Analysing analogies

For many students, a big challenge in learning chemistry and related disciplines is the conceptualisation of processes at the molecular level. Understanding is typically built by connecting and revising prior conceptions and experiences. To assist with this, instructors often use analogies that relate target concepts to analogies with which students may already be familiar. In this article, Orgill et al discuss biochemistry instructors’ perceptions of the use of analogies in their teaching.

Analogies have been the subject of numerous studies and have been shown to be beneficial in several ways. They can help with developing understanding of new material, visualising abstract information and motivating students to learn meaningfully. They are particularly useful in chemistry where terminology is unfamiliar and concepts are abstract. It has also been demonstrated that there are disadvantages to using analogies, which are detailed in the article.

Five semester-long biochemistry courses taught by different instructors were observed by a researcher, who documented 110 analogies along with notes about their presentation and accompanying explanation, and whether they were clearly identified as analogies and whether their limitations were explicitly discussed. The researchers also interviewed 13 instructors to probe perceptions regarding use of analogies.

The article will be of great interest to any teacher who uses analogies in their teaching and is full of fascinating insights regarding use of analogies, of which just a small subset can be discussed here. A key message was that while the instructors tended to be aware of how analogies should be presented, this was not always reflected in their practice. Only 16 analogies included a visual representation of the analogue, despite that most instructors said they used analogies to help students visualise concepts. Furthermore, although instructors claimed to recognise the importance of stating limitations, this was only actually done in five cases, three of which related to the lock-and-key enzyme analogy. It was also noted that around three-quarters of analogies were explained to some extent with very few explained in detail.

These points indicate that student learning could be supported more effectively than is currently the case, and the authors suggest this might be addressed by the creation of a professional development workshop to increase instructors’ awareness of ways to promote beneficial analogical thinking in their classrooms.