Human clay models versus cat dissection: how the similarity between the classroom and the exam affects student performance

This study examined the effect of different anatomic representations on student learning in a human anatomy class studying the muscular system. Specifically, we examined the efficacy of using dissected cats (with and without handouts) compared with clay sculpting of human structures. Ten undergraduate laboratory sections were assigned to three treatment groups: cat dissection only, cat dissection with handouts, and human clay sculpting with handouts. Exams included higher-order questions that presented novel anatomic images and scenarios that the students did not practice in class. The higher-order anatomy exam questions varied the degree to which students in the different treatments had to transform the anatomic representation studied during laboratory activities to match the representation used in the exam questions. In this respect, exam questions manipulated the similarity between the surface features of the anatomic representations used in the classroom versus the exam. When identifying anatomic structures presented in a photograph or diagram, student performance improved significantly when transformation demands decreased, i.e., students in the human clay sculpting treatment group performed best on human anatomy questions and students in the cat dissection treatment group performed better on cat anatomy questions (independent of the use of handouts). There were similar, but nonsignificant, trends when students were asked functional anatomy questions presented in human and cat contexts. On survey questions designed to measure student attitudes about dissection versus nonanimal alternatives, students typically preferred the method used in their treatment group, suggesting that student preference is too fluid to factor into curricular decisions. When designing curricula, instructors must choose anatomic representations that support their course goals. Human representations are most effective when teaching the human muscular system.