The physiological processes that occur in the brain and spinal cord during orgasm are poorly understood.
Some research suggests that the cerebral cortex and spinal cord work together to produce this intense sensation. When stimulated properly, the brain sends signals to the spine through the central nervous system to trigger an involuntary reflex that causes muscle contractions. This phenomenon is known as the "orgasmic reflex," which results in the release of pleasure hormones such as dopamine and oxytocin. The exact mechanism for how these signals travel from the brain to the spine remains unclear; however, there may be multiple pathways involved.
One theory posits that dopamine plays a key role in regulating the flow of excitatory and inhibitory neurotransmitters in the spinal cord. During arousal, dopamine increases the activity of neurons, which then releases more excitatory chemicals like glutamate. These increased levels of excitation cause electrical impulses to spread along the spine, eventually reaching the sacral region where they trigger a series of muscle contractions. At the same time, serotonin acts as an inhibitor, preventing too much excitement and reducing excessive muscle contraction. It's possible that this interplay between dopamine and serotonin helps balance the intensity of the orgasmic response and prevents over-stimulation of the muscles.
Other researchers believe that the orgasmic reflex originates from the brainstem rather than the spine. They suggest that when certain regions of the brainstem are activated during sexual stimulation, they send signals directly to the genitals and pelvic floor to produce physical responses. These areas include the locus coeruleus (LC), ventral tegmental area (VTA), substantia nigra (SN), and dorsal raphe nucleus (DRN). The LC is responsible for producing noradrenaline, which has been shown to increase during sexual arousal. The VTA and SN contain dopaminergic neurons that respond to natural rewards such as food or social interactions.
DRN produces serotonin, which can modulate various aspects of mood and emotion. Together, these brain areas may work together to regulate sexual pleasure and orgasmic intensity.
While scientists have made progress in understanding the neurological mechanisms behind orgasms, there is still much left to learn about how exactly it happens in the body. Further study will likely reveal even more complex interactions between different parts of the nervous system that contribute to this pleasurable sensation.
It's important to remember that orgasms are a highly personal experience unique to each individual—no two people will have identical physiological responses.
Which spinal and cortical mechanisms coordinate muscular activity during orgasm?
The brain controls various physiological responses during sexual arousal and orgasm through the hypothalamus, which sends impulses to the pituitary gland and other endocrine glands to secrete hormones that influence sexual behavior and sensation. During sexual arousal, the brain releases dopamine, norepinephrine, and serotonin, which increases heart rate and blood flow to the genital area.