Selected omissions and capstone presentations: a new approach to student-centered integrative physiology education.

Here, we describe a pedagogical approach that combines didactics with active learning to facilitate integration across physiological systems in a team-taught, graduate-level physiology course. We covered the major physiological systems, with each system preceded by an overview of its evolution/ontogeny to provide a broader perspective. Lectures provided a framework for integration by giving examples of how each system interacted with systems that preceded and followed. In lieu of a final exam, the course culminated in capstone presentations by small groups to promote student-centered learning of integrative physiology. At the beginning of the semester, students were assigned to groups; each group chose from predetermined topics. This allowed them to accumulate information throughout the semester and required them to attend to lecture content to assess how the material applied to their topic, thereby facilitating learning and retention. Faculty were deliberate in choosing material that was presented in each system, and material that was strategically omitted, establishing "gaps" that students filled in their capstone presentations. The final week was dedicated to student preparation for their presentations, which promoted peer-to-peer teaching and problem solving by the group, assisted by faculty as necessary. Capstone presentations demonstrated students' mastery of basic physiological principles and their ability to integrate among physiological systems, and they rated capstone presentations highly in helping with integration and critical thinking. Thus students showed a better understanding of systems physiology and the importance of integration across systems in normal function and in responding to homeostatic challenges.

Wavelength and intensity dependence of retinal evoked responses using in vivo optic nerve recording.

We use a whole-animal model and wavelength-selective optical stimulation to investigate relationships between optical stimulus characteristics and neural signaling. Light-emitting diodes are used to selectively stimulate rod and cone pathways in Rana pipiens. A suction electrode is used to make in vivo measurements of the compound action potential from the optic nerve as the wavelength and intensity of the stimulus is varied. Our results demonstrate that the cone and rod pathways can be separately stimulated and analyzed with our method and, thus, provide a means to model the response of such pathways to more complex stimuli.