268 Information Storage and Neural Control 



stimulation, particularly in the reticular formation, to achieve 

 similar results. 



These experiments showed that low frequency stimulation seemed 

 to have an intrinsically inhibitory effect. Perhaps the fact that 

 differential inhibition occurred in the same direction in both of 

 these animals may be understood on this basis. However, this 

 study did not provide evidence in support of the hypothesis that 

 the configuration of labeled potentials during performance of 

 a difTerentiated conditioned response to a TCS represents coded 

 information about the peripheral stimulus being processed by the 

 nervous system. Work must be pursued with more animals, using 

 other frequencies and additional anatomical placements, in order 

 to clarify these questions. 



Yet one can conceive of a number of possible reasons for the 

 results obtained: 1) The brain does not code or process information 

 in a manner which is related to the observed configurations of 

 labeled potentials; 2) powerful intrinsic "resonance'' to low fre- 

 quency input resulted in an uncoded inhibitory effect masking our 

 ability to find differential effects based on the significance of a 

 particular frequency for an animal; or 3) the organization of the 

 coding and processing of this sort of information in differential 

 response might proceed exactly as we would conjecture on the 

 basis of configurations of labeled potentials. Our inability to 

 demonstrate differential effects based on central stimulation at 

 presumably informational frequencies might simply be due to 

 the fact that the response of neural tissue to our artificial waveforms 

 was inappropriate for functional interaction with "brain language." 



DIFFERENTIAL CONDITIONING TO STIMULATION 

 OF A CENTRAL SITE 



A number of experimental strategies have been devised to explore 

 these alternative explanations. One relatively straightforward 

 approach was to attempt to make our artificial input functionally 

 equivalent with brain language. We were struck by the fact that in 

 hundreds of trials we had failed to get any indication of behavioral 

 response to direct central stimulation alone. This seemed to contra- 

 dict the work of Livanov et al. (13), Liberson et al. (12), and Neff ^/ 



