Fig 4 - uploaded by Nan Wise
Content may be subject to copyright.
Regions activated by tactile self-stimulation of the clitoris ! imagined self-stimulation of the clitoris. Top left: premotor cortex BA6 left side of brain. Top right: primary somatosensory cortex BA3a left. Bottom left: secondary somatosensory cortex OP1 right. Bottom right: cerebellum right. (Cluster z01.0, p B0.01, N 011; MNI_152 coordinate: z 0 56/ 48/ ( 42/22). The above contrast is CTS ! CIS.
Source publication
Background:
During the course of a previous study, our laboratory made a serendipitous finding that just thinking about genital stimulation resulted in brain activations that overlapped with, and differed from, those generated by physical genital stimulation.
Objective:
This study extends our previous findings by further characterizing how the b...
Context in source publication
Citations
... The sense of touch provides a direct stimulus, involving immediate physical contact, while remote sensory modalities, such as vision and hearing, rely on indirect stimuli to convey information about the external world. Furthermore, sexual fantasies are often determined through mental images (Lehmiller & Gormezano, 2023), and arousal can be triggered by mental imagery (Ågmo & Laan, 2022;Whipple et al., 1992;Wise et al., 2016). Despite the different nature of these stimuli types, the processing of imaginative and tactile stimuli is still covered by the concept proposed. ...
Sexuality is an integral part of human nature, yet we know little about its origins and underlying mechanisms. Understanding how the brain processes sexual stimuli is crucial for advancing our knowledge of the origins of sexuality and its variations. Only if a stimulus was internally evaluated as ‘attractive’ the information can progress to evoke sexual desire or arousal. Importantly, such evaluation processes require an internal reference against which external information is compared. These processes, however, remain largely unexplored, and hence we still do not understand why we are attracted to what we are attracted to. By synthesizing the existing literature and integrating existing models, this narrative review proposes a novel neuroscientific framework on sexuality, addressing key theoretical gaps. As a result, the concept of sexual priors in the brain is introduced. Within this framework, sexual priors refer to mental ‘images’ representing a collection of internally stored information of what we regard as sexually attractive. Such mental representations act as reference in early internal evaluation processes of sexual stimuli. It is suggested that sexual priors are (partly) innate and sex-specific, contributing to heterosexuality. Evolutionary aspects that could explain the development of these priors are discussed. Furthermore, the framework provides possible explanations for variations in sexual orientation through potential cross-sex shifts in sexual prior content. The refinement of sexual prior content over time may explain the diversity of sexual interests and attraction patterns among humans. Moreover, the concept can be applied to a variety of psychiatric conditions related to atypical and maladaptive sexual behaviors. A proposition is put forward regarding brain areas and networks that may be involved in the formation of sexual priors, serving as potential targets for future research. In summary, by integrating sexual priors into models of sexual stimuli processing, this article fills theoretical gaps while inspiring further research. This work aims to enhance understanding of sexuality, which ultimately could increase social awareness, foster tolerance, and promote psychological well-being.
... The male and female genitalia, including the breasts, have a high aesthetic and erotic appreciation. This was confirmed by functional MRI of volunteers imagining sexual excitement [42] or watching sexual videos [42]. The MRI revealed an activation of the bilateral genital sensory area in the paracentral lobule of the cerebral hemisphere, and the secondary somatosensory cortex in the parietal operculum, as well as of the cingulate cortex, hippocampus, hypothalamus, ventral striatum, amygdala, medulla, and cerebellum. ...
... The male and female genitalia, including the breasts, have a high aesthetic and erotic appreciation. This was confirmed by functional MRI of volunteers imagining sexual excitement [42] or watching sexual videos [42]. The MRI revealed an activation of the bilateral genital sensory area in the paracentral lobule of the cerebral hemisphere, and the secondary somatosensory cortex in the parietal operculum, as well as of the cingulate cortex, hippocampus, hypothalamus, ventral striatum, amygdala, medulla, and cerebellum. ...
... The "erogenous" and orgasmic regions of the brain are also activated, e.g. the medial prefrontal cortex, the left insula, nucleus accumbens, amygdala, ventral tegmental area, and the substantia nigra [43,44]. They are a part of the brain reward system, i.e. hedonic structures [17,42,44]. A coitus performance is regulated by the hypothalamic preoptic area and some other structures [44]. ...
There is not one single article in the available literature dealing with internal aesthetics. Two brains were dissected by us, a radiogram of 1 brain was performed, 2 heads and 1 trunk were serially sectioned, and vascular casts were made of several organs. Finally, 210 histologic slices of various specimens were made. Historically, some animal and human organs, or their models, especially of the heart and liver, were used for a future prediction or as votive items in ancient times. Later on, the sacred heart was often painted in the portraits of Christ. Da Vinci and Vesalius during the Renaissance artistically presented the aesthetics of many organs, including Bourgery and Pernkopf some 3 and 4 centuries later. Modern digital artists presented them in 3D. In conclusion, gifted individuals in the Paleolithic and Neolithic times, in the ancient civilizations, and in the antique period depicted several organs, mainly for religious reasons. From the Renaissance onward, and particularly in modern times, the aesthetics of virtually all organs was shown in anthropology, fine art, and medicine.
... The physiological responses to imagery-induced orgasm and orgasm produced by clitoral stimulation are identical. Furthermore, the brain areas activated after both kinds of orgasms are similar (Wise et al., 2016). Men also show genital responses to mental representations of sexual stimuli (e.g. ...
Sexual motivation (desire) requires the simultaneous presence of an active central motive state and a stimulus with sexual significance. Once activated, sexual motivation leads to visceral responses and approach behaviors directed toward the emitter of the sexual stimulus. In humans, such behaviors follow cognitive evaluation of the context, including predictions of the approached individual’s response. After successful approach and establishment of physical contact, manifest sexual activities may be initiated. Sexual interaction is associated with and followed by a state of positive affect in most animals, whereas aversive consequences may be experienced by humans. The affective reactions may become associated with stimuli present during sexual interaction, and these stimuli may thereby alter their incentive properties. Here we show how the incentive motivation model can be used to explain the origins and possible treatments of sexual dysfunctions, notably disorders of desire. We propose that associations formed between negative outcomes of sexual interaction and the salient stimuli, for example, the partner, underlies hypoactive desire disorder. Highly positive outcomes of sexual interaction enhance the incentive value of the stimuli present, and eventually lead to hyperactive sexual desire. Treatments aim to alter the impact of sexual incentives, mainly by modifying cognitive processes.
... Hier zeigte sich eine massiv vermehrte Erregung im parazentralen Lobulus (primärer sensorischer Kortex für genitale Reize, "sensorischer Homunkulus") im Vergleich zu einem deutlich geringer reaktiven Normalkollektiv. Wise et al. (2016) zeigten, dass eine alleinige imagi native Beschäftigung mit sexueller Stimulation deutliche Aktivitäten im sensorischen Kortex bewirkte, ohne dass eine periphere Stimulation erfolgte. Somit kann auch das Gehirn als "Startorgan" der sexuellen Erregung betrachtet werden, und nicht ausschließlich die Klitoris. ...
... Current taskbased fMRI has become more sophisticated, involving tasks that might test attention abilities, responses to movies or song clips, or sensory self-stimulation of different bodily and genital regions to map the brain pathways that underlie these responses. 15,17,38 For task-based fMRI, the main research design options are event-related and block design ( Figure 2). Event-related (ER) design refers to presenting stimuli with a variable inter-trial interval of sufficiently long duration to allow BOLD signal for multiple conditions to be separately extracted and analyzed. ...
Background
Over the past 30 years, functional magnetic resonance imaging (fMRI) has emerged as a powerful tool to non-invasively study the activity and function of the human brain. But along with the potential of fMRI to shed light on neurological, psychiatric, and psychological processes, there are methodological challenges and criticisms.
Aim
We herein provide an fMRI primer designed for a diverse audience, from the neuroimaging novice to the experienced user.
Methods
This primer is structured as follows: Part 1: Overview: “What is fMRI and what can it tell us?.” Part 2: Basic fMRI principles: MR physics, the BOLD signal, and components of a typical scan session. Part 3: Basic fMRI experimental design: why timing is critical, and common sources of noise in the signal. Part 4: Basic fMRI analysis methods: software, the 3 stages of data analysis (preprocessing, individual, and group level), and a survey of advanced topics and methods including connectivity, machine learning, and assessing statistical significance. Part 5: Criticism, crises, and opportunities related to power of studies, computing requirements, logistical, and interpretational challenges, and methodological debate (assessing causality, circular correlations, and open science best practices).
Outcomes n/a Clinical Translation
fMRI has primarily been used in clinical research to elucidate the brain correlates of sexual behavior. The translational potential of the method into clinical practice has not yet been realizedfMRI has primarily been used in clinical research to elucidate the brain correlates of sexual behavior. The translational potential of the method into clinical practice has not yet been realized
Strengths and Limitations
fMRI is a useful and powerful tool for understanding the brain basis of human sexuality. However, it is also expensive, requires extensive methods expertise, and lacks the precision needed to be immediately translatable to clinical practice. The recency of the method, need for basic research, technical limitations, as well as inherent variability in individuals brain activity also impact the pace at which fMRI for sexual medicine can move from the scanner to the clinic.
Conclusion
This primer provides the novice an understanding of the appropriate uses and limitations of fMRI, and for the experienced user, a concise update on current issues and methodological advances.
Mills-Finnerty C, Frangos E, Allen K, et al. Functional Magnetic Resonance Imaging Studies in Sexual Medicine: A Primer. J Sex Med 2022;XX:XXX–XXX.
... Furthermore, humans may obtain sexual reward in the absence of genital stimulation. Women may experience orgasm through the exclusive use of sexual fantasies, and such orgasms have the same endocrine and neural manifestations as orgasms induced by mechanical stimulation of the clitoris (Whipple et al., 1992;Wise et al., 2016). There is also anecdotal evidence suggesting that men can achieve orgasms through fantasies (Klumbies and Kleinsorge, 1950). ...
Sexual incentive stimuli activate sexual motivation and heighten the level of general arousal. The sexual motive may induce the individual to approach the incentive, and eventually to initiate sexual acts. Both approach and the ensuing copulatory interaction further enhance general arousal. We present data from rodents and humans in support of these assertions. We then suggest that orgasm is experienced when the combined level of excitation surpasses a threshold. In order to analyze the neurobiological bases of sexual motivation, we employ the concept of a central motive state. We then discuss the mechanisms involved in the long- and short-term control of that state as well as those mediating the momentaneous actions of sexual incentive stimuli. This leads to an analysis of the neurobiology behind the interindividual differences in responsivity of the sexual central motive state. Knowledge is still fragmentary, and many contradictory observations have been made. Nevertheless, we conclude that the basic mechanisms of sexual motivation and the role of general arousal are similar in rodents and humans.
... Even more interestingly, sights of touching evoke activity in somatosensory cortex (Hansson et al., 2009), visual cues to an object's surface properties evoke activity in secondary somatosensory cortex (Sun, Welchman, Chang, & Luca, 2016), and the mere sight of photographs (Proverbio, D'Aniello, Adorni, & Zani, 2011), and lipreading (watching a speaker's lips during face-to-face conversation; Calvert et al., 1997) activate auditory cortex. These particular findings together suggest the role of crossmodal mental imagery, the formation of mental image in a sensory modality from the stimulation or experience in another sensory modality, in perception and neuroplasticity: what people imagine in their minds can affect how they perceive the world, and how the sensory cortex reorganizes in absence of actual stimulation (e.g., Berger & Ehrsson, 2018;Nanay, 2018;O'Dowd, Cooney, McGovern, & Newell, 2019;Schmidt & Blankenburg, 2019;Spence & Deroy, 2013;Wise, Frangos, & Komisaruk, 2016). However, perhaps mental imagery cannot be generated before relaying input signals from the first, stimulated sensory cortex on to the second, nonstimulated sensory cortex, such that the role of mental imagery that operates in a top-down manner does not preclude the process of crossmodal connectivity. ...
... Such a possibility is very unlikely in cutting-edge neuroimaging studies, like those outlined above, in which participants are required to keep their eyes closed (Brodoehl, Witte, & Klingner, 2016), unless the purpose of the study is not to examine the effects of saccades or eye movements (e.g., Sylvester et al., 2005). However, as discussed before, the role of mental imagery in such crossmodal effects in normal humans cannot be precluded (e. Wise et al., 2016). However, the pivotal role of mental imagery in the activation of nonstimulated sensory cortices does not contradict the innate nature of crossmodality. ...
Objective:
Neuroplasticity enables the brain to establish new crossmodal connections or reorganize old connections which are essential to perceiving a multisensorial world. The intent of this review is to identify and summarize the current developments in neuroplasticity and crossmodal connectivity, and deepen understanding of how crossmodal connectivity develops in the normal, healthy brain, highlighting novel perspectives about the principles that guide this connectivity.
Methods:
To the above end, a narrative review is carried out. The data documented in prior relevant studies in neuroscience, psychology and other related fields available in a wide range of prominent electronic databases are critically assessed, synthesized, interpreted with qualitative rather than quantitative elements, and linked together to form new propositions and hypotheses about neuroplasticity and crossmodal connectivity.
Results:
Three major themes are identified. First, it appears that neuroplasticity operates by following eight fundamental principles and crossmodal integration operates by following three principles. Second, two different forms of crossmodal connectivity, namely direct crossmodal connectivity and indirect crossmodal connectivity, are suggested to operate in both unisensory and multisensory perception. Third, three principles possibly guide the development of crossmodal connectivity into adulthood. These are labeled as the principle of innate crossmodality, the principle of evolution-driven 'neuromodular' reorganization and the principle of multimodal experience. These principles are combined to develop a three-factor interaction model of crossmodal connectivity.
Conclusions:
The hypothesized principles and the proposed model together advance understanding of neuroplasticity, the nature of crossmodal connectivity, and how such connectivity develops in the normal, healthy brain.
... Lifelong PE patients had decreased FC density in thalamus (17) as well as decreased FC involved in S1 (16). Furthermore, genital stimuli induced increased brain activation in sensory and motor cortex including the S1 and premotor cortex in HCs (52). Meanwhile, a recent study reported the increased excitability of motor cortex whether in heterosexual or homosexual healthy males (53) by visual sexual stimuli, which revealed the participation of motor except aforementioned sensory in sexual behavior. ...
Background:
Lifelong premature ejaculation (PE) is one common male sexual dysfunction and is implicated in widespread structural and functional abnormalities of bilateral hemispheres. However, whether the inter-hemisphere functional connectivity (FC) of lifelong PE patients was altered still remain unclear.
Methods:
Thirty-four lifelong PE patients and 30 healthy controls (HCs) were enrolled in this study and all underwent T1-weighted and resting-state functional MRI (fMRI) scan. The voxel-mirrored homotopic connectivity (VMHC) measure and independent sample t-test were applied to examine the alterations of VMHC values in the patients relative to HCs with the significant threshold at P<0.05, false discovery rates corrected. Correlation analysis was adopted to calculate the relationships between the imaging results and clinical characteristics of patients (P<0.05, Bonferroni corrected). Receiver operating characteristic (ROC) curve analysis was performed to investigate the possible biomarkers for distinguishing the patients from the HCs using the VMHC values of inter-group differences.
Results:
The results revealed that compared with HCs, lifelong PE patients had higher VMHC values in the precentral gyrus (PG), primary somatosensory cortex (S1), supplementary motor area (SMA), precuneus, middle temporal cortex (MTC), superior temporal pole (STP), thalamus, caudate and middle cingulate cortex (MCC). Correlation analysis showed that the mean VMHC values in the S1 negatively correlated with intravaginal ejaculation latency time (IELT) in the patient group. Furthermore, the caudate revealed the well classification power from the ROC analysis.
Conclusions:
The present study showed the abnormal inter-hemisphere interaction and integration of information involved in ejaculation inhibitory control, sensorimotor mediation and self-reference processing including the thalamus, caudate, MCC, widespread parietal cortex and temporal cortex in lifelong PE patients compared with HCs. Correlation analysis and ROC analysis revealed the importance of S1 and caudate in lifelong PE. Notably, the ROC result of caudate might show the core roles of caudate played in the pathophysiology of lifelong PE.
... The figure contrasts the PGAD activation with that in women who did not have PGAD and who just imagined clitoral stimulation. 59 Based on anecdotal reports, it is possible that catastrophization is related more to distressing dysesthesia of the genitals than of other pelvic regions (eg, bladder or legs), suggesting the existence of a neurological process that may be unique to the genitals rather than to generalized emotional distress. Further research is needed to map the projections to and from the paracentral lobule and other brain regions that are likely involved in various genitopelvic sensations of PGAD/GPD (eg, arousal, awareness, discomfort, itch, pain) and the associated emotional distress (eg, catastrophization, suicidality). ...
Background
Persistent genital arousal disorder (PGAD), a condition of unwanted, unremitting sensations of genital arousal, is associated with a significant, negative psychosocial impact that may include emotional lability, catastrophization, and suicidal ideation. Despite being first reported in 2001, PGAD remains poorly understood.
Aim
To characterize this complex condition more accurately, review the epidemiology and pathophysiology, and provide new nomenclature and guidance for evidence-based management.
Methods
A panel of experts reviewed pertinent literature, discussed research and clinical experience, and used a modified Delphi method to reach consensus concerning nomenclature, etiology, and associated factors. Levels of evidence and grades of recommendation were assigned for diagnosis and treatment.
Outcomes
The nomenclature of PGAD was broadened to include genitopelvic dysesthesia (GPD), and a new biopsychosocial diagnostic and treatment algorithm for PGAD/GPD was developed.
Results
The panel recognized that the term PGAD does not fully characterize the constellation of GPD symptoms experienced by patients. Therefore, the more inclusive term PGAD/GPD was adopted, which maintains the primacy of the distressing arousal symptoms and acknowledges associated bothersome GPD. While there are diverse biopsychosocial contributors, there is a common underlying neurologic basis attributable to spontaneous intense activity of the genitopelvic region represented in the somatosensory cortex and its projections. A process of care diagnostic and treatment strategy was developed to guide the clinician, whenever possible, by localizing the symptoms as originating in any of five regions: (i) end organ, (ii) pelvis/perineum, (iii) cauda equina, (iv) spinal cord, and (v) brain. Psychological treatment strategies were considered critical and should be performed in conjunction with medical strategies. Pharmaceutical interventions may be used based on their site and mechanism of action to reduce patients’ symptoms and the associated bother and distress.
Clinical Implications
The process of care for PGAD/GPD uses a personalized, biopsychosocial approach for diagnosis and treatment.
Strengths and Limitations: Strengths include characterization of the condition by consensus, analysis, and recommendation of a new nomenclature and a rational basis for diagnosis and treatment. Future investigations into etiology and treatment outcomes are recommended. The main limitations are the dearth of knowledge concerning this condition and that the current literature consists primarily of case reports and expert opinion.
Conclusion
We provide, for the first time, an expert consensus review of the epidemiology and pathophysiology and the development of a new nomenclature and rational algorithm for management of this extremely distressing sexual health condition that may be more prevalent than previously recognized.
Goldstein I, Komisaruk BR, Pukall CF, et al. International Society for the Study of Women’s Sexual Health (ISSWSH) Review of Epidemiology and Pathophysiology, and a Consensus Nomenclature and Process of Care for the Management of Persistent Genital Arousal Disorder/Genito-Pelvic Dysesthesia (PGAD/GPD). J Sex Med 2021;XX:XXX–XXX.
... Corresponding areas of the somatosensory cortex are activated both when an individual is touched and also during the anticipation of touch (Carlsson, Petrovic, Skare, Petersson, & Ingvar, 2000;Drevets et al., 1995), and the same holds for mental imagery of touch as compared to physical touch (Yoo, Freeman, McCarthy, & Jolesz, 2003). Similarly, imagined genital stimulation activates several of the same brain areas, including genital regions of S1, as actual genital stimulation (Wise, Frangos, & Komisaruk, 2016). Furthermore, visually induced anticipation of touch enhances body-awareness (Ferri, Chiarelli, Merla, Gallese, & Costantini, 2013) and visual enhancement of tactile sensations has been widely reported (Haggard, 2006;Serino, Pizzoferrato, & Làdavas, 2008). ...
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.
