Abstract
Two approaches are presented to the study of regulation in the circulatory system. One consists of programming on an analog computer equations to represent part of the system and then, using suitable transducer, substituting the computer for the biological component. An example is presented in which a part of the mechanism which regulates arterial pressure (the carotid sinus) is simulated. The other approach involves simultaneous solution of equations derived to represent each system component. Simulation of a transient disturbance in blood distribution (Valsalva maneuver) is presented to illustrate the use of this approach in predicting the role of each component in determining over-all system behavior.