Journalist Mary Roach has investigated the nitty gritty of space travel, cadaver research and the afterlife. But at TED2009, she shared some of her most fascinating research yet … into the orgasm.

Mary Roach: 10 things you didn't know about orgasm

In her talk “10 things you didn’t know about orgasm,” Roach digs deep into scientific research in sexuality — much of it recent, much of it ancient — and shares several hilarious and disturbing thoughts. It’s simply a must-watch. This week’s TEDWeekends on the Huffington Post digs deeper into the talk, with essays from Roach and several others. Read some selections here.

Mary Roach: Let’s Talk About Orgasm

In 2009, I walked onto the TED stage and gave a talk that included video of a Danish pig inseminator. The topic of the talk was orgasm, and the video related to a centuries-old debate over “upsuck”: that is, whether the contractions of the uterus during orgasm serve to draw the semen toward the egg and boost the odds of conception. In pigs, research suggests, this is the case. The inseminator up on the screen was practicing the Five-Point Stimulation Plan, a technique developed by Denmark’s National Committee for Pig Production, following research that showed a 6 percent higher farrowing rate among titillated sows. In other words, as a group, they produced 6 percent more piglets than sows inseminated while idly standing around the sty.

William Masters and Virginia Johnson, the pioneering sex researchers of the ’50s and ’60s, were upsuck skeptics. They didn’t believe orgasm facilitated conception, at least not in humans, and they worried that the belief might be hobbling fertility research. So they set out to prove their case. Read the full essay >>

Marnia Robinson: Why Stop Orgasm Research at Climax?

Mary Roach’s irreverent orgasm trivia reminds us that researchers, like porn makers, tend to snap their notebooks shut right after the money shot. Yet some of the most intriguing findings about orgasm may lie beyond its brief fireworks. Post-O data could one day help solve all kinds of mysteries, such as why lovers’ libidos often go out of sync — especially after those initial“honeymoon poppers” wear off.

After a rat satiates himself sexually (which is how rats normally mate, and requires an average of 2.5 hours and up to 7 ejaculations), he exhibits a pronounced 4-day cycle. He’s a bit fragile. His sexual motivation (libido) is nil-to-sluggish, and he’s hyper-reactive to a range of drugs. Why does this happen? Read the full essay >>

Robert Koehler: The Sex Closet

Mary Roach’s TEDTalk is about … well, our giggling, collective discomfort with the human body and its processes.

While we can publicly talk about sex in all its thrilling messiness with a little more candor than we could a few generations back, we still live most of our lives within an invisible envelope of politeness. What interested me about the video at least as much as the actual stuff I learned — for instance, that the longest ejaculation of sperm Dr. Kinsey ever measured was 8 ft. — was the fact that the TED audience (and I) laughed at it all. Why is this so funny? Why does explicit commentary on sexual arcana summon up the public guffaws? Read the full essay >>