We used our senses, and because we can see farther than we can hear, or feel, or taste, or smell (thankfully) our vision was the sense that served us best. Along with the other senses, we predominantly used vision to find food so we could feed, to spot predators so we could fight or flee, and to evaluate members of the opposite sex so we could f… breed.
Vision had time to evolve through many millennia. The brain systems that help with decoding text, while promising, are still developing and long-term storage of verbal information is hard. Perhaps the case for using more imagery in learning is best made with the picture superiority effect (PSE), a well-researched phenomenon that shows we remember and retrieve information presented in pictures better than verbal (written and spoken) knowledge.
But doing it is not be as simple as it sounds. Telling students to imagine a concept will not be enough for some, because their spatial capacity — the ability to make, manipulate, and modify visual images in their mind — might not be well developed as a result of its previous underuse. Anyone can close their eyes and conjure a tree, but take a highly abstract concept such as the atom and most students will revert to the age-old, crude, and full of misconceptions “solar system” model. And then chemistry teachers, myself included, wonder: Why oh why do they miss so many easy atom questions on the test?
All kids start out curious. We see this in babies when they gaze in amazement at new faces and objects. Where does this curiosity go and why do some students dread high school science classes and often mask anxiety with indifference? We could blame traditional schooling, but do we truly know? It’s not that simple nor does it do us any good to dwell while teaching. The best course is to show them how to reawaken their imagination.
Imagination awakened — that’s a powerful learning tool. While not in the job description, it is the teacher’s job is to help students use their imagination in the context in which it’s often underutilized — the classroom. The more abstract the concept we teach is, the more important it becomes to create visual reference points, mental imagery that makes it more concrete. At first, we can provide visuals and model how to generate them to our students.
For example… The atom is the simplest building block of matter and one of the most abstract and difficult concepts to correctly understand for students, because it’s unlike anything they’ve ever seen. It’s very small, yet the electrons are very far away from the nucleus — relatively speaking… The nucleus is where pretty much all of the atom’s mass is in the form of protons and neutrons, but it is the smallest part of the atom — relatively speaking… The electrons weigh close to nothing but make up the largest region of the atom we call the electron cloud as the electrons create a sort of an “after image” when they revolve really fast (some calculations have it close to 5,000,000 miles per hour) around the nucleus in the so-called orbitals, which aren’t even paths electrons follow, but rather probabilities of where they can be. Moreover — due to the fact that the electrons are about two thousand times smaller than the protons or neutrons, and they are spaced out, and they are sparse — the electron cloud and the atom itself is comprised of mostly… empty space.
If you don’t teach chemistry, are not a science nerd, or always thought of an atoms as a bunch of balls revolving around a cluster of balls in the middle like planets around the sun, it’s perfectly normal if you’ve developed a migraine reading the above. Scientists don’t completely understand what the atom looks like themselves, and if they tell you they do, they are lying.
I always draw a (very unartistic) football stadium to represent the atom and to aid the student understanding of what it might look like and its scale. I draw the coin the ref flips in the center of the field and ask students to think of it as the nucleus. Then, I draw a few randomly spaced out tiny dots where the stands are and ask my students to imagine they are grains of sand — each ''sitting” in its own seat far away and each representing one electron. Then, I ask them to create this mental image: Remove the stadium, refs, seats, and everything else your mind conjured previously and leave only the coin and the grains of sand suspended in space. Finally, I tell students to animate it: imagine the grains of sand (electrons) revolving around the coin (nucleus) in a three-dimensional space — not like planets around the sun, but rather, the would-be-paths can be horizontal or vertical or skewed in any direction around the nucleus.
The point is to help my students to start seeing things with their mind not just eyes - to use their imagination to draw mental representations of concepts - and to do it often. Ideally, students will learn to create mental images for everything verbal they learn so it is stored in two different but connected parts of the brain, which will then aid recall and understanding. While such practice of converting verbal into visual is natural for some people, other learners must be shown how to do it and given frequent opportunities to better develop their visual-spatial awareness and abilities through deliberate practice.
Dual Coding
The mental model of the atom I created in my own mind for myself is something I share with my chemistry students to tie the insanely abstract to something more tangible. But there’s more to it…
The Dual Coding Theory (DCT) explains two ways of storing memories in the human brain — verbal (text, speech, hearing) and non-verbal (focusing on images). The benefit of having two separate systems of information encoding is that our mind can hold information related to one concept in two different regions of the brain. During initial processing, neurons in different regions of the brain “fire and wire” together connecting the verbal and the visual representations of the same concept. Through repeated processing, these neural pathways thicken (myelination) leading to more elaborate recall, faster application, and deeper understanding of the concept. It’s like having two different people continually discussing a concept and learning from each other by bringing two different ways of looking at the same thing into their interactions.