Neural Control of Heart Rate: A Conciliation of Models

Two published models for the interaction of sympathetic and parasympathetic effects on heart rate are examined. The models appear to support contradictory conclusions: one was interpreted to imply no interaction, while the other one was said to indicate significant interaction between the two types of autonomic controls. It is shown that the two models are essentially equivalent, and that the different conclusions are due to different interpretations of the concept of interaction.