2/12 



DYNAMIC SYSTEMS 



Sometimes a line of behaviour can be specified in terms of 

 elementary mathematical functions. Such a simplicity is con- 

 venient when it occurs, but is rarer in practice than an acquaintance 

 with elementary mathematics would suggest. With biological 

 material it is rare. 



r*~\ 



imimA0~%iwMJi ■ ; 



Time — *- 



Figure 2/12/1 : Events during an experiment on a conditioned reflex in 

 a sheep. Attached to the left foreleg is an electrode by which a shock 

 can be administered. Line A records the position of the left forefoot. 

 Line B records the sheep's respiratory movements. Line C records 

 by a rise (E) the application of the conditional stimulus : the sound 

 of a buzzer. Line D records by a vertical stroke (F) the application of 

 the electric shock. (After Liddell et al.) 



Another form is the tabular, of which an example is Table 2/12/1. 

 Each column defines one state; the whole table defines one line 

 of behaviour (other tables may contain more than one line of 

 behaviour). The state at hours is the initial state. 



Table 2/12/1 : Blood changes after a dose of ammonium chloride, w 

 = serum pH ; x = serum total base ; y = serum chloride ; z = serum 

 bicarbonate ; (the last three in m. eq. per 1.). 



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