Brain Activity Unique to Orgasm in Women: An fMRI Analysis

Abstract

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

Activation of sensory cortex by imagined genital stimulation: an fMRI analysis

“…Noteworthy, and unexpectedly, imagining dildo stimulation generated extensive brain activation in regions previously shown to be active in the process of genital stimulation leading up to and including orgasm (Komisaruk et al, 2004; Komisaruk & Whipple, 2005; Komisaruk, Wise, Frangos, & Allen, 2010; Komisaruk, Wise, Frangos, Birbano, & Allen, 2011; Wise, 2014; Wise et al, 2012; Wise, Frangos, & Komisaruk, (Submitted for publication)), whereas imagining speculum stimulation generated virtually no brain activation. Just thinking about stimulation by a dildo resulted in bilateral activation of the genital sensory cortex (paracentral lobule), as well as the secondary somatosensory cortex (the parietal operculum, OP4).…”

Reduced segregation and integration of structural brain network associated with sympathetic and dorsal penile nerve activity in anejaculation patients: a graph‐based connectome study

“…The events of peripheral neural system are under the control of spinal centers including the spinal generator of ejaculation (SGE) (Chehensse et al, 2016;Ch ehensse et al, 2017a,b;de Rodr ıguez-Peña et al, 2017), which is regulated by the excitatory and inhibitory inputs from the brain (Qin et al, 2017;Zhang et al, 2017;Atalay et al, 2019;Xu et al, 2019). Therefore, the brain is also responsible for these two phases and it is especially involved in the pleasant sensation produced by the orgasm reaction (Flannigan et al, 2018;Wise et al, 2017).…”

The clitoral activation paradox — Claimed outcomes from different methods of its stimulation

“…The pattern of brain scan results obtained and their interpretation cannot be compared to those obtained during natural coitus where the various genital structures are stimulated functionally all at the same time and multiple, connected brain regions are activated. This picture of brain activation was revealed in another imaging study of sexual arousal by Komisaruk and Whipple (2011), their 'Tapestry' representation of fMRI activity in 80 Brodman and other brain regions shows a widespread activity in the brain during arousal to orgasm while similar results were also obtained in a carefully controlled more recent study (Wise, Frangos, and Komisaruk, 2017), both results conflict with the previous punctate observations. Komisaruk (2010) has admitted that 'all major brain systems evidently contribute to women's orgasms'.…”