Described as a powerful, pleasurable release of accumulated sexual tension, the orgasm is perceived as the epitome of sexual pleasure for both men and women.
During orgasm, an individual may experience a rise in blood pressure an increased heart rate, heavy breathing, and rhythmic muscular contractions.
But while the signs and sensations of an orgasm might be clear, the underlying mechanisms of this sexual response - particularly its neurophysiological effects - remain uncertain.
Study author Adam Safron, Ph.D., of the Weinberg College of Arts and Sciences at Northwestern University in Evanston, IL, notes that the majority of research relating to the orgasm has focused on its evolutionary functions.
A study reported by Medical News Today earlier this year did just that; researchers suggested that the female orgasm once played in ovulation.
For this latest study - recently reported in the journal Socioaffective Neuroscience and Psychology - Safron set out to gain a better understanding of how the human orgasm affects the brain.
Safron analyzed an abundance of studies and literature that have investigated the brain and body's response to sexual stimulation.
He used the information to create a model that sheds light on how rhythmic sexual activity affects rhythmic activity in the brain.
Safron explains that rhythmic sexual stimulation - if intense enough and if it lasts long enough - can boost neural oscillations at correlating frequencies, a process called "neural entrainment."
This process may be responsible for what Safron describes as a "sexual trance," where sole focus is on the immediate sensation experienced.
"The idea that sexual experiences can be like trance states is in some ways ancient. Turns out this idea is supported by modern understandings of neuroscience.
In theory, this could change the way people view their sexuality. Sex is a source of pleasurable sensations and emotional connection, but beyond that, it's actually an altered state of consciousness."
Adam Safron, Ph.D.
Interestingly, Safron also identified similarities between orgasms and reflex seizures, noting that both of these experiences can be triggered by rhythmic stimulation that induces rhythmic activity in the brain.
Additionally, the researcher found that the way the brain reacts to rhythmic sexual stimulation is comparable to the way it responds to rhythmic music and dance.
"[...] although obvious in retrospect, I wasn't expecting to find that sexual activity was so similar to music and dance, not just in the nature of the experiences, but also in that evolutionarily, the rhythm-keeping ability may serve as a test of fitness for potential mates," says Safron.
He adds that rhythmic music and dance have served as a key part of mating for hundreds of millions of years, and his findings are consistent with this fact.
Safron says much more work needs to be done to fully understand the neurophysiological effects of orgasms, but he hopes his study paves the way for such research.
"Before this paper, we knew what lit up in the brain when people had orgasms, and we knew a lot about the hormonal and neurochemical factors in non-human animals, but we didn't really know why sex and orgasm feel the way they do," he says. "This paper provides a level of mechanistic detail that was previously lacking."