Case Study: Using Metaphors to Scaffold Knowledge

Abstract 

One of the biggest challenges facing Biosciences students is the many complex, sometimes contradictory, often nuanced concepts underpinning biological processes in health and disease. Reflecting on my own teaching experiences, I noted a theme emerging: the use of metaphors and analogies to help students understand the intricacies of cancer. Metaphorical thinking is a useful scaffolding tool, bridging the gap between existing knowledge and new insights. By using relatable examples and drawing comparisons between real-life, everyday ideas, students are engaged and guided from familiar concepts to a deeper, structured understanding of the biology of cancer, as evidenced in positive feedback from both students and colleagues across the University. 

2. Background

Petrie and Oshlag (1993) describe metaphors as a way of “leaping the epistemological chasm, between old knowledge and radically new knowledge.” Shuell (1990) famously said, “If a picture is worth 1000 words, a metaphor is worth 1000 pictures!”. A metaphor provides a conceptual framework upon which to build new understanding based on existing knowledge or previous experience. My use of metaphors in teaching complex concepts underpinning cancer biology has helped me accommodate my students’ existing knowledge and individual learning needs before inviting them to “cross the bridge” with me to build new knowledge.   

3. Methodology

I designed the curriculum and content for the part C cancer biology module, an optional 20 credit semester 2 class that services the Biological Sciences (SSEHS), Biochemistry (SSEHS) and Natural Sciences (SoS) programmes. The lecture series covers a range of topics including the hallmarks of cancer, which contains detailed, molecular processes within cancer cells. For each lecture, I looked for opportunities to create metaphors or analogies to facilitate understanding of a complex idea, for example: 1) a cancer cell’s ability to stimulate autocrine production of its own growth factors is likened to being able to make its own food; 2) their ability to upregulate growth factor receptors on the cell surface is likened to growing additional mouths so they can consume more food; or 3) their ability to stimulate other cells to produce growth factors for them is likened to ordering in a takeaway. Each concept has an everyday metaphor aligned to it so that students can easily recall them and understand how this facilitates cancer growth. 

4. Issues

The main issue I faced was identifying new and original metaphors for similar processes, or for more abstract concepts. Where this did not come naturally, or felt forced, I took a different approach, such as using film clips to illustrate a point, or props and visual aids like using sweets to represent components of the cell. For example, to describe the process of angiogenesis, where tumours grow new blood vessels, instead of a metaphor I used a clip from the 2005 Tom Cruise film, War of the Worlds, to illustrate the process whereby aliens grow blood vessels which spread across the earth (with a sensitivity warning given in advance should anyone wish to look away!). 

5. Benefits

The most striking benefit of using metaphors and analogies in teaching cancer biology is the apparent increase in student understanding. They create an accessible and fun learning tool for students to structure their knowledge, bridging the gap between their existing understanding of a topic and new, complex knowledge. Another key benefit is increased student engagement with the content: one particularly challenging concept in cancer biology is the notion of phenotypic plasticity – that is, a cancer cell’s ability to become a different cell type altogether. For this concept, I invite the students to use themselves as the analogy – they have the potential to become anything they want in life: they may have begun down this particular path in the Life Sciences, but they can change their minds and enter into a different career path ,and then I draw on my own experience and career choices (including a brief interlude as a Tax Advisor!) to provide a relatable example. 

6. Evidence of Success 

I have received both formal and informal positive feedback from students about my approach to teaching and learning (“…things were explained with various anecdotes which were useful and made the concept make more sense.”; “I like the analogies Mhairi would give and it encouraged me to think of my own.”’ “Your passion for the subject really showed in your humour and little fun facts and meant I also enjoyed learning and revising!”). This is further emphasised by positive feedback received in formal peer observations from staff in SSH (“Mhairi illustrated scientific processes with examples that students could relate to, for example using a game of rugby as a metaphor for DNA replication.”; “The use of jellybeans and strawberry laces made students smile and would facilitate information recall.”). My use of metaphors in an educational blog to support learning at a previous institution also received positive feedback from students who cited these as effective learning aids (“…the blog is amazing. Very helpful!”; “Love your blogs. Learnt a lot from these.”; Morris, 2018). 

7. How Can Other Academics Reproduce This? 

The beauty of metaphors and analogies is that anyone in any subject field could use this approach. Our brains are hard wired to look for similarities and patterns and we base new knowledge on existing knowledge and past experiences. This is how babies learn to navigate a new world and it continues throughout life. Think about a key concept you teach and jot down as many examples of real-life metaphors, analogies and anecdotes that could be related back to this concept. The next time you are watching a film or TV programme, look for synergies you could refer to in your teaching (although, be mindful of giving a spoiler alert up front!). Keep a list on a Notes app on your phone so you can quickly and easily jot down ideas as they occur to you. Spend time reflecting on your own learning style – are there metaphors you already use to understand concepts in your field? 

8. Reflections

As I reflect on why my use of metaphors and analogies have been successful in aiding student learning, I believe it hinges on two factors: 1) I use everyday, relatable examples that students will understand (but occasionally I’m reminded of how old I am when some of my pop-culture references are actually older than my students!); and 2) it aligns with my personality and who I am – I’m not trying to be someone else, I’m not trying to shoehorn myself into a teaching style that I don’t fit. Each year I deliver these lectures, I find myself thinking of new metaphors, and so to improve my practice, I make an effort to keep note of these new examples and incorporate the ones that work (e.g., comparing acute inflammation and chronic low-grade inflammation to toasting marshmallows on a flame vs a burning ember) or making a mental note to avoid those that sunk like a lead balloon (e.g., the time I tried to explain how chemotherapy doesn’t reach the centre of a tumour by likening it to taking a bowl of marbles and sprinkling it with icing sugar – whilst it illustrated the point, it was too random to be useful!). Going forwards, I would like to explore the wider application of metaphors in learning by investigating the effectiveness of student-directed development of their own metaphors and whether this improves their memory for concepts even further. 

9. References

Petrie, H., and Oshlag, R. (1993). DOI: 10.1017/CBO9781139173865.030 

Shuell, T.J., (1990). DOI: 10.1080/00405849009543439 

War of the Worlds. (2005). [DVD]. Directed by Steven Spielberg. United States: Paramount Pictures. [relevant clip: https://www.youtube.com/watch?v=O_c3QheDbPI] 

Morris, M., (2018). DOI: 10.1386/jwcp.11.1.67_1