After removing the features traditionally used to define orgasm (here termed Onuf’s climax) what core phenomena remain?

The model below separates the orgasmic phase into determining and non-determining components as it transitions into the refractory period for both males and females. Quite notably, only non-determining factors can occur through many activities, drugs, and experiences that do not involve Onuf’s climax. Onuf’s climax is unique to the orgasm phase, as traditionally defined, which is why it is a gold standard measure.

Determining Factors

Onuf’s Climax must involve

• Neural integration reaching its given resonant threshold (top-down, bottom-up, in-brain potentiation to spinal control centers at S2-S4).
• Involuntary rhythmic contractions of pudendal-innervated muscles (levator ani, bulbospongiosus, anal sphincter, etc.) at ≈0.8–1 Hz, followed by progressively longer pauses. These bursts are generated by a spinal pattern generator and cannot be produced by voluntary Kegel contractions.
• Immediately after climax, strong neural inhibition (via dopamine suppression, opioid release, etc.) shuts down excitation for a reflex recovery/refractory period. Each orgasm builds increased post-orgasmic inhibition (refractory period) that must occur before Onuf’s reflex can fire again in both males and females whether the recover time is minutes, hours, or days. Note that this is unique from plateau phase burst contractions that resemble the Onuf’s climax contraction profile but differ in amplitude and inhibitory effect.

Non-Determining Factors

Onuf’s Climax can occur without

• Wakefulness (can occur in sleep or under anesthesia)
• Realization you are having Onuf’s climax (sleep orgasms, first orgasm experiences, muted orgasms)
• Desire to have a Onuf’s climax (non-consensual, persistent genital arousal disorder, as a side effect of medications or surgical procedures, or occurring from non-sexual activities like horseback riding, rope climbing)
• Penile, clitoral, or other genital stimulation (can occur with other bottom-up inputs with top-down inputs like fantasy, smut, or porn, including stimulation of nipple, foot, etc.)
• Erection or clitoral engorgement (can occur while flaccid)
• Intact penis or clitoris, such as following penile or clitoral amputation (via remaining dorsal nerves primarily; post-op transsexuals, clitorectomies, congenital variations)
• Ability to feel sensation (Can occur for some paralyzed individuals, especially with stronger vibrational stimulation; several examples on porn sites and in medical case studies)
• Ejaculation (Anejaculaton can occur).
• Vaginal lubrication (can occur with vaginismus as lubrication is not needed for stimulation but only assists in some forms of stimulation)
• Subjective pleasure (can be neutral, painful, mixed, or dysphoric)
• Heart rate spike (can have relatively low readings like 90 bpm)
• Vocalizations / moaning (can be stoic and silent)
• Body quivering / movements / full body movement like shuddering, trembling, quivering, legs shaking (can be completely still)
• Eyes rolling back / O-face (can be stoic or have a variety of facial expressions)
• Squirting & Skene’s emission
• Hyperventilation (can occur during slow meditative breathing)
• Sexual fantasy or porn (can occur in meditative state or thinking about just about any topic)
• Any particular emotional state or “valence”
• Cessation of stimulation (Onuf’s climax can occur while stimulation occurs; e.g., post-orgasmic torture; anal, vaginal, muffing, etc. penetration or light caresses)
• Several altered states, like trance, ecstatic absorption, dissociation, depersonalization, altered time perception, unity/merging states, synesthesia, time distortion, analgesia, out-of-body experiences, mystical/peak experiences, hyperesthesia, etc.
• Subjective pleasure (can be painful in prostatitis cases)
• Perceptions of bodily sensations: heart beating / increased heart rate; genital pulsation / throbbing in genitals, sweating, lower limb spasms, facial tingling, pelvic / genital contractions or spasms, whole-body trembling or quivering, flushing or warmth spreading, tingling in extremities, abdominal contractions, chest sensations
• Perception of subjective sensory dimensions: building sensations, flooding sensations, flushing sensations, shooting sensations, throbbing sensations, general spasms