E. DONG, G. C. M. WIEDERHOLD 
1099 
ponential function with a time constant from 
2.6 to 4.8 sees. 
Lastly, experiments in computer simulation 
suggested a change in the current model of 
pacemaker function which, when modified, sim- 
ulated not only the currently acquired biological 
data but also simulated such known phenomena 
as post-pacemaker depression. 
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6 
o 
o 
£ 4 
bJ 
Q. 
K 
2 - 
.r a 0.6 
6 7 
TIME (SEC) 
10 
Figure 13. — Heart period response to vagal stimulation. 
o — M S oSSo o^^SoSt 
Figure 12. — Simulation for acetylene pulse. 
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