Laughing is an action that can be looked at physiologically, psychologically, and socially. Physiologically, we know that we laugh because our bodies release a physical reaction from our respiratory system that lets out an auditory sound similar to “ha-ha” or “he-he” (Stearns, 1972). Psychologically, we often laugh because we are confronted with positive emotions, such as joy or amusement. However, laughing may also be a psychological response when surprised or embarrassed (Gregory, 2013). From a social context and human behavior standpoint, laughter is often triggered by positive interactions with other humans, which can offer bonding, emotional intimacy, and acceptance from others (Scott et al., 2014). ​

Laughter research suggests that the evolution of human laughter began more than ten million years ago (Ross, Owren, & Zimmermann, 2009). However, as psychological and scientific research has advanced, particularly in the past century, gelotology, or the study of laughter, is still growing.

Here are some historical tidbits about laughter dating back to the late 1800s and early 1900s.

●        In 1875, scientist Herbert Spencer theorized that laughter was a physiological reaction caused by the evocation of happy emotions and muscular excitement in our speech organs (Spencer, 1875).

●        From a biological standpoint, one researcher conveyed that laughter interrupts our body’s rhythmic flow, akin to crying, sneezing, or coughing (Sully, 1902).

●        In their book about the psychology of relaxation, one philosopher authored that laughter was a form of relaxation and offered relief from a tense thought or situation (Patrick, 1916).

●        One researcher looked into the correlation between laughter and safety and found that people usually don’t laugh out of joy unless they are in a safe environment with people they feel calm (Hayworth, 1928).

●        Research from 1933 suggested that laughter is the primary reaction to expressing euphoric feelings. This research also theorized that some happy stimuli cause infant laughter and can affirm the baby’s well-being to their parents (Piddington, 1933). ​

Let’s take a look at some more science about laughter. Here are a few facts to get our laughter listicle started:

●        Laughter in other animals. Did you know humans are not the only species who can laugh? A recent study showed that nearly 65 different species also have their form of laughter. A researcher at UCLA studies the sounds of other animals, and while they may not sound precisely like human laughter, they do something similar to laughter. These are called play vocalizations. These vocal sounds emitted from the animals in the study show that when animals are tickled, they may produce laughter-like audio (Winkler & Bryant, 2021).

●        Laughter was a survival mechanism. Anthropologists and psychologists have argued that laughing in early humans was to signal to other group members that they were safe from harm. Think back to the hunter-gatherer days when life was often nomadic, and environments around groups of humans were constantly changing. Perhaps they lived among animals that preyed on humans or in areas that posed environmental threats to safety. Evolutionary studies later expanded on the idea that laughter was emitted during relaxation, which was why our modern-day human brains laugh when we are amused, relaxed, or find something funny (Provine, 2001).

●        Laughter is contagious. Have you ever been in a room, looked across the aisle, found someone yawning, and then immediately felt the need to yawn yourself? It turns out that just like yawning, laughter is contagious. Studies suggest that you're more likely to laugh when you hear someone else laugh.

Laughter is also great for our mental and physical health. Check out these facts about laughter and health below (Martin, 2002).

●        Laughter and Endorphins. When we laugh, our body releases endorphins, and endorphins can release dopamine. Dopamine is a neurotransmitter (or happiness hormone) that can help improve our mood.

●        Laughter and Tension. We all know life comes with its stressors; sometimes, we can hold that stress in our bodies. If you feel your shoulders feeling heavy or your lower back aching, it could be because stress can lead to muscle tension. However, research suggests that laughter can alleviate tension and help relax our muscles.

●        Laughter and Heart Health. Laughing often can improve cardiovascular health by increasing blood flow to the heart. When our cardiovascular health improves, we can also lower the risk of heart disease and heart attack (which is just one factor of heart health). ​

In Summary

Even though laughter has most likely been a daily occurrence in our lives since we were little infants in diapers, hopefully, you learned something new today about laughing.

References

●        Gregory, J. C. (2013). The nature of laughter. Routledge.

●        Hayworth, D. (1928). The social origin and function of laughter. Psychological Review, 35(5), 367–384.

●        Martin, R. A. (2002). Is laughter the best medicine? Humor, laughter, and physical health. Current directions in psychological science, 11(6), 216-220.

●        Patrick, G. T. W. (1916). The psychology of relaxation. Houghton Mifflin.

●        Piddington, R. (1933). The psychology of laughter. A study in social adaptation. Figurehead.

●        Provine, R. R. (2001). Laughter: A scientific investigation. Penguin.

●        Scott, S. K., Lavan, N., Chen, S., & McGettigan, C. (2014). The social life of laughter. Trends in cognitive sciences, 18(12), 618-620.

●        Spencer, H. (1875). The physiology of laughter. In H. Spencer, Illustrations of universal progress: A series of discussions (pp. 194–209). D Appleton & Company.

●        Stearns, F. R. (1972). Laughing: Physiology, pathophysiology, psychology, pathopsychology, and development.

●        Sully, J. (1902). An essay on laughter: Its forms, causes, development, and value. Longmans, Green, and Company.

●        Winkler, S. L., & Bryant, G. A. (2021). Play vocalizations and human laughter: a comparative review. Bioacoustics, 30(5), 499-526.