INHIBITORY INTERACTION IN THE RETINA 283 



where the strengths of the excitatory and inhibitory influences, their transients 

 and their relative time delays were favorable to the development of an "on- 

 off" response. This shows that an interplay of excitatory and inhibitory 

 influences can indeed generate complex response patterns, that may resemble 

 those produced in the vertebrate retina where neural interactions are more 

 elaborate. 



The eye of Limulus has provided a useful object for the study of neural 

 interaction in a form that is complex enough to have general interest, and yet 

 simple enough to permit quantitative analysis and the development of a formal 

 theory for its concise representation. This analysis has been successful for 

 the steady-state condition, and offers promise of useful extension to the 

 transients. Its significance to visual physiology has been indicated, and its 

 extension to other sensory systems should be useful. It is hoped that it may 

 have general value in the analysis of the complex interactions that characterize 

 the action of all nervous centers. 



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