CardioViz Cardiovascular System Visualizer Ryan Roth Damien Suttle Nicholas Yang

Goal Web-based project (Director) For use at Brown and other institutions Targeted at undergraduates and pre-med students Purpose is to serve as a tool to encourage experimentation with cardiovascular physiology Extensible and expandable in the future

Layout and Design (1/2) As little text as possible Show only what the user wants on the screen 3 main panels: animation, graph, and controls Additional boxes for text information and links Incorporation of sounds and narration

Layout and Design (2/2) Animation Graph Controls CardioViz

Animation (1/2) Simplification of the circulatory system Incorporate “real” elements Linked to other concepts related to circulation (i.e. oxygenation of blood, pumping motions, opening/closing/timing of heart valves) What’s wrong with this model?

Animation (2/2) As an example, from our model, it is obvious that the left side (i.e. the veins) occupy a larger region. It is our hope that this will encourage students to associate the veins with larger volumes of blood. Indeed, it is the case that the veins serve as a reservoir for most of the body’s blood. Rather than simply state this fact, as it might be easily done in one of Professor Stein’s lectures, from working with the model, students will gain an intuitive notion of the concept.

Graph (1/2) Basic graphing mechanism is complete Based on mathematical functions; quantitative versus qualitative Current grapher available online at /grapher.htm /grapher.htm

Graph (2/2) Real-time updates of the graph Turn on/off individual graph components (i.e. some factors, when changed, will have little or no effect on both curves of the graph) Note on colors: distinguishable from animation

Controls Variables –Heart rate –Stroke volume Contractility Total peripheral resistance Blood volume Capacitance of the veins

Possible Questions for Study How do changes in heart rate and stroke volume affect the cardiac output? We want to be able to see the changes on the graph and animation in real-time. What factors change cardiac output? How much of an effect do they have?

Educational Theory Target audience limits constructivism (age group, familiarity with computers, prior educational experience) Our subject and goal has been clearly defined by Professor Stein For use in conjunction with an instructional environment, a traditional class (i.e. Biology 80); not a stand-alone tutorial

Tutorials Using the program (i.e. how would a typical user interact with the program?) How to change variables to achieve desired or expected results Constructing the graph curves Math tutorial

Possible Scenarios Change the type of heart (i.e. default normal heart, athlete’s heart, chronically failing heart) Exercise Gunshot wound Drug overdose

Links Tutorials/help Glossary cvphysiology.com The Harvey Project Relevant lectures Web-based feedback by

Team Roles Ryan is handling the math and tutorials Damien and Nick will handle the programming, graphics, and animation

Conclusion It is our hope that providing students with a tool will encourage active experimentation, central to the constructivist philosophy. By this we mean, our hope is to not simply tell students how a particular change in heart factors affect the cardiac output, but instead force them to change the value themselves and see what happens.