Can You Stomach Lying?

/ by Maggie Wittlin /

Being dishonest is something you can feel in your gut

Detective Slick sidled up to Johnnie Ray, who sat smugly in his small wooden chair, looking into the one-way mirror, picking the remnants of chicken chow fun out from his yellow teeth.

“I’m going to ask you this once, Johnnie,” Slick said. “Did you strangle Gertrude Muller?”

Johnnie Ray, whose ability to wring the necks of little old ladies was only surpassed by his knack for maintaining his heart rate during questioning, smiled and looked the detective in the eye.

“No, Slick. I did not kill poor Mrs. Muller.”

Immediately alarms sounded throughout the the station. Now it was Slick’s turn to look smug as he clasped the cuffs on a bewildered Johnnie Ray.

“Your eyes said ‘No,’ Johnnie,” Slick told him. “Your heart said ‘No.’ Your glands said ‘No.’ But your stomach, Johnnie Ray? Your stomach said, ‘Yeah, I killed that lady.’ And now you’re going to pay for it, Johnnie. You are going to pay dearly.”

The characters are fictional, but the possibility is real. According to a new study out of the University of Texas (UT), changes in the stomach’s pulse can signal the stress associated with lying—and can do so better than changes in a person’s heartbeat.

If the head researcher were to try to talk her way into a bar or even a voting booth, her stomach would go haywire. Trisha Pasricha, who conceived of the study and used her father’s lab equipment to carry it out, is just a junior at Clear Lake High School in Houston.

In her experiment, Trisha gave each of her 16 subjects a playing card, which each subject looked at privately. She then showed the subject projections of cards, each time asking, “Is this your card?” The subject was only to lie if the card on the screen was the one in their hand. Trisha, however, had an ace up her sleeve: She controlled the conditions so every subject told the truth twice and lied twice. Subjects were offered $20 if they could trick the electrogastrogram, a machine that monitors electric pulses in the stomach via external leads attached to the skin.

Not a single subject tricked the machine. The machine showed a substantial disruption in the normal stomach pulse when subjects lied about their cards.

And what—didn’t you not know that the stomach has a pulse? According to UT gastroenterologist and proud father P. Jay Pasricha, the gastrointestinal system has the workings of an entire brain spread out between muscle layers.

“The gut’s brain is probably, from an evolutionary perspective, older than the brain inside our head and it’s just as complex as the other nervous system,” he said.

Pasricha said this nervous system is generally independent from the central nervous system, but the two systems do communicate, giving people the lovely sensations of queasiness and nausea. The gastrointestinal nervous system works as a pacemaker for the stomach and intestines, keeping the stomach running at three cycles per minute, he said. When a person is under stress, the stomach departs from its normal cycle.

Right now polygraphs have an accuracy of about 90%. While Trisha and her father freely admit that their study was only preliminary, they believe stomach monitoring will improve upon existing polygraphs.

“Countermeasures a subject can take to avoid detection such as regulating breathing patterns or putting anit-perspirant on the fingers…will be more difficult to do with the electrical activity in the stomach,” Trisha said via e-mail.

She also said that the equipment needed to monitor the stomach only costs about $5,000, much less than the several million-dollar price tag on an fMRI machine, which scientists currently hope will act as an improved polygraph.

Originally published November 1, 2005

Tags communication data research

Share this Stumbleupon Reddit Email + More


  • Ideas

    I Tried Almost Everything Else

    John Rinn, snowboarder, skateboarder, and “genomic origamist,” on why we should dumpster-dive in our genomes and the inspiration of a middle-distance runner.

  • Ideas

    Going, Going, Gone

    The second most common element in the universe is increasingly rare on Earth—except, for now, in America.

  • Ideas

    Earth-like Planets Aren’t Rare

    Renowned planetary scientist James Kasting on the odds of finding another Earth-like planet and the power of science fiction.

The Seed Salon

Video: conversations with leading scientists and thinkers on fundamental issues and ideas at the edge of science and culture.

Are We Beyond the Two Cultures?

Video: Seed revisits the questions C.P. Snow raised about science and the humanities 50 years by asking six great thinkers, Where are we now?

Saved by Science

Audio slideshow: Justine Cooper's large-format photographs of the collections behind the walls of the American Museum of Natural History.

The Universe in 2009

In 2009, we are celebrating curiosity and creativity with a dynamic look at the very best ideas that give us reason for optimism.

Revolutionary Minds
The Interpreters

In this installment of Revolutionary Minds, five people who use the new tools of science to educate, illuminate, and engage.

The Seed Design Series

Leading scientists, designers, and architects on ideas like the personal genome, brain visualization, generative architecture, and collective design.

The Seed State of Science

Seed examines the radical changes within science itself by assessing the evolving role of scientists and the shifting dimensions of scientific practice.

A Place for Science

On the trail of the haunts, homes, and posts of knowledge, from the laboratory to the field.


Witness the science. Stunning photographic portfolios from the pages of Seed magazine.

SEEDMAGAZINE.COM by Seed Media Group. ©2005-2015 Seed Media Group LLC. All Rights Reserved.

Sites by Seed Media Group: Seed Media Group | ScienceBlogs | Research Blogging | SEEDMAGAZINE.COM