Buzz
Laughter is one of the most universally shared human experiences, sitting just behind death but undoubtedly above taxes. It serves as a classic sign of joy, amusement, and connection, echoing across the globe, and most of us can probably agree that a hearty laugh is something we all enjoy from time to time.
People have a deep fondness for laughter, and some scientists are equally passionate about studying it. After all, why not? It's an endlessly intriguing subject. Often called the best medicine, though there are numerous anecdotal stories of people passing away while laughing. Here, we present just a few scientific findings on one of life’s more delightful activities.
10. Babies and Chimpanzees
Fact: Babies Laugh Just Like Chimpanzees
Chimpanzees are our closest living relatives, so it’s no surprise that we share a lot in common with them. A 2018 study even found that one of those similarities is how we laugh, at least when it comes to infants.
A group of three psychologists and a phonetician from various European universities examined the laughter of 44 babies, ranging in age from three to 18 months. They did this by gathering video clips of babies laughing, which are plentiful online. A key focus of the study was how much of the laugh occurred during inhalation versus exhalation. To assess this, 102 psychology students were asked to evaluate the clips.
The results showed that younger babies laughed both during inhalation and exhalation, similar to chimpanzees. On the other hand, babies on the older end of the age spectrum mostly laughed during exhalation, much like adult humans. This change in laughter pattern wasn’t tied to specific developmental stages but instead seemed to develop gradually with age.
The researchers acknowledged that these conclusions were drawn by non-experts but planned to have additional phoneticians review the clips. Dr. Disa Sauter, who led the study, pointed out that there is no clear explanation as to why humans typically laugh on exhalation while other primates do not. It could be attributed to humans’ superior vocal control. Future research will explore whether the inhalation/exhalation ratio is linked to the cause of laughter (which also changes as babies age) and if similar changes occur in other types of vocalizations.
9. The Phenomenon of Fake Laughter
Fact: We Can Identify Fake Laughter, No Matter Our Background
Sometimes, a laugh is the result of a genuinely hilarious moment that leaves you crying with laughter, and sometimes it's a mere act of politeness. Whether it's to charm your boss or to gracefully exit a cringeworthy conversation, many of us have let out a fake chuckle at some point. Unfortunately, these forced laughs may not be as convincing as we think.
In 2018, Dr. Greg Bryant of UCLA published a study showing that the ability to recognize authentic laughter exists across cultures. Bryant and his team tested this with 884 individuals from 21 countries across six continents. Participants listened to recordings of both spontaneous laughter from English-language conversations and contrived laughs from people asked to laugh on cue.
No matter their cultural background, listeners were able to distinguish real laughs from fake ones at a rate higher than chance. At the lowest rate, Samoans identified laughs correctly 56% of the time, while Japanese listeners were accurate 69% of the time. Dr. Bryant also highlighted that real and fake laughter have distinct sonic qualities, with fake laughter often sounding more like speech than genuine laughter.
8. The Phenomenon of Canned Laughter
Fact: Canned Laughter is Effective
When it comes to fake laughter, let's not forget about the laugh tracks in sitcoms. While they're not as commonly used as they once were, they haven't completely disappeared. Nowadays, many critics wish these laugh recordings would fade into obscurity. The irony is that, despite the complaints, canned laughter may actually enhance the comedic effect.
In 2019, *Current Biology* published a study by Dr. Sophie Scott of University College London that investigated the impact of recorded laugh tracks on one of comedy's greatest foes: dad jokes. Here are four examples used in the study:
*What state has the smallest drinks? Mini-soda! What does a dinosaur use to pay the bills? Tyrannosaurus cheques! What’s orange and sounds like a parrot? A carrot! What do you call a man with a spade on his head? Dug!*
As you can tell, these jokes are far from impressive. Seventy-two participants were exposed to 40 of these jokes, followed by either no laughter, fake laughter, or genuine laughter. The participants then rated how funny they found the jokes on a scale of one to seven. The results revealed that adding laughter improved the ratings by about 10% with fake laughter and by 15 to 20% with real laughter.
7. Immunity
Fact: Laughter and the Immune System
In 2003, a study investigated how laughter affects the activity of natural killer cells (NK cells), which are crucial to the immune system. The researchers selected 33 healthy adult women from rural Midwest areas. Participants in the experimental group watched a comedic video, while those in the control group watched a tourism video.
The women in the experimental group had the option to choose between stand-up performances by Bill Cosby, Tim Allen, or Robin Williams. Most opted for Cosby (this was 2003, after all). The humor level of the videos was evaluated using the Humor Response Scale (HRS) created specifically for the study. Afterward, both groups’ NK cell activity was measured.
The results showed that simply watching a comedic video didn't lead to a statistically significant rise in NK cell activity. However, women in the comedy group who rated the videos highly on the HRS saw a significant positive correlation between their HRS scores and NK cell activity. The effect was most noticeable for those with HRS scores of 25 or higher. Interestingly, women who watched the comedy but didn't find it funny experienced a decrease in NK cell activity.
6. Dominance
Fact: Dominance and Laughter
Dr. Christopher Oveis from UC San Diego conducted research revealing that individuals in higher-status positions laugh differently from those with less power, and others are quick to pick up on these subtle cues.
In 2014, he aimed to verify whether status influences laughter. Earlier studies had already suggested that power affects the acoustic qualities of speech. This time, videos of four fraternity brothers (two new members and two veterans) were shown to various observer groups who were unaware of the study's purpose. In these videos, each brother took turns being teased by the others. Their laughter was then assessed for dominance, along with characteristics such as loudness, pitch, and variation. Laughter from the more dominant individuals was found to be louder, higher-pitched, and more variable in tone. New pledges only exhibited dominant laughter when they were the ones doing the teasing, while the experienced fraternity brothers laughed dominantly in all situations.
A follow-up study in 2016 involved 51 students listening to 20 recordings of the fraternity members’ laughs. The students were asked to rate the perceived social status of the laugher. As expected, laughs that sounded dominant were associated with higher status. This was true even when the dominant-sounding laughter came from a new pledge, suggesting that one could appear more powerful through their laugh. Conversely, even if an established frat member emitted a submissive-sounding laugh, they were still perceived as having a high status.
5. Psychopathy
Fact: Is Immunity to Laughter a Warning Sign of Psychopathy?
Much research has focused on which childhood behaviors might predict psychopathy in later life, including how a child responds to laughter. Laughter is often called contagious, and studies show that just hearing laughter can trigger the brain to ready the facial muscles to laugh. Interestingly, boys who are at risk of developing psychopathy might not be susceptible to this ‘contagion’ of laughter.
In 2017, researchers from University College London conducted a study involving 92 boys aged 11 to 16. Thirty of the boys were considered ‘normal’ and served as a control group, while 62 were flagged as potentially showing signs of psychopathy. These 62 were further divided based on whether they exhibited ‘callous-unemotional traits’ in addition to disruptive behaviors. The boys underwent MRIs while listening to authentic laughter, fake laughter, and crying sounds. They were also asked to rate how much each sound evoked the associated emotions.
The MRIs revealed that all the boys’ brains reacted to genuine laughter. However, those with both disruptive behavior and callous-unemotional traits exhibited less brain activity in the supplementary motor area and anterior insula, regions linked to joining in laughter and empathizing with others. A lesser, but still notable, difference was observed in the disruptive boys who did not have the callous-unemotional traits. Dr. Essi Viding, the study leader, remarked that it’s unclear whether the diminished response to laughter is a result of the boys’ behavior or whether it contributes to the behavior, but she emphasized that the results merited further investigation.
4. Appetite
Fact: Laughter and Appetite
In 2010, Dr. Lee S. Berk, Dr. Jerry Petrofsky, and colleagues conducted a study to investigate how 'mirthful laughter,' a form of eustress, influences hormones that control appetite. They compared the effects of laughter with those produced by distress.
Fourteen participants were shown a comedic video of their choice during the eustress portion of the study and the first 20 minutes of *Saving Private Ryan* during the distress part. Each participant watched both videos a week apart. Blood pressure and blood samples were taken before and after each video.
The distressing video showed no significant change in appetite hormone levels, and it didn’t seem to affect anyone's hunger. However, the funny video caused a decrease in leptin and an increase in ghrelin, similar to what occurs after moderate exercise. Dr. Berk clarified that the study didn’t claim laughter directly increases hunger (though some media outlets reported it as such). The results were more valuable for their potential applications in helping patients who cannot use exercise to stimulate their appetites.
3. Risible Rats
Fact: Rats laugh
Laughter isn't exclusive to humans, as demonstrated by the earlier comparison of infant laughter to that of chimpanzees. Another unexpected source of laughter can be found in rats.
A 2000 study revealed that rats emitted sounds similar to laughter when tickled, which are usually outside of the human hearing range. Some rats even seemed to enjoy being tickled, following the hand of the researcher who did it.
In 2016, researchers at the Bernstein Center for Computational Neuroscience in Berlin tickled rats again. They tested the rats’ responses to various forms of tickling and a chase game. Both vigorous tickling and the chase game triggered laughter-like sounds in the rats. Electrodes placed on the rats’ brains showed that all three activities stimulated the somatosensory cortices. Interestingly, electrical stimulation of this brain area also induced laughter, though it’s unclear if the rats were genuinely enjoying it.
Interestingly, when the rats were subjected to anxiety (by placing them on a high pedestal under bright lights), both their cheerful vocalizations and the brain activity in the somatosensory cortex during tickling significantly decreased. This result reinforced the idea that their giggling and brain response in the previous scenarios weren't indicators of distress.
2. The Laughie
Fact: The Laughie... Is it the new selfie?
Whether you love them or not, selfies are now a permanent part of our culture. Millions of people around the globe are snapping them with their smartphones and sharing them on social media, often stirring a variety of reactions. Some see selfies as a symptom of societal decay, while others view them as a method of self-expression and even therapy. But what about the Laughie?
In a 2019 study, Freda Gonot Schoupinsky, a graduate student at the University of Derby under the guidance of Dr. Gulcan Garip, researched the effects of laughter on well-being. This particular study explored the Laughie, a recording of one’s own joyful laughter on a smartphone, which can be replayed whenever needed.
A group of twenty-one participants, ranging from 25 to 93 years old, created their own one-minute Laughies and played them back three times a day for a week. During 89% of these sessions, the participants found themselves laughing along with the playback. By the end of the week, nineteen participants reported feeling better. Their scores on the World Health Organization Well-Being Index had increased by 16%, with the greatest improvement seen in those who started with lower scores. It appears that laughter, even your own, has a contagious effect.
1. The Best Medicine
Fact: Making The Patient Laugh, Literally
A study published in The Journal of Clinical Investigation in 2019 found that electrically stimulating a specific area of the brain could reliably induce laughter while also reducing anxiety. While previous studies have shown that stimulating other parts of the brain can cause laughter, this was the first instance where a decrease in anxiety was also observed. The research team was conducting brain mapping on epilepsy patients, using electrodes placed on the brain to stimulate different regions and investigate the origin of seizures.
During the study, while working with a 23-year-old woman, the researchers found that stimulating her cingulum bundle consistently triggered uncontrollable laughter, smiling, and a sense of calm and relaxation. Her mood improved, and there was no impairment in her cognitive functions. After these findings, the team tested the same procedure on two other patients and achieved identical results.
Dr. Jon T. Willie, one of the study's co-authors, suggested that the observed effect was linked to the cingulum bundle's connections with other brain areas involved in emotion regulation. This discovery could have profound implications for treatment. It offers the potential to ease the experience of brain surgery where patients must remain conscious. In the future, this approach might lead to therapies for depression, anxiety, and chronic pain. While currently, stimulating the cingulum bundle requires invasive surgery, advancements in medical technology may soon allow for a less invasive method.
