What would you draw if somebody told you to draw a neuron?
According to a new study, your sketch will depend on how much science education you have, but not in the way you'd expect. In the image above, the top row -- those detailed, labeled, neat renderings -- are the work of undergraduates. The bottom row, with their janky, sparse lines, come from the leaders of neuroscience research laboratories. That martini-glass looking thing over there on the left? That's a neuron, as drawn by a professional scientist. The middle row, some intermediary step, shows drawings from postdocs and graduate students.
These drawings come from a new study published in the journal Science Education. Its authors, a team at King's College London led by education professor David Hay, found that nearly every single undergraduate student they studied (all but three of 126) faithfully reproduced textbook-style neurons, something akin to a canonical image from an 1899 book detailing the brain, which, the authors say, "has enjoyed an unusually pervasive influence." These drawings are "typified by a multipolar cell body and truncated, feathery dendritic processes around a clearly demarcated nucleus." Many of the drawings were annotated.
For the "trainee scientists" -- those in PhD programs or completing a postdoc -- the neurons appeared more like what would be seen in a microscope image. Nuclei were excluded, the number of dendrites was reduced, and orientation was inconsistent -- all characterizing neurons as you would see them "in nature" not in the pages of a textbook.
The final group, those drawn by lab leaders, are characterized by their variety. "Whether by virtue of their simplicity or naturalism," the authors write, "there is a strong impression that these images exhibit the privilege that each researcher appears to reserver for his or her hypothesis about the hidden neuron cell identity."
The authors believed that the undergraduates were missing a "central imaginative step" -- the "ability to embody a neuron's perspective" -- and that it was holding them back from deeper learning. Could they be taught to understand neurons like the more advanced scientists without going through the years of enculturation and research?
They decided to modify the experiment. Before telling the undergraduates to "please draw a neuron," they put had them participate in exercises designed to get the students to think from the perspective of the neuron -- for example, by having students fan out across the lab in a pattern that mimicked a neuron's growth. The authors found that following the interventions, the students drew much more varied images of neurons. "The brief encounters with a teaching approach aimed at embodied knowledge have apparently liberated a divergence of conceptual ideas about brain cells," the authors write. They can't know for sure why, but, "a tempting hypothesis is that postintervention the students have been licensed to show an innately playful and creative approach."
The experiment is a perfect demonstration that knowledge and understanding lead to creativity. The undergraduate drawings weren't wrong; they just were unimaginative, rigid. As people progressed in their scientific careers, their ideas suffused their drawings. If that's not a great reason to commit yourself to trying to understand something new, I don't know what is.