14/3 REPETITIVE STIMULI AND HABITUATION 



tion (cycle or state of equilibrium). The whole field is thus 

 divisible into regions (each a confluent) such that each region 

 contains one and only one state of equilibrium or cycle, to which 

 every line of behaviour in it eventually comes. The chief pro- 

 perty of a confluent is that the representative point, if released 

 from any point within it, (a) cannot leave the confluent, (b) will 

 go to the state of equilibrium or cycle, where it will remain so 

 long as the parametric conditions persist. 



The division of the whole field into confluents is not peculiar to 

 machines of special type, but is common to all systems that are 

 state-determined and that have more than one state of equilibrium 

 or cycle. 



Habituation 



14/3. Consider now what will happen if a polystable system be 

 subjected to an impulsive (S. 6/5) stimulus S repetitively, the 

 stimulus being unvarying, and with intervals between its applica- 

 tions sufficiently long for the system to come to equilibrium 

 before- the next application is made. 



By S. 6/5, the stimulus S, being impulsive, will displace the 

 representative point from any given state to some definite state. 

 Thus the effect of S (acting on the representative point at a state 

 of equilibrium by the previous paragraph) is to transfer it to some 



Figure 14/3/1 : Field of system with twelve confluents, each containing a 

 state of equilibrium (shown as a dot), or a cycle (X at the left). The 

 arrows show the displacements caused by S when it is applied to the 

 representative point at any state of equilibrium or on X. 



185 



