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JOSEPH DUERSON STOUT 



age duration in vibration rate for the cortical and subcortical, 

 and the percentage relations, i.e., the subcortical average di- 

 vided by the longer cortical. 



The results of this part of the work are not conclusive and are 

 given at this time because of their suggestive value, rather than 

 their power of explanation. In comparison with the results 

 here recorded it is of interest to note that in cat 24 the average 

 cortical latent period, in ten tests, was 30.9 vibrations. 



TABLE 7 

 Comparison of latency of movement for cortical and subcortical points 



The table shows that the latency of the subcortical stimula- 

 tions was approximately 75 per cent of the latency of the stimu- 

 lations of the cortex. In addition to these relations the follow- 

 ing observations were made of the cortical and the subcortical 

 reactions. The amount of current needed for the stimulation of 

 the cortical and of the subcortical tissue was approximately the 

 same. The character of the reactions and the fatiguability of the 

 two tissues was not noticeably different. 



It will be observed that the latent periods for the cortical 

 stimulation vary considerably in the different animals, the dif- 

 ference between the shortest and the longest periods being nearly 

 200 per cent. Similar variations in the latent periods for sub- 

 cortical stimulations were also found, but a comparison of the 

 results in cats 26, 27, and 32 shows that in every case the aver- 

 age subcortical latency is less than that of the cortical. The 

 table gives the results in percentages and shows that the dif- 

 ference is not the same for all animals, in cat 26 the subcortical 

 latency being about 40 per cent less than the cortical latency, 

 while in cat 32 the difference is only about 12 per cent. 



Whether or not the greater delay in cortical stimulation is due 



