Information Processing in the Time Domain 



345 



Figure 10 presents the square waves generated by both the positive 

 and negative portions of tlie EKG and its derivatives. The physio- 

 logical information contained in these square waves and in their 

 relations to one another is still largely unknown. Reports of re- 

 cent studies employing general purpose computers and utilizing 

 coding points similar to period analysis indicate success in charac- 

 terizing and classifying normal and pathological subjects (8). We 

 would like to expand one particular problem of EKG analysis 

 as we have approached it in our laboratories. Both low wave 



Fig. 11. Recognition of a 'fat-thin-faV' Square Wave Set. The synthetic function of 



mixed sine waves slowly changes wave shape over time. If, and only if, the wave 



shape generates a square wave sequence within acceptable limits, the complex 



is "recognized," as indicated by the spike in the recognition pulse trace. 



