Point of View

## Confusing Science Vocabulary: When Negative Is Positive!

I have applied lessons to my teaching of college students that I learned outside the academy. An important lesson is that traditional vocabulary affects the efficiency and effectiveness of our science teaching. Too often, the words used actually get in the way of a beginner’s understanding of science.

One lesson I learned while watching the confusion of 5-year-olds playing baseball. “Hit” has two distinct meanings; in the first meaning, the bat hits the ball when the two touch. Not every “hit” in this sense is a hit because the second meaning also requires that the batter gets to first base safely.

The word “negative” has several meanings. Negative consequences are not desirable. In contrast, negative feedback loops in physiology are usually desirable. However, many beginning physiology students assume that negative feedback loops are not desirable, just like a negative bank account is not desirable. In contrast, there are many times when a negative feedback loop keeping blood ions and hormones constant is desirable, just as often keeping room temperature constant is desirable. I now start this section using the terms stable feedback loops and spiraling feedback loops.

Another lesson comes from jokes my dad told about history exam questions: When was the War of 1812? Who fought in the Spanish-American War? Plain language questions often have easy answers.

In physiology we use the hydraulic analogy of Ohm’s law: water flow = water pressure / water resistance.

Wouldn’t the students understand it better if we stated this as:
amount flowing =
force to cause flow x
ease of flow?

Physiology students memorize:
cardiac output =
stroke volume x heart rate.

But: cardiac output per minute = cardiac output per beat x beats per minute is the same. The latter makes problems nearly as easy as those history questions.

Many jargon words in science are based on Latin and Greek roots. Yigit, a Turkish exchange student, was puzzled to discover that my son spent 6 weeks in middle school math class learning the terms for polygons, such as pentagon, which is Greek for 5-angled figure. In Turkish, the word for pentagon is the Turkish phrase “5 angled.” So when Yigit was studying polygons in Turkey, covering the names took one day; if the child could count, the child could name the figure. Lesson completed in one day, not six weeks.

I value students learning another language, but then it ought to be taught as a language; it doesn’t make sense to me that we think that mastering Latin and Greek suffixes has anything to do with understanding math concepts.

I wonder how much time I have spent using jargon in my classes, the equivalent of spending time in math class teaching children how to say “5 angled” in Greek. And when we test them, we make them think they have learned concepts, when in fact, they have merely learned words in another language. Furthermore, we don’t even point this out to them.

Does saying a patient has hypertension really convey more than saying the patient has high blood pressure? Actually, you can see that hypertension conveys less than high blood pressure as hypertension does not explicitly tell us what pressure is being discussed.

I learned yet another lesson while working in a brick factory during college. A brick kiln loader was used to transport bricks into the oven. The driver stood at the back. The steering wheel controlled the back wheels. When the steering wheel turned to the right, the brick kiln loader turned to the left. The clutch and the brake were operated by the same pedal; the driver stepped down on the clutch to move forward. The driver released the pedal to engage the brake. When I was a new brick kiln loader driver, I almost caused a serious injury. While I was driving the loader, a person suddenly appeared on my left. I instinctively turned the wheel to the right, making the loader head straight toward the person. I panicked and stomped down on the pedal but that only increased my speed. Fortunately, I then remembered to lift my foot and turn the wheel to the left. The lesson here for me was that, although this loader was easier and more efficient to construct, everything about its operation went against what a driver had previously learned and therefore negated any real improvement in efficiency or cost.

In the same way, I think our insistence on traditional nomenclature and vocabulary when teaching students may be easy and efficient for us, but comes at a cost and confusion for students. An example is when we talk about water movement. Many students are very familiar with the concept that molecules move from more concentrated to less concentrated solutions. However, many of my students get confused about water movement in response to osmotic pressure, because water moves from less osmolarity to more osmolarity. Simply talking about the dilution of the solution instead of the osmolarity would solve this problem because then water moves from more dilute to less dilute.

In summary, I encourage all of us to use confusion in our everyday life as a chance to reflect on our teaching; when are we making an analogous mistake to inadvertently mislead our students?

Mark Milanick (milanickm@missouri.edu) is a professor in the Department of Medical Pharmacology and Physiology at the University of Missouri in Columbia.