news&views Autumn 2020 | Page 46

Tears in Our Eyes Jock Mackenzie, Article | Avery Sosnowski, Artwork Someone said, “You don’t know what you don’t know.” My problem has often been that I thought I knew — but found out I didn’t. I guess my vision was blurred. And like a word association game I used to play with my Language Arts students to get them to come up with ideas, vision made me think of eyes, eyes made me think of tears, and tears made me think of where tears come from. I thought tears originated in the corners of my eyes. Wrong. And so, this article: a series of questions and answers. Where do tears come from? Tears come from above our eyes, from the lacrimal gland, which has a series of ducts that secrete tears down into our eyes. Are there different kinds of tears? We have three main types of tears. Most of us have a good supply of basal tears. These are secreted from above the eye, the eyelid blinks and distributes them across the eye’s surface, and, in turn, they perform three more purposes: lubrication, protection from debris, and nourishment. Reflex tears form when they’re needed — when you encounter smoke or cut an onion or get too close to Auntie Irene and her cloying perfume. They may also appear in reaction to bright light or particularly spicy food. Emotional tears, also known as psychic tears, are exactly what the name suggests. We create tears as an emotional response: joy, sadness, anger, mourning, pain, speeding tickets. Emotional tears have been called our body’s “stabilizer” because, like slower breathing and an increased heart rate, they help to steady our body’s reactions and return it to its normal state. What are tears made of? Tears come in three layers: oily (outer), watery (middle), and mucus (inner). In order, these layers make the tear surface smooth and keep tears from drying too quickly, clean the eye and wash away unwanted particles, and help spread the watery layer and keep it moist. Why are tears salty? Tears are salty for the same reason that sweat is salty. Bodily fluids contain a variety of substances. A major one is sodium. When our body secretes either tears or perspiration, and we taste it, we notice this concentration of sodium. (Table salt is 40% sodium and 60% chloride; tears are said to have two or three grains of salt per drop.) Where do tears go? Tears exit the eye through two openings (tiny holes called puncta), one in each of the inner corners of the eyelids. They then flow into a canal that carries them to the lacrimal sac which is in the nose. If you have too many tears, like a spring flood, they jam the canal system, overflow the banks, and run down your cheeks. The tears that do make it into 46 | arta.net