278 Injormation Storage and Neural Control 



DISCUSSION OF CHAPTER XI 



Frank Morrell (Palo Alto, California): I would like to ask 

 two questions, Dr. John, both relating to your central theme. 

 In the experiment dealing with equivalence of central stimulation 

 and a peripheral signal you found that highly trained animals 

 punished for errors did not transfer. Do you think that the "equiv- 

 alence'' you demonstrate represents generalization rather than 

 transfer and actually serves to prove the nonequivalence of central 

 stimulation and the peripheral signal? 



On a more theoretical plane, do you think that a representational 

 system which stores information in the form of an ongoing pulse 

 code is an efficient method for storage, or even for comparison? 

 And since it is clear that animals can distinguish frequencies in 

 the visual, somatic or auditory modalities which are far above 

 the range of EEG rhythms, is it necessary to postulate an entirely 

 different coding mechanism for temporal sequences beyond the 

 limited range within which a translation in terms of brain wave 

 response is possible? 



E. Roy John (Rochester, New York): I believe your first 

 question is directed at whether information might be encoded as 

 a wavefoim and stored by a mechanism which could reproduce 

 waveform. Clearly, at some level there must be a common domain 

 of discourse between information about immediate experience and 

 representation of past experience. Recognition of an input requires 

 such an interaction. As I stated in the beginning, there are various 

 possible ways that this might be accomplished. Some workers 

 have suggested neural filter networks, structured by experience, 

 such that passage of an input constitutes identification. It is not 

 clear how such throughput is to be related to the experience 

 which stipulated the filter characteristics. If a filter stands for 

 experience A and permits passage of an impulse when experience A 

 occurs, no mechanism has been proposed which would assign to 

 that passed impulse the content of experience A. 



Other workers have suggested an intracellular macromolecular 

 device functioning almost as a tape recorder to register experience. 

 To my knowledge, no mechanism has been proposed which 

 would achieve "playback"' from these molecular recordings. One 

 can conceive of networks which would accomplish coincidence 



