Use of Lung Function Diagrams to Memorably House Analogies in Physiology Education
Authors: Bhetwal Bhupal , Wilson Thad 
Published: May 2023

Students find pulmonary physiology difficult and complex. Information overload is a strong deterrent of learning and decreases motivation. Function diagrams are simplified renditions of a complex system that can house a series of analogies and mnemonics for the purpose of concept elaboration and knowledge retrieval. This lung function diagram uses the five lobes (3 of the right and 2 of the left) to link several analogies that when put together describes the major lung functions. The five lobes correspond to (i) Lung compliance & surface tension, (ii) Mechanics of breathing & airway resistance, (iii) Control of breathing, (iv) Gas diffusion and oxygen transport, and (v) Ventilation-perfusion matching. Each lobe serves as a memory palace location for one of the five items but the lobe housing an item has no anatomical relation. The first image is of someone doing a belly flop while holding a big, medium, and small balloon. The small balloon represents thick-walled hard-to-inflate balloon (analogy of fibrosed lung), the medium balloon medium-walled normally-inflated (analogy of normal lung), and the big balloon represents a thin-walled easily-inflated balloon (higher compliance). The belly flop represents water’s high surface tension. The second image is of a mechanic turning on a water spicket. Here the mechanic represents the mechanics involved in respiration. The flow of a liquid out the spicket represents narrow vs. wider aperture extrapolates to air flow and determinants of airway resistance, especially if different size hoses are attached. The third image is of a computer circuit board connected to a small motor. This represents the regulation of respiration, accepting inputs and back-and-forth circuitry with outputs to increase or decrease the speed of the motor or ventilation. The forth image is of a car filled with three commuters returning home (blood flow returning to the lungs) and soda cans and baking soda in the trunk. In this image the four-seat car represents hemoglobin with its four oxygen binding sites, each passenger is an oxygen. The soda represents dissolved carbon dioxide, baking soda represents bicarbonate, and the trunk is the hemoglobin site that binds to carbon dioxide. Passengers getting into of the car and soda cans and baking soda being unloaded from the trunk represents O2 and CO2 binding/unbinding. The final image of gas tanks traveling down a conveyer belt to be filled. Here the gas filling rate of partially filled cylinders represents ventilation, the speed of belt carrying these cylinders represents perfusion. Our overall premise is that simple witty memorable diagrams, function diagrams, that do not look like a detailed figures and graphs may facilitate elaboration and decrease perceived perplexity of learning difficult topics such as pulmonary physiology. This is the full abstract presented at the American Physiology Summit 2023 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.