Basic Emotions: Why Do We Need Laughter?

Laughter is a universal phenomenon found in every person, regardless of age, culture, or nationality. It brings us together, allows us to experience joy, and improves our well-being. But why do we laugh, and what benefits does it bring? In this article, we explore the role of laughter in our lives and try to understand why it is so important for us to laugh.

What Is Laughter?

Laughter is a physiological response to humor, consisting of two parts: a set of gestures and the production of sound. When we laugh, our brain makes us perform both actions at the same time. Genuine laughter causes changes throughout the body, even in the muscles of our arms, legs, and torso.

Physiologically, laughter involves the contraction of fifteen facial muscles and stimulation of the major zygomatic muscle. At the same time, our respiratory system is disrupted—this is why, when we laugh too hard, we start to gasp for air and swallow, because the epiglottis partially closes the larynx, making airflow irregular. In extreme cases, our tear ducts are activated: as our mouth opens and closes and our body struggles for oxygen, our face becomes moist and often flushed. The sounds that accompany this strange behavior range from quiet giggles to uncontrollable laughter.

Research by behavioral neurobiologist and laughter expert Robert Provine shows that all human laughter is a variation of a basic sound pattern, consisting of short vowel notes repeated every 210 milliseconds. Provine also suggests that humans have a “detector” that responds to laughter, activating other neural circuits in the brain, which in turn trigger even more laughter. This explains why laughter is so contagious.

Why Do We Laugh?

Philosopher John Morreall believes that the first person laughed as a gesture of collective relief after a danger had passed. Since the relaxation that comes from a bout of laughter suppresses the biological “fight or flight” response, laughter can also signal trust in one’s companions.

Laughter acts as a kind of social signal—people are 30 times more likely to laugh in social settings than when alone. Many researchers believe that laughter is linked to forming and strengthening human bonds—this feedback loop of laughter and increased attachment, combined with the general desire not to stand out from the group, may be another reason why laughter is often contagious.

Studies have also shown that dominant personalities use humor more often than their subordinates. In such cases, controlling laughter within a group may become a way to assert authority by managing the emotional climate. So, like much of human behavior, laughter likely evolved to influence the behavior of others: for example, in embarrassing or threatening situations, laughter can serve as a conciliatory gesture or a way to deflect anger.

How Do We Laugh?

The physiological study of laughter even has its own name—gelotology. We already know that certain parts of the brain are responsible for specific human functions (for example, emotional reactions are a function of the frontal lobe), but various areas of the brain are involved in producing laughter.

Researchers have tracked the pattern of brain waves that respond to humorous material. In one experiment, subjects were connected to an electroencephalograph (EEG), and every time they laughed, the brain produced the same electrical pattern. Within four-tenths of a second after encountering something potentially funny, an electrical wave passed through the cerebral cortex, the brain’s largest part. If the wave took on a negative charge, it led to laughter, but if it remained positive, there was no response.

During the experiment, researchers observed the following specific reactions:

• The left side of the cortex (the layer of cells covering the entire surface of the forebrain) analyzed the words and structure of the joke.
• The large frontal lobe, which is involved in social emotional reactions, became very active.
• The right hemisphere of the cortex performed the intellectual analysis needed to “get” the joke.
• Then, brain wave activity spread to the sensory processing area of the occipital lobe (the area at the back of the head that processes visual signals).
• Finally, stimulation of the motor areas triggered the physical response to the joke.

Importantly, this pathway is different from what happens with emotional reactions—emotional responses seem to be limited to certain areas of the brain, while laughter is produced by a chain of events that pass through many brain regions. This means that damage to any of these areas can impair one’s sense of humor and response to humor.

If we look more closely at the brain areas associated with laughter, the main one is the limbic system—a network of structures beneath the cerebral cortex that controls certain behaviors necessary for all mammals (like finding food and self-preservation).

Although the structures in this highly developed part of the brain are interconnected, studies have shown that the amygdala, a small almond-shaped structure deep inside the brain, and the hippocampus, a tiny seahorse-shaped structure, are the main areas involved in emotions. The amygdala connects to the hippocampus and the medial dorsal nucleus of the thalamus, and these connections allow it to play a key role in mediating and controlling basic expressions such as friendship, love, attachment, and mood. The hypothalamus, especially its central part, has been identified as the main source of loud, uncontrollable laughter.

Why Do We Laugh?

We’ve all heard the saying “Laughter is the best medicine,” and for good reason: there is convincing evidence that laughter can actually improve health and help fight disease by balancing all components of the immune system.

Laughter reduces the level of certain stress hormones, particularly cortisol. It acts as a safety valve, shutting off the flow of hormones that are released in our bodies when we experience stress, anger, or hostility. Stress hormones suppress the immune system, increase the number of platelets in the blood (which can cause artery blockages), and raise blood pressure. When we laugh, the number of natural killer cells that destroy tumors and viruses increases, as does the amount of gamma interferon (a disease-fighting protein), T-lymphocytes (a key part of the immune response), and B-lymphocytes (which produce antibodies that destroy disease).

Laughter can also cause hiccups and coughing, which clear the airways by removing mucus plugs. It increases the concentration of immunoglobulin A in saliva, which protects against infectious organisms entering through the respiratory tract. When we laugh, blood pressure drops, blood flow in the vessels increases, and the blood becomes more oxygenated, all of which further promote healing. Laughter also exercises the diaphragm and muscles of the abdomen, respiratory tract, face, legs, and back.

As for psychological benefits, people often hold on to negative emotions like anger, sadness, and fear instead of expressing them—laughter provides a harmless way to release these emotions.