While my anatomy and physiology classroom is full of interesting and helpful models, sometimes I need a little something extra to help students grasp a concept. Last week I shared some items from my “toy box.” Today I’m opening the candy jar.
Students are usually unfamiliar with the concepts of “cortex” and “medulla.” The adrenal gland, the kidney, the ovary, and several other structures exhibit this lay-out. Simply put, the cortex is the outer portion of a structure, and it varies significantly in its function and makeup from the inner medulla. My illustration? The Tootsie Pop. The hard candy shell is the cortex of the pop, and the soft center is the medulla.
Growing up in the 60’s, I loved this commercial (although, strangely, I’ve never been a fan of the candy itself.)
Once I’ve explained the Tootsie Pop analogy, I only need to ask my students, “Which part of the adrenal gland is the cortex?” They reply in unison, “The candy shell!”
Learning the differences between epithelial tissue and connective tissue is a challenge. Epithelial tissue consists almost entirely of cells. Connective tissue has cells, too, but not nearly as many, and it owes most of its functionality to the material between the scattered cells (called “matrix,” since you’re dying to know).
To illustrate this difference, I employ a bag of salted peanuts, which are like individual cells in epithelial tissue. Then I produce a box or can of peanut brittle to represent the connective tissue. Students are quick to point out that the latter “is all about the brittle.” Since the matrix of connective tissue has 2 main components (fibers and ground substance), and brittle is primarily butter and sugar, the metaphor is especially apt.
How do I know that this nutty approach works? Because later in the course when I ask about the composition of connective tissue, someone always blurts out “peanut brittle!”
The latest addition to my jar of candy illustrations was contributed by a pair of students. The structure of flat bones, like the ones that make up the top of the skull, is a sort of sandwich. The outer layers are dense, or compact, bone, and the middle layer is made up of spongy bone, called diploë. Our textbook, Pearson’s Human Anatomy and Physiology, 9e, by Marieb and Koehn, illustrates it like this:
When I presented this in class, one student noted that it looked like Hershey’s Air Delight. I wasn’t familiar with that treat, but the next day another student brought a sample for us to dissect. Everyone agreed that the cross section of the Air Delight looked exactly like a flat bone. So far, every student has remembered what “diploë” means.
Why do these food-related analogies work so well?
- First, learning is always easier when we can associate new concepts with something that is familiar.
- Activating neurons in different areas of the brain seems to consolidate memories. By using candy metaphors, we are involving the olfactory (smell) and gustatory (taste) areas of the brain in the process of consolidating new information in long-term memory.
- Finally, we arrive on the planet with a hard-wired preference for sweet-tasting foods. The memory of treats that we enjoyed as children is a pleasure in itself, so the new information takes on the sheen of pleasure.
I suspect that the combination of these factors makes candy-coated visuals especially effective.
Do you use unconventional visuals in your classes? We would love to hear about them.