THE USE OF A GENERAL-PURPOSE TIME-SHARED COMPUTER 
IN PHYSIOLOGY RESEARCH 
E. Dong, G. C. M. Wiederhold* 
Digital computers have been used in many situations. 
This paper describes the use of a general-purpose, time- 
shared digital computer at Stanford University for 
physiological research. The functions utilized were: (1) 
experimental control, (2) on-line plotting, (3) long-term 
data storage, (4) data reduction, (5) interactive 
language, (6) mathematical modeling, and (7) simu- 
lation. The use of this system has permitted further 
refinements in the study of vagal-heart rate control in 
the dog. 
INTRODUCTION 
In the past ten years there has been a great 
proliferation of computer services for the re- 
searcher in the laboratory. In our University 
environment M^here there are multiple comput- 
ing tasks going on simultaneously, it has been 
advantageous to have a large general-purpose, 
time-shared computer v^^ith programming in a 
high level interactive language, in that the re- 
searcher is able to complete experiments in a 
short time between conception and acquisition of 
the data. 
Experiments can be divided into several 
phases: (1) experimental control, (2) data col- 
lection and reduction, (3) long-term storage, 
and (4) building of mathematical models. Many 
of these computers can provide valuable assist- 
ance. We hope to demonstrate that the avail- 
ability of this type of computer system has 
accelerated the development of certain new con- 
cepts in the control of heart rate. 
At Stanford various types of computer assist- 
ance are provided by the facility termed ACME 
(Advanced Computer for Medical Research 
ACME is a project sponsored by the Special 
Resources Division of the National Institutes 
of Health. It provides time-sharing computer 
services to the researcher in his laboratory us- 
ing an interactive programming language 
termed PL-ACME, which is a sub-set based 
upon IBM-PL-1 for reasons of compatibility.^ 
The machine (Figure 1) has a very large dy- 
namically-shared memory capability to allow 
easy implementation of algorithms, a perma- 
nent centrally maintained file system for re- 
liable and economic long-term storage,* and the 
capability to use alphabetic text as well as 
numeric data. An important feature to physio- 
logical researchers is the direct analog data 
input and output through a peripheral 1800 
computer. There is also direct support for plot- 
ting on-line in the laboratory as well as for 
C.etr.zra't 
lorr.'i nr. 
Ccr.vrnciona) 
• 0 " ! 

i 1 
i 
typewriter slrn/il laboratory 
Input/ computer 
output 
User tcrmtnol station 
Tho ACME computor system ( Jon. 1072 }. 
* Cardiovascular Surgery Division, Stanford University Medical 
Center, Stanford, California. 
Figure 1.— General design of the ACME system. 
1091 
