Anastomotic Nets Combating Noise 



A B 



287 



Figure 3 



To explain respiration, we now use a net of three neurons 

 (Fig. 3), and suppose that we want [X], 



[1] [(X) X (X)] 



X 



or. 



[2] 



[(X) X (X)] = [X] 



and compute it as in Equation 1, and tlien decrease every 6 by 

 one so as to compute tlie same [X]. Now every component is com- 

 puting a new function of its input; hence, this net is logically 

 stable under common shift of 6 over a change of one step. If we 

 were to carry it a second step, we would have a net that always 

 fires or never fires. 



The maximum range for neurons with two afferents is clearly 

 two steps, but it can only be achieved by nets with interaction of 

 afferents, and then it can be achieved always and for any number 

 of afferents per neuron. For example. Figure 4 shows these expres- 



