernant les effets des processus cognitifs sur les structures neurobiologiques qui contrôlent le comportement sexuel. On observe que les processus cognitifs influencent la sexualité, de manière directe et indirecte, à deux niveaux distincts : cérébral et culturel. D’une part, les processus cognitifs participent à la création de techniques et à l’élaboration de symboles, de normes et de valeurs, qui sont à l’origine d’organisations sociales et culturelles particulières ; puis ces contextes socioculturels peuvent ensuite rétroagir sur les représentations cognitives, mais surtout influencer et structurer la sexualité (conceptualisation de 2 ou 3, voire 5 genres ; absence ou existence du baiser ; création de contraception et de procréation artificielle, qui dissocient reproduction et comportements hédoniques…). D’autre part, les représentations cognitives peuvent directement modifier l’activité des circuits sexuels : perceptions sensorielles, excitation sexuelle, système de récompense… ce qui influence les apprentissages et les comportements sexuels. En conclusion, les effets–indirects (via la culture) et directs – de la cognition sur la sexualité humaine apparaissent comme majeurs et structurants. Pour cette raison, il serait souhaitable de développer ce thème de recherche, afin de mieux évaluer et comprendre tant le rôle que l’importance des différents processus cognitifs sur les apprentissages sexuels et la sexualité.
... We studied eye fixations effects by means of the contrast between the areas of interest located in the genitals and faces. It is conceivable that the posterior insula, which is positioned close to the precentral and postcentral gyrus, receiving visual information from the striate and extrastriate cortices, can promote an embodied representation of genital feelings during VSS 18,[45][46][47] . That is, the posterior insula may extract sexually relevant information, coupled with the visual cortices, and helps to create an embodied representation, promoting empathy between the actor and the participant. ...
Article
Abstract Several studies highlighted the role of insula on several functions and in sexual behavior. This exploratory study examines the relationships among genital responses, brain responses, and eye movements, to disentangle the role played by the anterior and posterior insula during different stages of male sexual response and during visual attention to sexual stimuli. In 19 healthy men, fMRI, eye movement, and penile tumescence data were collected during a visual sexual stimulation task. After a whole-brain analysis comparing neutral and sexual clips and confirming a role for the bilateral insulae, we selected two bilateral seed regions in anterior and posterior insula for functional connectivity analysis. Single-ROI-GLMs were run for the FC target regions. Single-ROI-GLMs were performed based on areas to which participants fixate: “Faces”, “Genitals,” and “Background” with the contrast “Genitals > Faces”. Single-ROI-GLMs with baseline, onset, and sustained PT response for the sexual clips were performed. We found stronger effects for the posterior than the anterior insula. In the target regions of the posterior insula, we found three different pathways: the first involved in visual attention, onset of erection, and sustained erection; the second involved only in the onset of erection, and the third limited to sustained erection.
... Ramachandran suggested a neuroscientific explanation for the distribution of erogenous zones, based on the arrangement of body parts (such as the adjacent positioning of the genitals and the feet) in the primary somatosensory cortex (S1) [43]. A recent study [44] showed that the origins of erogenous distribution may be derived from a map located elsewhere in the brain. In this systematic survey of the magnitude of erotic sensations from various body parts of 800 participants, there was a very interesting demonstration that there were remarkable levels of correlation between ratings of intensity, regardless of the age, sexual orientation, nationality, race and sex of the sample. ...
Article
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Breasts, including the nipple and areola, have two functions: lactation and as an erogenous area. Male breasts are much less studied that those of women. In men, breasts have only an erotic function. Because there is dense and very well organized innervation of the nipple-areola complex in men, nipple erection occurs frequently and via different mechanisms from penile erection. Although it seems to be less important for men than for women and it is poorly studied, the erotic value of breast stimulation is notable. Consequently, there is a need to include this aspect in sexological and andrological studies and to preserve breasts and their innervation or to reconstruct them in cases of surgical intervention.
... This may be especially so in the case of orgasm. Although direct stimulation of the somatosensory cortex (and other areas of the brain) has produced a variety of sensations at correlative sites in the peripheral body, no similar direct brain stimulation thus far has produced erogenous sensation (Turnbull et al., 2014). This suggests but does not ascertain that orgasm is not epiphenomenal. ...
Article
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This article investigates transgender men’s phantom penis experience with respect to several contexts: historical reportage and medical explanations of phantom limbs and phantom penises following amputation; body dysphoria and “melancholic strength”; all renditions of trans penis including the testosterone-morphed clitoris; phenomenology and prosthetic incorporation; the neurobiology of metoidioplasty and phalloplasty; and neuroscience research on cortical mapping, hard-wired gender, proprioception, brain plasticity, epiphenomenal orgasm, the rubber hand illusion (RHI), virtual reality (VR) embodiment, and mirror neurons. Although a unique phantom instantiation, trans men’s phantom penises are instructively related to congenital aplasia, visual and motor neural simulation, and cis men’s phantom penises. I examine three aspects of trans men’s phantom penis: phantom presence of a penis, phantom penile erogenous sensation, and the volitional phantom penis. An emphasis on function over visibility, pleasure over presence, and synthesis over staidness enables an understanding of phantom penis sensation as the neurological underpinning of all erogenous penile perception and therefore a desirable asset for trans men’s sexuality. In that vein, cognitive imagination is deployed to postulate volitional phantom penises.
... The female body's erogenous zones are diverse, and appropriate stimulation and sexual excitement can trigger sexual arousal. These are the lips, back, neck, ears, forearm, breast and nipples 4 , mons veneris, the inside of the thigh, buttocks, anus, and abdomen; the most sensitive structures are the genitals 5 . In these places, stimulation can be performed in the form of manual stimulation and/or stimulation using the tongue or implements, such as vibrator, dildo, and other mechanical instruments. ...
Article
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Background: Female sexual function comprises variable and multi-layered conditions that incorporate complex interactions of physiological, psychological, and interpersonal components. Despite the progress in understanding the neurobiology of sexual response, the definition of normal sexual response in women remains unresolved. Normal female sexual function differs from individual to individual and depends on the culture, ideology, beliefs, and other factors. Methods: We used a case report, the purpose of which is to justify further investigation into the effectiveness of hypnosis for the treatment of cervical pain during penetration, as well as orgasm disorder. Results: An orgasm was reached by masturbation performed on her by her partner, but without an orgasm by penile-vaginal penetration. The frequency of sexual intercourse has increased (3-4 times/week) in comparison to prior to therapy (once/ 2 months). Orgasm does not occur by self-and by partner masturbation every time, but sporadically; however, more frequently than before therapy. Success has been achieved with the orgasm by penile-vaginal penetration. Conclusions: Hypnotherapy may be a promising co-intervention or intervention per se for both physical and psychological symptoms. The results of hypnotherapy demonstrate that symptoms were significantly alleviated and, consequently, the quality of life improved. Symptoms of pain during sexual intercourse were not eliminated, but the patient had achieved significant control over those symptoms.
... Many sites on the female body can evoke arousal when caressed-for example, the lips, nape and back of neck, ears, underarms, breasts and nipples, 12,13 pubic hairline, inside of thighs, buttocks, anus, and perineum-but the most sensitive structures lie in and around the genitalia. 14 The sites can be stimulated by different means (vibrators, dildoes, digitally, and lingually) and by PVI. One major difference of PVI from the other stimulations is that it is uniquely a multisite stimulus capable of activating some of-or all-the sites listed in Table 1. ...
Article
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The article consists of 6 sections written by separate authors that review female genital anatomy, the physiology of female sexual function and the pathophysiology of female sexual dysfunction but excluding hormonal aspects. Aim. To review female sexual function - physiology and pathophysiology- especially since 2010 and to make specific recommendations with levels of evidence ( Oxford Centre) where relevant. Conclusion. Despite numerous lab assesssments of female sexual function, genital assessments alone appear insufficient to characterise fully the complete sexual response.
... erotic zone, erotic spots itn.), ki ob ustreznem draženju in spolnem vznemirjenju sprožijo spolno vzburjenje. V grobem lahko te cone navedemo: ustnice, hrbet, zadnja stran vratu, ušesa, podlaket, prsi in bradavičke (Levin, Meston, 2006), mons veneris, notranjost stegna, zadnjica, anus in presredek, najobčutljivejše strukture v tej okolici pa so genitalije (Turnbull et al., 2014). Na naštetih mestih se lahko izvaja stimulacija v obliki ročne stimulacije in/ali stimulacije s pomočjo jezika ali pripomočkov, kot so: vibrator, dildo in drugi mehanični instrumenti. ...
... Many sites on the female body can evoke arousal when caressed-for example, the lips, nape and back of neck, ears, underarms, breasts and nipples, 12,13 pubic hairline, inside of thighs, buttocks, anus, and perineum-but the most sensitive structures lie in and around the genitalia. 14 The sites can be stimulated by different means (vibrators, dildoes, digitally, and lingually) and by PVI. One major difference of PVI from the other stimulations is that it is uniquely a multisite stimulus capable of activating some of-or all-the sites listed in Table 1. ...
Chapter
The human female orgasm bestows the greatest pleasure without recourse to drugs. Despite numerous studies there are many aspects of the activity that are poorly understood. These include its neurophysiology and pharmacology, while even its typology, induction, and function(s) are contentious issues. It can be induced by a variety of agencies that include genital and non-genital sites and even by exercise. While there are similarities with the male orgasm, there are a few differences, the major one being that women can have repeated multiple orgasms while males cannot. Despite recurrent speculative claims in the literature, it does not mediate or facilitate sperm transport through its uterine contractions. Brain imaging that measures cerebral regional blood flow has revealed that there is no single orgasm center, but rather specific areas are either activated, inhibited, or unaffected during orgasm. However, no consensus has yet been achieved due to experimental procedural differences and data handling by researchers.
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The study of emotional changes after brain injury has contributed enormously to the understanding of the neural basis of emotion. However, little attention has been placed on the methods used to elicit emotional responses in people with brain damage. Of particular interest are subjects with right hemisphere [RH] cortical lesions, who have been described as presenting impairment in emotional processing. In this article, an internal and external mood induction procedure [MIP] was used to trigger positive and negative emotions, in a sample of 10 participants with RH damage, and 15 healthy controls. Emotional experience was registered by using a self-report questionnaire. As observed in previous studies, internal and external MIPs were equally effective in eliciting the target emotion, but the internal procedure generated higher levels of intensity. Remarkably, participants with RH lesions were equally able to experience both positive and negative affect. The results are discussed in relation to the role of the RH in the capacity to experience negative emotions.
Article
Neuroanatomical textbooks typically restrict the central nervous system control of sexual responsiveness to the hypothalamus, brainstem and spinal cord. However, for all its primitive functions human sex is surprisingly complex and versatile. This review aims to extend the neuroanatomy of sexual responsiveness by providing a comprehensive overview of the empirical evidence for cerebral cortical involvement. To this end I will structure relevant human brain research data to fit the sexual pleasure cycle template-wanting sex, having sex, inhibiting sex-arguing that going through these sexual response phases requires adequate shifting between functional cortical networks. The relevance of this notion for understanding certain sexual dysfunctions is discussed. Clin. Anat., 2015. © 2015 Wiley Periodicals, Inc. © 2015 Wiley Periodicals, Inc.
Article
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The article consist of six sections written by separate authors that review female genital anatomy, the physiology of female sexual function, the pathophysiology of female sexual dysfunction but excluding hormonal aspects. Aim: To review the physiology of female sexual function and the pathophysiology of female sexual dysfunction especially since 2010 and to make specific recommendations accordng to the Oxford Centre for evidence based medicine (2009) "levels of evidence" wherever relevant. Conclusion: Recommendations were made for particular studies to be undertaken especially in controversial aspects in all six sections of the reviewed topics. Despite numerous laboratory assessments of female sexual function, genital assessments alone appear insufficient to characterise fully the complete sexual response.
Article
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Introduction: The projection of the human male urogenital system onto the paracentral lobule has not previously been mapped comprehensively. Aim: To map specific urogenital structures onto the primary somatosensory cortex toward a better understanding of sexual response in men. Methods: Using functional magnetic resonance imaging, we mapped primary somatosensory cortical responses to self-stimulation of the penis shaft, glans, testicles, scrotum, rectum, urethra, prostate, perineum, and nipple. We further compared neural response with erotic and prosaic touch of the penile shaft. Main outcome measure: We identified the primary mapping site of urogenital structures on the paracentral lobule and identified networks involved in perceiving touch as erotic. Results: We mapped sites on the primary somatosensory cortex to which components of the urogenital structures project in men. Evidence is provided that penile cutaneous projection is different from deep penile projection. Similar to a prior report in women, we show that the nipple projects to the same somatosensory cortical region as the genitals. Evidence of differential representation of erotic and nonerotic genital self-stimulation is also provided, the former activating sensory networks other than the primary sensory cortex, indicating a role of "top-down" activity in erotic response. Clinical implications: We map primary sites of projection of urogenital structures to the primary somatosensory cortex and differentiate cortical sites of erotic from nonerotic genital self-stimulation. Strength & limitations: To our knowledge, this is the first comprehensive mapping onto the primary somatosensory cortex of the projection of the components of the urogenital system in men and the difference in cortical activation in response to erotic vs nonerotic self-stimulation. The nipple was found to project to the same cortical region as the genitals. Evidence is provided that superficial and deep penile stimulation project differentially to the cortex, suggesting that sensory innervation of the penis is provided by more than the (pudendal) dorsal nerve. Conclusion: This study reconciles prior apparently conflicting findings and offers a comprehensive mapping of male genital components to the paracentral lobule. We provide evidence of differential projection of light touch vs pressure applied to the penile shaft, suggesting differential innervation of its superficial, vs deep structure. Similar to the response in women, we found nipple projection to genital areas of the paracentral lobule. We also provide evidence of differential representation of erotic and nonerotic genital self-stimulation, the former activating sensory networks other than the primary sensory cortex, indicating a role of top-down activity in erotic response. Allen K, Wise N, Frangos E, et al. Male Urogenital System Mapped Onto the Sensory Cortex: Functional Magnetic Resonance Imaging Evidence. J Sex Med 2020;XX:XXX-XXX.
Article
Introduction The article consists of six sections written by separate authors that review female genital anatomy, the physiology of female sexual function, and the pathophysiology of female sexual dysfunction but excluding hormonal aspects. Aim To review the physiology of female sexual function and the pathophysiology of female sexual dysfunction especially since 2010 and to make specific recommendations according to the Oxford Centre for evidence based medicine (2009) “levels of evidence” wherever relevant. Conclusion Recommendations were made for particular studies to be undertaken especially in controversial aspects in all six sections of the reviewed topics. Despite numerous laboratory assessments of female sexual function, genital assessments alone appear insufficient to characterise fully the complete sexual response.
Chapter
The fusion of the male and female gamete is usually preceded by intense interpersonal touch, especially involving stimulation of parts of the genital tract. However, the effects of sexual genital stimulation reach beyond fertilization and reproduction, as shown by experimental evidence that the pleasure drawn from it drives sexual desire, mediates the formation of sexual preferences, and improves general well-being. The brain processes sexual stimuli like other pleasurable stimuli, which means that they go through a cycle where they are identified, desired, consumed, and devalued. Genital receptors and nerve fibers may thus primarily serve a proximal master—pleasure. In this chapter, we outline what is known about the peripheral and central processes involved in the perception of pleasurable sexual touch and intimacy. As sexual behavior is typically social (i.e., involves human stimuli), genital afferent input might well adhere to the principles of the social touch system.
Article
Purpose: More early-staged breast cancer patients are choosing mastectomy. No studies have addressed breast-specific sensuality (BSS), defined as the breast's role during intimacy. We explored BSS among women undergoing lumpectomy (L), mastectomy alone (M), or with reconstruction (MR) and analyzed the association of surgical modality with sexual function. Methods: Women undergoing breast cancer surgery between 2000 and 2013 were eligible for survey using investigator-generated questions and the Female Sexual Function Index (FSFI). Demographic and surgical data were collected by chart review. The Kruskal-Wallis test was used to analyze FSFI scores, and χ (2) or Fisher's exact tests were used for categorical data. Results: Of 453 invited participants, 268 (59%) completed the survey. Of these, 69.4, 22.4, and 8.2% underwent L, MR, or M, respectively. The importance of the breast/chest wall during intimacy declined significantly regardless of surgical modality (L 83-74%, p = 0.0006; M 95-47%, p = 0.003; MR 93-77%, p = 0.002). No difference in sexual function was found between L, MR, and M (median FSFI score 28.2, 27.5, 25.9, respectively; p = 1.0). Comparing L versus MR, higher FSFI scores resulted with appearance satisfaction (29.0 vs. 22.6 p = 0.002) and preserved BSS as pleasurable breast caress (28.8 vs. 26.5, p = 0.04) and the breast as part of intimacy (28.8 vs. 24.8, p = 0.1). Conclusions: Breast cancer surgery is associated with lowered BSS. However, BSS and appearance satisfaction scores are better for L and appear to correlate with improved sexual function postoperatively. These data may guide surgical counseling and contribute to survivorship outcomes.
Article
This study hypothesized that the facial WHR of celebrity endorsers is associated with their endorsement income. Our sample consisted of the top 100 male and female celebrity endorsers (male = 50 and female = 50) in Seoul. The average annual total endorsement income of celebrity endorsers in 2012 was $1,691,924 for male endorsers and $1,684,474 for female endorsers. A statistical analysis demonstrated a significant negative correlation between celebrity endorsers’ facial WHR and their endorsement income in 2012 among male (r = −.390, p = .007, n = 47) but not among female (r = .166, p = . 248, n = 50) endorsers. Our findings imply that males with narrower faces are more popular among the media as well as among advertisers. Our study is the first to explore the relationship between physical features, such as facial WHR and monetary income in the entertainment industry.
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Question the assumption that the adult brain is “hard wired” After amputation many people experience vivid sensations of the body part they have lost.1 These “sensory ghosts” can arise within hours of the loss of the limb and are often painful. Such phenomena have been a mysterious part of medical lore for over a century, but recent research suggests that phantoms can teach us substantial lessons about the organisation and plasticity of the brain. Fig 1. How amputees perceive their phantoms (Credit: ALEXA WRIGHT) We stand to learn most from phantoms if we attend closely to patients' subjective reports. One innovative study, for example, has made use of digital photography to depict how amputees perceive their phantoms (fig 1) (A Wright et al, Wellcome Trust Sci Art Project, 1997). By remaining true to patients' own experiences, the researchers found it …
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Introduction. The role of nipple/breast stimulation in influencing sexual arousal in men and women during lovemaking has only been the subject of opinion-based comment rather than evidence-based study. No attempt to question people about such sexual behavior has ever been undertaken. Aim. The study was designed to ascertain the effects of nipple/breast manipulation in young men and women on their sexual arousal. Methods. A short questionnaire about nipple/breast stimulation during sexual activity was administered to 301 (148 men; 153 women) sexually experienced undergraduates (age range 17–29 years, 95% between 18 and 22). Main Outcome Measures. Replies to questions in questionnaire. Results. The major findings in regard to the women were that 81.5% reported that stimulation of their nipples/breasts caused or enhanced their sexual arousal, 78.2% agreed that when sexually aroused such manipulation increased their arousal, 59.1% had asked to have their nipples stimulated during lovemaking, and only 7.2% found that the manipulation decreased their arousal. In regard to the men, 51.7% reported that nipple stimulation caused or enhanced their sexual arousal, 39% agreed that when sexually aroused such manipulation increased their arousal, only 17.1% had asked to have their nipples stimulated, and only 7.5% found that such stimulation decreased their arousal. Conclusion. Manipulation of the nipples/breasts causes or enhances sexual arousal in approximately 82% of young women and 52% of young men with only 7–8% reporting that it decreased their arousal. Levin R, and Meston C. Nipple/breast stimulation and sexual arousal in young men and women. J Sex Med 2006;3:450–454.
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Another person’s caress is one of the most powerful of all emotional social signals. How much the primary somatosensory cortices (SIs) participate in processing the pleasantness of such social touch remains unclear. Although ample empirical evidence supports the role of the insula in affective processing of touch, here we argue that SI might be more involved in affective processing than previously thought by showing that the response in SI to a sensual caress is modified by the perceived sex of the caresser. In a functional MRI study, we manipulated the perceived affective quality of a caress independently of the sensory properties at the skin: heterosexual males believed they were sensually caressed by either a man or woman, although the caress was in fact invariantly delivered by a female blind to condition type. Independent analyses showed that SI encoded, and was modulated by, the visual sex of the caress, and that this effect is unlikely to originate from the insula. This suggests that current models may underestimate the role played by SI in the affective processing of social touch.
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The representation of the body in the brain, the homunculus, was posited by Wilder Penfield based on his studies of patients with intractable epilepsy. While he mapped both male and female patients, Penfield reports little about the females. The now iconic illustration of the map is clearly male with testicles, penis, and no breasts. In order to bring attention to this omission and to stimulate studies of female somatosensory cortex (SS), we discuss what is known about the map of the female body in the brain, including Penfield's findings in his female patients and subsequent work by others exploring the human female SS. We reveal that there is much we do not know about how the entire female body is represented in the brain or how it might change with different reproductive life stages, hormones, and experiences. Understanding what is and is not currently known about the female SS is a first step toward fully understanding neurological and physiological sex differences, as well as producing better-informed treatments for pain conditions related to mastectomy, hysterectomy, vulvodynia, and fibromyalgia. We suggest that the time is ripe for a full mapping of the female brain with the production of a hermunculus.
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The projection of vagina, uterine cervix, and nipple to the sensory cortex in humans has not been reported. The aim of this study was to map the sensory cortical fields of the clitoris, vagina, cervix, and nipple, toward an elucidation of the neural systems underlying sexual response. Using functional magnetic resonance imaging (fMRI), we mapped sensory cortical responses to clitoral, vaginal, cervical, and nipple self-stimulation. For points of reference on the homunculus, we also mapped responses to the thumb and great toe (hallux) stimulation. The main outcome measures used for this study were the fMRI of brain regions activated by the various sensory stimuli. Clitoral, vaginal, and cervical self-stimulation activated differentiable sensory cortical regions, all clustered in the medial cortex (medial paracentral lobule). Nipple self-stimulation activated the genital sensory cortex (as well as the thoracic) region of the homuncular map. The genital sensory cortex, identified in the classical Penfield homunculus based on electrical stimulation of the brain only in men, was confirmed for the first time in the literature by the present study in women applying clitoral, vaginal, and cervical self-stimulation, and observing their regional brain responses using fMRI. Vaginal, clitoral, and cervical regions of activation were differentiable, consistent with innervation by different afferent nerves and different behavioral correlates. Activation of the genital sensory cortex by nipple self-stimulation was unexpected, but suggests a neurological basis for women's reports of its erotogenic quality.
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Polar bears (Ursus maritimus) are among those species most susceptible to the rapidly changing arctic climate, and their survival is of global concern. Despite this, little is known about polar bear species history. Future conservation strategies would significantly benefit from an understanding of basic evolutionary information, such as the timing and conditions of their initial divergence from brown bears (U. arctos) or their response to previous environmental change. We used a spatially explicit phylogeographic model to estimate the dynamics of 242 brown bear and polar bear matrilines sampled throughout the last 120,000 years and across their present and past geographic ranges. Our results show that the present distribution of these matrilines was shaped by a combination of regional stability and rapid, long-distance dispersal from ice-age refugia. In addition, hybridization between polar bears and brown bears may have occurred multiple times throughout the Late Pleistocene. The reconstructed matrilineal history of brown and polar bears has two striking features. First, it is punctuated by dramatic and discrete climate-driven dispersal events. Second, opportunistic mating between these two species as their ranges overlapped has left a strong genetic imprint. In particular, a likely genetic exchange with extinct Irish brown bears forms the origin of the modern polar bear matriline. This suggests that interspecific hybridization not only may be more common than previously considered but may be a mechanism by which species deal with marginal habitats during periods of environmental deterioration.
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The relationship between phantom limb phenomena and cortical reorganization was examined in five subjects with congenital absence of an upper limb and nine traumatic amputees. Neuromagnetic source imaging revealed minimal reorganization of primary somatosensory cortex in the congenital amputees (M=0.69 cm, SD 0.24) and the traumatic amputees without phantom limb pain (M=0.27 cm, SD 0.25); the amputees with phantom limb pain showed massive cortical reorganization (M=2.22 cm, SD 0.78). Phantom limb pain and nonpainful phantom limb phenomena were absent in the congenital amputees. Whereas phantom limb pain was positively related to cortical reorganization (r=0.87), nonpainful phantom phenomena were not significantly correlated with cortical reorganization (r=0.34). Sensory discrimination was normal and mislocalization (referral of stimulation-induced sensation to a phantom limb) was absent in the congenital amputees. The role of peripheral and central factors in the understanding of phantom limb pain and phantom limb phenomena is discussed in view of these findings.
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Damage to the right parietal lobe has long been associated with various disorders of body image. The authors have recently suggested that an unusual behavioural condition in which otherwise rational individuals desire the amputation of a healthy limb might also arise from right parietal dysfunction. Four subjects who desired the amputation of healthy legs (two right, one left and one, at first, bilateral and then left only) were recruited and underwent magnetoencephalography (MEG) scans during tactile stimulation of sites above and below the desired amputation line. Regions of interest (ROIs) in each hemisphere (superior parietal lobule (SPL), inferior parietal lobule, S1, M1, insula, premotor cortex and precuneus) were defined using FreeSurfer software. Analysis of average MEG activity across the 40-140 ms post-stimulation timeframe was carried out using an unpaired t test. This revealed significantly reduced activation only in the right SPL ROI for the subjects' affected legs when compared with both subjects' unaffected legs and that of controls. The right SPL is a cortical area that appears ideally placed to unify disparate sensory inputs to create a coherent sense of having a body. The authors propose that inadequate activation of the right SPL leads to the unnatural situation in which the sufferers can feel the limb in question being touched without it actually incorporating into their body image, with a resulting desire for amputation. The authors introduce the term 'xenomelia' as a more appropriate name than apotemnophilia or body integrity identity disorder, for what appears to be an unrecognised right parietal lobe syndrome.
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Evidence from a large number of brain imaging studies has shown that, in humans, the insula, and especially its anterior part, is involved in emotions and emotion recognition. Typically, however, these studies revealed that, besides the insula, a variety of other cortical and subcortical areas are also active. Brain imaging studies are correlative in nature, and, as such, they cannot give indications about the necessary contribution of the different centers involved in emotions. In the present study, we aimed to define more clearly the role of the insula in emotional and social behavior of the monkey by stimulating it electrically. Using this technique, one may determine whether direct activation of the insula can produce specific emotional or social behaviors and exactly which parts of this structure are responsible for these behaviors. The results showed that two emotional behaviors, a basic one (disgust) and a social one (affiliative state), were easily elicited by electrical stimulation of specific parts of the insula. Both behaviors were characterized by specific motor and vegetative responses and by a dramatic change in the monkey's responsiveness to external stimuli.
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CT (C tactile) afferents are a distinct type of unmyelinated, low-threshold mechanoreceptive units existing in the hairy but not glabrous skin of humans and other mammals. Evidence from patients lacking myelinated tactile afferents indicates that signaling in these fibers activate the insular cortex. Since this system is poor in encoding discriminative aspects of touch, but well-suited to encoding slow, gentle touch, CT fibers in hairy skin may be part of a system for processing pleasant and socially relevant aspects of touch. CT fiber activation may also have a role in pain inhibition. This review outlines the growing evidence for unique properties and pathways of CT afferents.
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Of 40 cases of bilateral orchiectomy, 9 (22.5 per cent) reported phantoms. Two right unilateral orchiectomies also resulted in phantoms. Of 6 cases reinterviewed, 3 continued not to perceive the phantom, 1 affirmed its continuation, and 2 perceived it who originally did not. The sensations of nonexistent testes were variously described as “natural,” “burning,” “hard,” etc.A major characteristic of phantoms of the genitalia, in contrast to those of skeletal parts, appears to be their marked relationship to chronological age.RésuméSur 40 cas d'orchiectomie bilatérale, 9 (22,5%) signalaient des fantômes. Aprés 2 orchiectomies unilatérales droites, des fantômes étaient également signalés. Sur les 6 cas qui purent être interrogés à nouveau, 3 ne percevaient plus de fantôme, l'un affirmait sa persistance, et 2 le percevaient alors qu'ils ne l'avaient pas originellement éprouvé. Les sensations de testicule absent étaient décrites de façon variée; “naturelles,” “brulantes,” “dures,” etc.... Une des caractéristiques majeures des fantômes des parties génitales, en opposition avec ceux des segments squelettiques paraît consister dans leur relation avec l'âge chronologique.ZusammenfassungBei 40 beidseits hodenoperierten Patienten traten 9mal Phantombildungen auf (22,5%). Ebenso wurde in 2 Fällen von rechts einseitiger Hodenentfernung eine Phantombildung beobachtet. 6 Kranke wurden nachexploriert. 3 von ihnen hatten ihr Phantomerlebnis verloren. In einem Fall bestand das Phantom weiter und in 2 Fällen hatten sich Phantom neu gezeigt, die ursprünglich fehlten. Die nicht existierenden Testes wurden verschiedenartig empfunden, z.B. als natüralich, brennend, drückend u.a.m.Im Gegensatz zu Gliedmassenphantomen schien es für die genitalen Phantombildungen besonders charakteristisch, dass sie in engerer Beziehung zum Levensalter standen.
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It is argued that developmental psychologists need attitudes, methods, and conceptual schemes that integrate the distinctive contributions of nature and nurture to study developmental change as well as consistency in both developmental functions and individual differences in behaviors of interest. A conceptual scheme for early mental development is described that synthesizes these disparate orientations. This theoretical viewpoint deals with 2 sets of seemingly contradictory facts: (1) the early portion of the developmental function is largely maturational, while individual differences are unstable and not highly correlated with either genetic or environmental factors; and (2) as nature's hold on the developmental function declines with age, individual differences correlate more strongly with both genetic and environmental factors.
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Reviews the book, Genes and behavior: Nature-nurture interplay explained by M. Rutter (see record 2006-01387-000). Surveying developments in behavior genetics, Michael Rutter provides an integrative synthesis in writing that is both important and timely. The book aims to offer a nontechnical account of the "various ways in which genetic influences on behavior may be important." To do so, Rutter reviews what is known of environmental influences and how genes and environments might work across development. The book is effectively organized. A first group of five chapters is devoted to quantifying the strength of genetic and environmental influences and illustrating study designs that do so. A second group of three chapters discusses specific genes known to influence behavior outcomes and offers a readable discussion of how such genes might actually work during behavioral development. Before a final summary, there are two provocative chapters; one discussing the role of GE interaction and correlation, and another focused on what environments can do to gene expression. This highly readable and largely nontechnical book provides the reader with insightful understanding of contemporary behavior genetic research. It deserves to be widely read. (PsycINFO Database Record (c) 2012 APA, all rights reserved)
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Children increasingly resemble their parents in cognitive abilities from infancy through adolescence. Results obtained from a 20-year longitudinal adoption study of 245 adopted children and their biological and adoptive parents, as well as 245 matched nonadoptive (control) parents and offspring, show that this increasing resemblance is due to genetic factors. Adopted children resemble their adoptive parents slightly in early childhood but not at all in middle childhood or adolescence. In contrast, during childhood and adolescence, adopted children become more like their biological parents, and to the same degree as children and parents in control families. Although these results were strongest for general cognitive ability and verbal ability, similar results were found for other specific cognitive abilities - spatial ability, speed of processing, and recognition memory. These findings indicate that, within this population, genes that stably affect cognitive abilities in adulthood do not all come into play until adolescence and that environmental factors that contribute to cognitive development are not correlated with parents' cognitive ability.
Article
Xenomelia is the oppressive feeling that one or more limbs of one's body do not belong to one's self. We present the results of a thorough examination of the characteristics of the disorder in 15 males with a strong desire for amputation of one or both legs. The feeling of estrangement had been present since early childhood and was limited to a precisely demarcated part of the leg in all individuals. Neurological status examination and neuropsychological testing were normal in all participants, and psychiatric evaluation ruled out the presence of a psychotic disorder. In 13 individuals and in 13 pair-matched control participants, magnetic resonance imaging was performed, and surface-based morphometry revealed significant group differences in cortical architecture. In the right hemisphere, participants with xenomelia showed reduced cortical thickness in the superior parietal lobule and reduced cortical surface area in the primary and secondary somatosensory cortices, in the inferior parietal lobule, as well as in the anterior insular cortex. A cluster of increased thickness was located in the central sulcus. In the left hemisphere, affected individuals evinced a larger cortical surface area in the inferior parietal lobule and secondary somatosensory cortex. Although of modest size, these structural correlates of xenomelia appear meaningful when discussed against the background of some key clinical features of the disorder. Thus, the predominantly right-sided cortical abnormalities are in line with a strong bias for left-sided limbs as the target of the amputation desire, evident both in our sample and in previously described populations with xenomelia. We also propose that the higher incidence of lower compared with upper limbs (∼80% according to previous investigations) may explain the erotic connotations typically associated with xenomelia, also in the present sample. These may have their roots in the proximity of primary somatosensory cortex for leg representation, whose surface area was reduced in the participants with xenomelia, with that of the genitals. Alternatively, the spatial adjacency of secondary somatosensory cortex for leg representation and the anterior insula, the latter known to mediate sexual arousal beyond that induced by direct tactile stimulation of the genital area, might play a role. Although the right hemisphere regions of significant neuroarchitectural correlates of xenomelia are part of a network reportedly subserving body ownership, it remains unclear whether the structural alterations are the cause or rather the consequence of the long-standing and pervasive mismatch between body and self.
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This book brings to date the reports and conclusions from the Montreal Neurological Institute's clinical, physiological, and neuro-surgical studies of epilepsy, and is, in a sense, a sequal to "Epilepsy and cerebral localization," published in 1941. There is extensive addition of new material on subcortical mechanisms, functional cortical localization, surgical and medical treatment and electroencephalography. The book is illustrated with 8 color plates and 314 black and white illustrations. (PsycINFO Database Record (c) 2012 APA, all rights reserved)
Article
Many clinical pain conditions, including migraine, fibromyalgia, and temporomandibular disorders, occur more frequently among females than males. Greater pain sensitivity among females has been considered as one possible explanation for these differences. Despite considerable clinical and experimental research on the topic, no consensus has emerged on the existence or nature of gender differences in response to noxious stimuli. In this Focus article the authors take the position that females exhibit greater sensitivity to noxious stimuli than males. In support of this position, they review the experimental literature on gender and pain responses. Then, they present and discuss a schematic model of several systems involved in the transmission and modulation of nociceptive information, which may contribute to gender-associated differences in pain sensitivity. Finally, the authors highlight several issues to be addressed by future research in this area.
Article
It has been convincingly established, over the past decade, that the human insular cortices are involved in processing both body feelings (such as pain) and feelings of emotion. Recently, however, an interpretation of this finding has emerged suggesting that the insular cortices are the necessary and sufficient platform for human feelings, in effect, the sole neural source of feeling experiences. In this study, we investigate this proposal in a patient whose insular cortices were destroyed bilaterally as a result of Herpes simplex encephalitis. The fact that all aspects of feeling were intact indicates that the proposal is problematic. The signals used to assemble the neural substrates of feelings hail from different sectors of the body and are conveyed by neural and humoral pathways to complex and topographically organized nuclei of the brain stem, prior to being conveyed again to cerebral cortices in the somatosensory, insular, and cingulate regions. We suggest that the neural substrate of feeling states is to be found first subcortically and then secondarily repeated at cortical level. The subcortical level would ensure basic feeling states while the cortical level would largely relate feeling states to cognitive processes such as decision-making and imagination.
Book
This book is based on the Lane Medical Lectures which Penfield gave in 1947. Four hundred craniotomies performed between 1928 and 1947 presented the opportunity to stimulate various parts of the cerebral cortex with electrical currents and to record the objective (movements) and subjective effects. The results of these studies are presented clearly and with the necessary details. Objective results and interpretation are sharply separated. The investigations give a very complete description of the organization of the sensorimotor cortex. The primitive character of the movements is emphasized. They are "not more complicated than those the newborn infant is able to perform." Evidence of the existence of a secondary motor cortex is also presented. A certain muscle may show widely separated cortical foci when it is used in different functional groupings. Central overlap exists clearly in precentral and postcentral gyrus. The authors assume that the diencephalon plays an important role in
Article
It has been clear for almost two decades that cortical representations in adult animals are not fixed entities, but rather, are dynamic and are continuously modified by experience. The cortex can preferentially allocate area to represent the particular peripheral input sources that are proportionally most used. Alterations in cortical representations appear to underlie learning tasks dependent on the use of the behaviorally important peripheral inputs that they represent. The rules governing this cortical representational plasticity following manipulations of inputs, including learning, are increasingly well understood. In parallel with developments in the field of cortical map plasticity, studies of synaptic plasticity have characterized specific elementary forms of plasticity, including associative long-term potentiation and long-term depression of excitatory postsynaptic potentials. Investigators have made many important strides toward understanding the molecular underpinnings of these fundamental plasticity processes and toward defining the learning rules that govern their induction. The fields of cortical synaptic plasticity and cortical map plasticity have been implicitly linked by the hypothesis that synaptic plasticity underlies cortical map reorganization. Recent experimental and theoretical work has provided increasingly stronger support for this hypothesis. The goal of the current paper is to review the fields of both synaptic and cortical map plasticity with an emphasis on the work that attempts to unite both fields. A second objective is to highlight the gaps in our understanding of synaptic and cellular mechanisms underlying cortical representational plasticity.
Article
An ascending sensory pathway that underlies feelings from the body, such as cooling or toothache, terminates in the posterior insula. Considerable evidence suggests that this activity is rerepresented and integrated first in the mid-insula and then in the anterior insula. Activation in the anterior insula correlates directly with subjective feelings from the body and, strikingly, with all emotional feelings. These findings appear to signify a posterior-to-anterior sequence of increasingly homeostatically efficient representations that integrate all salient neural activity, culminating in network nodes in the right and left anterior insulae that may be organized asymmetrically in an opponent fashion. The anterior insula has appropriate characteristics to support the proposal that it engenders a cinemascopic model of human awareness and subjectivity. This review presents the author's views regarding the principles of organization of this system and discusses a possible sequence for its evolution, as well as particular issues of historical interest.
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Across many species, males exhibit plastic responses when they encounter mating rivals. The ability to tailor responses to the presence of rivals allows males to increase investment in reproduction only when necessary. This is important given that reproduction imposes costs that limit male reproductive capacity, particularly when sperm competition occurs. Fruitfly (Drosophila melanogaster) males exposed to rivals subsequently mate for longer and thus accrue fitness benefits under increased competition, in line with theory. Here, we show that male D. melanogaster detect rivals by using a suite of cues and that the resulting responses lead directly to significant fitness benefits. We used multiple techniques to systematically remove auditory, olfactory, tactile, and visual cues, first singly and then in all possible combinations. No single cue alone was sufficient to allow males to detect rivals. However, the perception of any two cues from sound, smell, or touch permitted males to detect and respond adaptively to rivals through increased offspring production. Vision was only of marginal importance in this context. The findings indicate adaptive redundancy through the use of multiple, but interchangeable, cues. We reveal the robust mechanisms by which males assess their socio-sexual environment to precisely attune responses via the expression of plastic behavior.
Article
Animal behavior is governed by the activity of interconnected brain circuits. Comprehensive brain wiring maps are thus needed in order to formulate hypotheses about information flow and also to guide genetic manipulations aimed at understanding how genes and circuits orchestrate complex behaviors. To assemble this map, we deconstructed the adult Drosophila brain into approximately 16,000 single neurons and reconstructed them into a common standardized framework to produce a virtual fly brain. We have constructed a mesoscopic map and found that it consists of 41 local processing units (LPUs), six hubs, and 58 tracts covering the whole Drosophila brain. Despite individual local variation, the architecture of the Drosophila brain shows invariance for both the aggregation of local neurons (LNs) within specific LPUs and for the connectivity of projection neurons (PNs) between the same set of LPUs. An open-access image database, named FlyCircuit, has been constructed for online data archiving, mining, analysis, and three-dimensional visualization of all single neurons, brain-wide LPUs, their wiring diagrams, and neural tracts. We found that the Drosophila brain is assembled from families of multiple LPUs and their interconnections. This provides an essential first step in the analysis of information processing within and between neurons in a complete brain.
Article
Evidence from patients has shown that primary somatosensory representations are plastic, dynamically changing in response to central or peripheral alterations, as well as experience. Furthermore, recent research has also demonstrated that altering body posture results in changes in the perceived sensation and localization of tactile stimuli. Using evidence from behavioral studies with brain-damaged and healthy subjects, as well as functional imaging, we propose that the traditional concept of the body schema should be divided into three components. First are primary somatosensory representations, which are representations of the skin surface that are typically somatotopically organized, and have been shown to change dynamically due to peripheral (usage, amputation, deafferentation) or central (lesion) modifications. Second, we argue for a mapping from a primary somatosensory representation to a secondary representation of body size and shape (body form representation). Finally, we review evidence for a third set of representations that encodes limb position and is used to represent the location of tactile stimuli relative to the subject using external, non-somatotopic reference frames (postural representations).
Article
We studied the central representation of pudendal afferents arising from the clitoral nerves in 15 healthy adult female subjects using electrical dorsal clitoral nerve stimulation and fMRI. As a control body region, we electrically stimulated the right hallux in eight subjects. In a block design experiment, we applied bilateral clitoral stimulation and unilateral (right) hallux stimulation. Activation maps were calculated for the contrasts 'electrical dorsal clitoral nerve stimulation versus rest' and 'electrical hallux stimulation versus rest'. A random-effect group analysis for the clitoral stimulation showed significant activations bilateral in the superior and inferior frontal gyri, insulae and putamen and in the postcentral, precentral and inferior parietal gyri (including the primary and secondary somatosensory cortices). No activation was found on the mesial surface of the postcentral gyrus. For the hallux, activations occurred in a similar neuronal network but the activation in the primary somatosensory cortex was localized in the inter-hemispheric fissure. The results of this study demonstrate that the central representation of pudendal afferents arising from the clitoral nerves and sensory inputs from the hallux can be studied and distinguished from each other by fMRI. From the somatotopic order described in the somatosensory homunculus one would expect for electrical clitoral nerve stimulation activation of the mesial wall of the postcentral gyrus. In contrast, we found activations on the lateral surface of the postcentral gyrus.
Article
Biological differences in male and female sexuality are obvious in the behavioral domain, but the central mechanisms that might explain these behavioral gender differences remain unclear. In this study, we merged two earlier positron emission tomography data sets to enable systematic comparison of the brain responses in heterosexual men and women during sexual tactile genital (penile and clitoral) stimulation and during orgasm. Gender commonalities were most evident during orgasm, a phase which demonstrated activations in the anterior lobe of the cerebellar vermis and deep cerebellar nuclei, and deactivations in the left ventromedial and orbitofrontal cortex in both men and women. During tactile genital stimulation, deactivations in the right amygdala and left fusiform gyrus were found for both genders. Marked gender differences were seen during this phase: left fronto-parietal areas (motor cortices, somatosensory area 2 and posterior parietal cortex) were activated more in women, whereas in men, the right claustrum and ventral occipitotemporal cortex showed larger activation. The only prominent gender difference during orgasm was male-biased activation of the periaqueductal gray matter. From these results, we conclude that during the sexual act, differential brain responses across genders are principally related to the stimulatory (plateau) phase and not to the orgasmic phase itself. These results add to a better understanding of the neural underpinnings of human sexuality, which might benefit treatment of psychosexual disorders.
Article
The anterior insular cortex (AIC) is implicated in a wide range of conditions and behaviours, from bowel distension and orgasm, to cigarette craving and maternal love, to decision making and sudden insight. Its function in the re-representation of interoception offers one possible basis for its involvement in all subjective feelings. New findings suggest a fundamental role for the AIC (and the von Economo neurons it contains) in awareness, and thus it needs to be considered as a potential neural correlate of consciousness.
Article
A stratified organization of visual, somatic and acoustic representations was observed in the cat SC. Cells of the superficial laminae were exclusively visual. Visual, somatic, and acoustic cells were observed in the intermediate laminae while the deeper laminae were predominantly nonvisual. A detailed examination of the tactile representation revealed a somatotopic plan which was in register with the overlying visuotopy. The magnified representation of central visual fields overlapped the magnified tactile representation of the face and, as visual RFS moved temporally, the underlying tactile RFS were displaced caudal and distal. This topographical overlap can be recognized if the visual field is depicted as a flexible sheet which is stretched over the body with the area centralis superimposed on the nose and the limbs radiating out at an acute angle. The overlapping topographies and similarities in stimulus specificity of somatic and visual cells, as well as the similar behavioral deficits previously described following SC lesions, suggests a functional parallel between modalities in the SC. The possibility that visual, somatic, and acoustic cells converge on a common delivery or distribution system, which is located in the intermediate-deeper SC strata and organizes orienting and following responses on the basis of multimodality cues, is discussed.
Article
The topographic organization of the somatosensory representation in the deep layers of the cat superior colliculus was reexamined using methods previously used to examine the visuotopy in these layers. This technique identified the distribution of neurons in the superior colliculus that represent a designated region of the body surface (i.e., a dermal image), as well as assessed the differential distribution of deep layer neurons representing different body regions (e.g., face, forelimb, hindlimb, etc.). When the area of densest representation within a dermal image was considered, a well-ordered somatotopy was evident that was similar to the one previously described (Stein et al., '76: J. Neurophysiol. 39:401-419). Each region of the body surface, however, was represented within a surprisingly broad area of the deep layers, which often had considerable overlap with the representations of adjacent body regions. This organization was similar to that of the deep layer visuotopy and emphasizes that the representation of a peripheral stimulus is accomplished by the simultaneous activation of a large population of deep layer neurons. Furthermore, an examination of the convergence patterns on somatosensory-responsive neurons demonstrated that the somatotopy was formed primarily by multisensory neurons. These data indicate that the somatosensory representation is best considered as a component of a comprehensive multisensory functional unit that plays a critical role in effecting behavioral responses to a wide variety of stimuli.
Article
The somatosensory map of the superior colliculus was studied in the mouse during the 2nd and 3rd postnatal weeks, with particular attention to the representation of the vibrissae. The presence of an organized somatosensory projection was not electrophysiologically demonstrable until the beginning of the 3rd postnatal week, in coincidence with the opening of the eyes. Recordings performed during the 2nd postnatal week showed that the collicular units responding to tactile stimuli were rare and functionally immature. Starting from the beginning of the 3rd postnatal week, there was a dramatic increase of the number of somatosensory units and the appearance of an ordered topography, together with the maturation of the neuronal electrical properties. All the features of the adult collicular somatosensory map were found in the 3rd postnatal week, including the magnification of the vibrissae occupying the central portion of the visual field. The functional maturation of the collicular somatosensory map of the mouse is therefore a postnatal event which starts during the 3rd postnatal week, just after the opening of the eyes.
Article
Magnetic source imaging revealed that the topographic representation in the somatosensory cortex of the face area in upper extremity amputees was shifted an average of 1.5 cm toward the area that would normally receive input from the now absent nerves supplying the hand and fingers. Observed alterations provide evidence for extensive plastic reorganization in the adult human cortex following nervous system injury, but they are not a sufficient cause of the phantom phenomenon termed 'facial remapping'.
Article
Thresholds for detecting vibrotactile signals of variable frequency applied to the thenar eminence of the hand by small and large contactors were measured in subjects ranging in age from 10 to 89 years. Thresholds were found to increase as a function of age, but the rate of increase was greater after than before the age of 65 years. The rate of loss of vibrotactile sensitivity was substantially greater in the P channel (mediated by Pacinian corpuscles) than in the NP I channel (mediated by rapidly adapting fibers), the NP II channel (mediated by slowly adapting type II fibers), or the NP III channel (mediated by slowly adapting type I fibers). Women were frequently found to have greater sensitivity than men.
Article
We provide evidence for a perceptual marker of neuroplasticity in female mastectomy patients who reported phantom breast perceptions. When tactile stimuli were delivered to dorso-thoracic, shoulder and pinna regions ipsilateral to the mastectomy, these patients (in some cases even 5 days after the operation) referred the stimuli to the amputated breast mainly to the nipple. The somatosensory representation of the stimulated regions is probably adjacent to the former representation of the amputated breast. These results suggest that input from stimulated regions of the skin can drive neurones originally driven by input from the amputated breast. The apparent functional relation between pinna and nipple might give clues to the mechanisms underlying referred sensations and pain.
Article
Plasticity of sensory and motor cortical and subcortical representations in the adult brain appears to be a general phenomenon in animals that has now been extended to humans. There is a growing understanding of the mechanisms and rules that regulate the form and extent of reorganization; these appear to include activity-dependent control of synaptic efficacy, details of circuit arrangements, and growth of new axonal arbors. Of particular relevance to plasticity of cerebral cortical sensorimotor representations is recent evidence for the participation of intracortical horizontal pathways. These fibers provide a substrate for reorganization and contain mechanisms for increases or decreases in synaptic efficacy that depend on particular spatiotemporal activation patterns.
Article
We studied two human subjects with total deafferentation of one upper limb secondary to traumatic multiple cervical root avulsions. Both subjects developed a phantom limb and underwent elective amputation of the paralyzed, deafferentated limb. Psychophysical study revealed in each subject an area of skin in the pectoral region ipsilateral to the amputation where vibrotactile stimulation (VS) elicited referred sensations (RS) in the phantom limb. Positron emission tomography was then used to measure regional cerebral blood flow changes during VS of the pectoral region ipsilateral to the amputation with RS and during VS of a homologous part of the pectoral region adjacent to the intact arm without RS. A voxel-based correlation analysis was subsequently used to study functional connectivity. VS of the pectoral region adjacent to the intact arm was associated with activation of the dorsal part of the contralateral primary somatosensory cortex (S1) in a position consistent with the S1 trunk area. In contrast, VS of the pectoral region ipsilateral to the amputation with RS was associated with activation of the contralateral S1 that extended from the level of the trunk representation ventrally over distances of 20 and 12 mm, respectively, in the two subjects. The area of S1 activated during VS of the digits in a normal control subject was coextensive with the ventral S1 region abnormally activated during VS of the ectopic phantom representation in the two amputees, suggesting that the deafferented digit or hand/arm area had been activated by sensory input from the pectoral region. Correlation analysis showed an abnormal pattern of intrinsic connectivity within the deafferented S1 hand/arm area of both amputees. In one subject, the deafferented S1 was functionally connected with 3 times as many S1 voxels as the normally afferented S1. This abnormal functional connectivity extended in both the rostrocaudal and ventrodorsal dimensions. The results demonstrate that sensory input delivered to the axial body surface may gain access to the S1 hand/arm area in some humans who have suffered extensive deafferentation of this area. The findings are consistent with the hypothesis that deafferentation of an area of S1 may result in activation of previously dormant inputs from body surfaces represented in immediately adjacent parts of S1. The results also provide evidence that changes in functional connectivity between these adjacent areas of the cortex play a role in the somatotopic reorganization.
Article
Recent studies have begun to unravel the brain mechanisms that underlie the mental representation of the body. Imitation of movements by neonates suggests an implicit knowledge of the body structure that antedates the adult body schema. This can include inanimate objects that bear systematic relations to the body, as shown by the elimination from self awareness of a body part and its associated paraphernalia after selective brain lesions. Dynamic aspects of the body schema are revealed by spontaneous sensations from a lost body part as well as by orderly phantom sensations elicited by stimulation of body areas away from the amputation line and even by visual stimulation. The mechanisms of the body schema exhibit stability, since some brain regions seem permanently committed to representing the corresponding body parts in conscious awareness, and plasticity, since brain regions deprived of their natural inputs from a body part become reactive to inputs from other body parts.
Article
Cortical evoked potentials resulting from stimulation of the dorsal nerve of the penis (DNP) provide a unique opportunity to document the cortical localization of sexual sensory representation in man. The DNP supplies sensory axons to the major portion of the human phallus, including the penile shaft and glans. Animal and human studies indicate that this nerve plays a crucial role in erection and ejaculation. Direct cortical evoked responses to DNP electrical stimulation were recorded in patients undergoing preoperative evaluation for resection of epileptic foci. These studies provided evidence that the primary sensory cortex contains a large area of cortex devoted to the afferent fibers of the DNP and that the sensory field is in a different location than previously described. The location and distribution of this response indicated the need for revision of the traditional concept of the sensory cortical homunculus.