Welcome to a whirlwind tour of ten fascinating scientific discoveries about laughter, the universal soundtrack of joy that links us across cultures, species, and even brain regions. Below, each numbered entry unpacks a quirky study, complete with vivid details, eye‑catching images, and a dash of humor.
10 Babies and Chimps
Chimpanzees are our closest living relatives, so it isn’t surprising that they share many traits with us. A 2018 investigation added laughter to that roster—at least for the tiniest humans. Researchers from several European universities gathered video clips of 44 infants aged three to 18 months, simply by mining the internet for adorable laughing moments.
The team focused on whether the giggles occurred during inhalation or exhalation. One hundred‑two psychology students rated each clip for breath‑phase. Younger babies produced laughs both while inhaling and exhaling, mirroring chimpanzee vocalizations. Older infants shifted toward exhalation‑only chuckles, the pattern typical of adult humans.
These shifts weren’t linked to any single developmental milestone; instead they appeared to drift gradually as the babies added months to their age. The investigators noted that their ratings came from non‑experts and planned follow‑up work with professional phoneticians to confirm the findings.
According to study leader Dr. Disa Sauter, there’s no consensus on why humans predominantly laugh on exhalation while chimps do not. One hypothesis points to our superior vocal control. Future research may explore whether the inhalation‑exhalation balance ties to the cause of the laugh, or whether similar breathing changes occur in other vocal expressions.
9 Fake Laughter
We all have moments when we chuckle out of politeness rather than genuine amusement—think of the courteous snort at a boss’s joke. A 2018 study by Dr. Greg Bryant at UCLA revealed that people worldwide are surprisingly adept at spotting such phony giggles.
The researchers presented 884 participants from 21 nations across six continents with recordings of spontaneous laughter captured during natural conversation and with volitional laughs that speakers produced on command. Listeners, regardless of cultural background, distinguished real from fake laughs at rates above chance.
Performance varied: Samoan participants identified authentic laughs correctly 56 % of the time, while Japanese listeners achieved a 69 % success rate. Dr. Bryant explained that fake laughter tends to sound more speech‑like, whereas genuine laughter carries distinct acoustic signatures that transcend cultural boundaries.
8 Canned Laughter
Laugh tracks—those pre‑recorded bursts of mirth that punctuate sitcoms—might seem passé, but research suggests they still boost perceived funniness. Dr. Sophie Scott of University College London led a 2019 experiment featured in Current Biology, examining how laugh tracks affect the reception of notoriously weak “dad jokes.”
Participants heard four intentionally bad jokes (e.g., “What state has the smallest drinks? Mini‑soda!”) followed by either no laughter, a fake laugh track, or a genuine one. Seventy‑two volunteers rated each joke on a seven‑point scale.
The presence of any laugh track lifted the humor ratings: fake laughter added roughly ten percent, while authentic laughter contributed a fifteen‑to‑twenty‑percent bump. Even subpar jokes seemed funnier when accompanied by a chorus of giggles.
7 Immunity
A 2003 study probed whether laughter could give the immune system a boost, focusing on natural‑killer (NK) cells, which patrol the body for rogue cells. Thirty‑three healthy adult women from a Midwestern rural community were split into two groups.
The experimental cohort watched a comedy clip—choices included Bill Cosby, Tim Allen, or Robin Williams—while the control group viewed a tranquil tourism video. Researchers measured participants’ blood pressure and drew blood before and after the viewing.
Simply watching a funny video didn’t automatically raise NK‑cell activity. However, the Humor Response Scale (HRS) scores, reflecting how funny subjects found the clip, correlated positively with NK‑cell activation. Women who rated the comedy highly (HRS ≥ 25) showed the strongest immune response, whereas those who didn’t find the video amusing actually experienced a dip in NK‑cell activity.
6 Dominance
Power isn’t just felt—it can be heard. Dr. Christopher Oveis of UC San Diego discovered that high‑status individuals emit laughter with distinctive acoustic traits, and observers pick up on those cues.
In 2014, the researcher filmed four fraternity brothers—two newcomers and two long‑standing members—while they teased each other. Independent raters, unaware of the study’s purpose, evaluated the laughter for dominance, loudness, and pitch. Dominant laughs were louder, higher‑pitched, and more variable in tone. New pledges only displayed dominant laughter when they were the teasing party, whereas veteran members laughed dominantly regardless of who was being teased.
A follow‑up study in 2016 presented 51 students with twenty recordings of the same laughs. Listeners consistently judged dominant‑sounding laughers as higher in social status, even when the dominant laugh came from a new pledge. Conversely, a submissive‑sounding laugh from an established frat brother was still perceived as high‑status, suggesting that the acoustic signature of dominance can override actual hierarchy.
5 Psychopathy
Laughter’s contagion may not reach everyone. A 2017 study at University College London examined whether boys predisposed to adult psychopathy show a muted response to genuine laughter.
The researchers recruited 92 males aged 11‑16: 30 “typical” controls and 62 displaying disruptive behaviors, of which some also exhibited callous‑unemotional traits. While undergoing fMRI scans, participants listened to recordings of spontaneous laughter, forced laughter, and crying, then rated how much each sound made them want to experience the associated emotion.
All participants’ brains lit up to genuine laughter, but those with both disruptive conduct and callous‑unemotional traits showed reduced activation in the supplementary motor area and anterior insula—regions linked to mirroring laughter and feeling others’ emotions. Even the subgroup with only disruptive behavior displayed a milder reduction. Dr. Essi Viding noted that it remains unclear whether the blunted neural response is a cause or consequence of the behavioral traits, but the findings warrant deeper investigation.
4 Appetite
Can a good belly laugh stir your stomach? A 2010 experiment by Dr. Lee S. Berk, Dr. Jerry Petrofsky, and colleagues explored how “mirthful laughter” (a form of eustress) influences appetite‑regulating hormones.
Fourteen volunteers watched a comedy clip of their choice for the eustress condition and the opening 20 minutes of Saving Private Ryan for the distress condition, with a one‑week washout between sessions. Blood pressure was recorded, and blood samples were taken before and after each viewing.
The distressing war footage produced no meaningful change in appetite hormones. In contrast, the funny video led to a drop in leptin (the satiety hormone) and a rise in ghrelin (the hunger hormone), mirroring hormonal shifts seen after moderate exercise. Dr. Berk cautioned that laughter doesn’t magically make you ravenous, but the hormonal response could be useful for patients who struggle to stimulate appetite through physical activity.
3 The Best Medicine
What if a zap to the brain could trigger giggles and calm anxiety at the same time? A 2019 study published in The Journal of Clinical Investigation reported that electrical stimulation of the cingulum bundle reliably induced laughter while also soothing participants.
During routine brain‑mapping for epilepsy surgery, researchers applied brief electrical pulses to the cingulum bundle of a 23‑year‑old woman. The stimulation produced uncontrollable laughter, wide‑grinned smiles, and a pronounced sense of relaxation, all without impairing cognition. The team replicated the effect in two additional patients.
Co‑author Dr. Jon T. Willie suggested that the cingulum bundle’s extensive connections to emotion‑regulation centers explain the dual impact on mirth and anxiety. While the current method requires invasive electrodes, the findings hint at future, less‑invasive therapies for depression, anxiety, chronic pain, and perhaps a more pleasant experience for awake brain surgeries.
2 The Laughie
Selfies have taken over the internet; now a new trend called the “Laughie” might be the next big thing. Researchers at the University of Derby investigated whether recording one’s own joyous laughter and replaying it could boost well‑being.
Twenty‑one participants ranging from 25 to 93 years old created a one‑minute “Laughie” and listened to it three times daily for a week. In 89 % of the playback sessions, listeners ended up laughing for most of the duration.
Nineteen participants reported heightened well‑being after the week, with scores on the World Health Organization Well‑Being Index climbing by 16 %. Those who started with lower baseline scores experienced the greatest gains, suggesting that even personal laughter can be contagious and therapeutic.
1 Risible Rats
Fact: Rats laugh
Laughter isn’t a purely human pastime. Researchers have observed giggle‑like vocalizations in rats when they’re tickled, a sound that sits above the range of human hearing.
A 2000 study showed that tickled rats emitted these high‑frequency chirps, and some even followed the experimenter’s hand, clearly enjoying the interaction. In a 2016 follow‑up at Berlin’s Bernstein Center for Computational Neuroscience, scientists compared vigorous tickling, gentle tickling, and a chase game. Both vigorous tickling and the chase elicited the happy chirps, and electrophysiological recordings revealed heightened activity in the rats’ somatosensory cortices.
Electrical stimulation of the somatosensory region also prompted the laughing sounds, though it remains uncertain whether the rats truly felt pleasure. When the rodents were placed on a brightly lit pedestal—an anxiety‑inducing scenario—their chirps and cortical activity diminished, confirming that the vocalizations reflect genuine positive affect rather than alarm.
10 Fascinating Scientific Insights About Laughter
These ten fascinating scientific discoveries about laughter illuminate how this simple act weaves through biology, culture, and technology, proving that a chuckle is far more powerful than we ever imagined.