Using lectures to identify student misconceptions: a study on the paradoxical effects of hyperkalemia on vascular smooth muscle

Abstract

Medical students have difficulty understanding the mechanisms underlying hyperkalemia-mediated local control of blood flow. Such control mechanisms are crucial in the brain, kidney, and skeletal muscle vasculature. We aimed to identify medical students’ misconceptions via assessment of students’ in-class knowledge and, subsequently, improve future teaching of this concept. In-class polling was performed with the TurningPoint clicker response system ( n = 860) to gauge students’ understanding of three physiological concepts related to hyperkalemia: membrane potential ( Vm), conductance, and smooth muscle response. Vm includes the concepts of equilibrium potential ( Veq) for specific ions, as well as driving force (DF = Vm − Veq). Students understood the concept of DF (~70% answered correctly), suggesting their understanding of Vm. However, students misunderstood that hyperkalemia results in depolarization (~52% answered correctly) and leads to an increase in potassium conductance (~31% answered correctly). Clarification of the type of smooth muscle as vascular increased the percentage of correct responses (~51 to 73%). The data indicate that students lacked knowledge of specific potassium conductance in various muscle types, resulting in divergent responses, such as the canonical depolarization in skeletal muscle versus hyperpolarization in smooth muscle cells during hyperkalemia. Misunderstanding of this crucial concept of conductance is directly related to the students’ performance. Furthermore, we connected the paradoxical effect of hyperkalemia to pathological acute and chronic hyperkalemia clinical scenarios.

Intuitive concepts in internal medicine and their occurrence in undergraduate medical students in different semesters

“…In a study on causes of worsening acne vulgaris, it was also shown that intuitive concepts common in the general population were still highly prevalent among medical students in their final year of study [ 30 ]. The consistent percentage per semester of intuitive concept selection for internal medicine topics in our study confirmed studies in medical physiology that existing intuitive concepts appeared to have little to no ability to be overcome by previous teaching methods [ 24 ], [ 31 ]. Another study of biomedical science students, using a multilayered approach to study intuitive concepts in cardiovascular physiology, could demonstrate that in nearly one-third of the cases the selection of the intuitive concept was paired with high confidence of having answered the question correctly [ 32 ].…”

The Effect of Using “Student Response Systems (SRS)” on Faculty Performance and Student Interaction in the Classroom

“…Similar findings were reported in previous studies. Following these findings, Bordes et al utilized the SRS to assess students' in-class knowledge by using in-class polling to gauge students' understanding of the key lecture concepts [31]. He concluded that the SRS served as a potential teaching tool to identify student misconceptions and improve student learning outcomes [31].…”

“…Following these findings, Bordes et al utilized the SRS to assess students' in-class knowledge by using in-class polling to gauge students' understanding of the key lecture concepts [31]. He concluded that the SRS served as a potential teaching tool to identify student misconceptions and improve student learning outcomes [31]. Li reported that the use of SRS also benefits the lecturer as the teaching evaluation of the lecturer was significantly better for the SRS group [3,4].…”