Sternutation Is Another Word For What

Sternutation, a term you might not hear every day, is actually the medical term for something quite common: sneezing. Sneezing, or sternutation, is a sudden, forceful expulsion of air through the nose and mouth. It's a reflex action, meaning it happens automatically in response to an irritation. This article delves into the science of sneezing, exploring the causes, mechanisms, and even the quirky myths and facts surrounding this universal human experience.

The Sneezing Reflex: A Deep Dive

What Triggers a Sneeze?

Sneezing is primarily a protective mechanism. It's the body's way of clearing irritants from the nasal passages. These irritants can range from:

Allergens: Pollen, dust mites, pet dander, and mold spores are common triggers for allergic sneezes.
Irritants: Smoke, pollution, perfumes, and strong odors can irritate the nasal lining, leading to a sneeze.
Infections: Viral infections like the common cold or flu often cause sneezing as the body tries to expel the virus.
Physical Stimuli: Sudden exposure to bright light (the photic sneeze reflex), or even a tickle inside the nose, can trigger a sneeze.
Temperature Changes: Sudden shifts in temperature, such as stepping from a warm building into cold air, can also initiate sneezing.

The Mechanics of a Sneeze

The process of sneezing involves a complex series of coordinated actions:

Irritation Detection: Sensory nerves in the nasal passages detect the presence of an irritant.
Signal Transmission: These nerves send a signal to the brainstem, the control center for reflexes.
Reflex Activation: The brainstem triggers a cascade of events, including:
- Deep inhalation: Taking in a large volume of air.
- Closure of the eyes: A protective measure to prevent irritants from entering the eyes.
- Contraction of chest muscles: These muscles forcefully compress the lungs.
- Closure of the back of the throat: This directs the air flow through the nose and mouth.
- Forceful expulsion: The air is rapidly expelled, carrying mucus, saliva, and irritants with it.

Why Do We Close Our Eyes When We Sneeze?

The common belief that your eyes will pop out if you don't close them during a sneeze is a myth. However, there's a real reason why we instinctively close our eyes. The brainstem, when triggering the sneeze reflex, also activates the muscles around the eyes. This is likely a protective mechanism to prevent irritants and infectious agents from entering the eyes during the forceful expulsion.

Types of Sneezes and What They Might Indicate

While sneezing is a normal bodily function, different types of sneezes can sometimes indicate underlying health issues:

Allergic Sneezing: Characterized by repetitive sneezing, often accompanied by a runny nose, itchy eyes, and nasal congestion. It's triggered by allergens and is often seasonal.
Infectious Sneezing: This type of sneezing is associated with viral or bacterial infections. It's often accompanied by other symptoms like fever, cough, sore throat, and body aches. The sneezes are usually more forceful and frequent as the body tries to expel the pathogens.
Photic Sneezing: Also known as the photic sneeze reflex or sun sneeze, this type of sneezing is triggered by sudden exposure to bright light. It's a hereditary condition affecting a significant portion of the population.
Gustatory Rhinitis: Sneezing triggered by eating, particularly spicy foods. It's thought to be caused by the stimulation of nerves in the nasal passages.
Psychogenic Sneezing: In rare cases, sneezing can be triggered by psychological factors like stress or anxiety. This is a less common and more complex phenomenon.

The Science Behind Common Sneeze-Related Questions

How Far Does a Sneeze Travel?

Sneezes are powerful expulsions that can propel droplets containing saliva, mucus, and potentially infectious agents over a considerable distance. Research has shown that sneeze droplets can travel up to 20-30 feet, depending on the force of the sneeze and environmental factors like humidity and air currents. This is why covering your mouth and nose when you sneeze is crucial to prevent the spread of germs.

What is the Speed of a Sneeze?

The commonly cited figure of 100 miles per hour for the speed of a sneeze is likely an exaggeration. While sneezes are certainly fast, more recent research suggests that the actual speed is closer to 30-40 miles per hour. Regardless of the exact speed, the force of a sneeze is significant, highlighting the importance of proper sneeze etiquette.

Is it Dangerous to Hold in a Sneeze?

While it might seem harmless to suppress a sneeze, doing so can actually be risky. Holding in a sneeze can increase pressure in the respiratory system, potentially leading to:

Ruptured blood vessels: The increased pressure can cause small blood vessels in the eyes, nose, or even the brain to rupture.
Ear damage: The pressure can also force air into the Eustachian tube, which connects the middle ear to the back of the throat, potentially causing ear pain or even a ruptured eardrum.
Muscle strain: The forceful contraction of muscles during a sneeze can lead to muscle strain in the chest or diaphragm if the sneeze is suppressed.

Therefore, it's generally best to allow a sneeze to occur naturally, while covering your mouth and nose to prevent the spread of germs.

Photic Sneeze Reflex: Why Does Light Make Us Sneeze?

The photic sneeze reflex, also known as sun sneezing, is a fascinating phenomenon that affects an estimated 18-35% of the population. Individuals with this reflex sneeze when suddenly exposed to bright light, particularly sunlight. The exact mechanism behind this reflex is not fully understood, but the most widely accepted theory involves a "crossed-wiring" effect in the brain.

Theories Behind Photic Sneeze Reflex

The Optic Nerve Theory: This theory suggests that the optic nerve, which transmits visual information from the eyes to the brain, is located close to the trigeminal nerve, which controls sneezing. When exposed to bright light, the optic nerve may overstimulate, sending a signal that "crosses over" to the trigeminal nerve, triggering a sneeze.
Parasympathetic Nervous System Theory: Another theory proposes that the photic sneeze reflex is related to the parasympathetic nervous system, which controls involuntary functions like digestion and salivation. Bright light may stimulate the parasympathetic nervous system, leading to a cascade of events that ultimately result in a sneeze.

Is Photic Sneeze Reflex Dangerous?

The photic sneeze reflex is generally harmless, although it can be inconvenient or even dangerous in certain situations. For example, a driver who sneezes uncontrollably when exiting a tunnel into bright sunlight could briefly lose control of their vehicle. If you experience this reflex, it's important to be aware of potential triggers and take precautions when necessary, such as wearing sunglasses or slowing down when transitioning from dark to bright environments.

Sneezing Etiquette: How to Sneeze Respectfully

Sneezing is a natural bodily function, but it's important to practice proper etiquette to prevent the spread of germs and show consideration for others. Here are some guidelines:

Cover Your Mouth and Nose: Use a tissue to cover your mouth and nose when you sneeze. If a tissue is not available, sneeze into the crook of your elbow rather than your hands.
Dispose of Tissues Properly: Discard used tissues in a wastebasket immediately after sneezing.
Wash Your Hands: Wash your hands thoroughly with soap and water after sneezing, especially if you used your hands to cover your mouth and nose.
Maintain Distance: If you're feeling unwell and sneezing frequently, try to maintain a distance from others to minimize the risk of spreading germs.
Avoid Touching Your Face: Avoid touching your eyes, nose, and mouth, as this can transfer germs from your hands to your face.

Cultural Beliefs and Superstitions About Sneezing

Sneezing has been associated with various beliefs and superstitions throughout history and across different cultures. Some examples include:

Bless You: The practice of saying "bless you" after someone sneezes dates back to ancient times. One theory suggests that it originated during the bubonic plague, when sneezing was a symptom of the disease. Saying "bless you" was thought to offer protection against the plague. Another theory is that people believed the heart stopped momentarily during a sneeze, and saying "bless you" was a way to wish the person back to life.
Good or Bad Luck: In some cultures, sneezing is considered a sign of good luck, while in others it's seen as a bad omen. For example, in ancient Rome, sneezing to the right was considered lucky, while sneezing to the left was unlucky.
Truth or Falsehood: Some cultures believe that sneezing confirms the truth of what was just said. If someone sneezes while you're speaking, it means that what you're saying is true.
Spiritual Significance: In some spiritual traditions, sneezing is believed to be a sign of spiritual cleansing or the expulsion of negative energy.

When to See a Doctor About Sneezing

While sneezing is usually a harmless and self-limiting condition, there are certain situations when it's important to seek medical attention:

Persistent Sneezing: If you experience persistent sneezing that lasts for several weeks or months, it could be a sign of an underlying allergy or other medical condition.
Sneezing Accompanied by Other Symptoms: If your sneezing is accompanied by other symptoms like fever, cough, chest pain, difficulty breathing, or bloody mucus, it could indicate a more serious respiratory infection.
Sneezing After an Injury: If you start sneezing after a head injury or nasal trauma, it's important to see a doctor to rule out any complications.
Sneezing Interfering with Daily Life: If your sneezing is severe enough to interfere with your daily activities, such as sleep, work, or school, it's worth seeking medical advice.

A doctor can help determine the cause of your sneezing and recommend appropriate treatment options, such as antihistamines for allergies, decongestants for nasal congestion, or antibiotics for bacterial infections.

Conclusion: The Underestimated Importance of Sternutation

So, sternutation is simply another word for the common act of sneezing. While it might seem like a trivial bodily function, sneezing plays a crucial role in protecting the respiratory system from irritants and infections. Understanding the mechanics of sneezing, the various types of sneezes, and proper sneeze etiquette can help us stay healthy and prevent the spread of germs. From the photic sneeze reflex to cultural beliefs surrounding sneezing, there's more to this everyday phenomenon than meets the eye (or nose!). So next time you feel a sneeze coming on, remember the science behind it, cover your mouth and nose, and appreciate the body's amazing ability to protect itself.