414 



BRAIN MECHANISMS AND LEARNING 



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1 sec 



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Fig. I 

 EEG patterns following midpontinc and rostropontinc transscctiims 

 Drawings of horizontal sections of the cat's brain stem. Cross hatched areas indicate level and 

 extent of brain stem lesion in the midpoiitine (A) and rostropontinc (B) pretrigeminal prepara- 

 tions. EEG patterns typical for each preparation, as recorded from right (F.d) and left (F.s) 

 frontal areas, arc reproduced below each set of anatomical drawings. It can be noticed that 

 both types of transsection result in the complete interruption of ascending trigeminal in- 

 fluences. Anatomical abbreviations in the original. Anh. ital. Biol., 97, 1-12, 1959. 



