1932] Poliak: Afferent Fiber Systems, Primate Cerehral Cortex 235 



Fig. 30, Experiment I. The degenerated thalamocortical and auditory 

 radiations (sr and ar respectively) as in the preceding figures except that the 

 ventral bundles of the somatic sensory radiation from the ventro-lateral nucleus 

 of the thalamus (their origin visible in fig. 33) are shown here passing through 

 the internal capsule, these fibers being also closest to the auditory radiation. 

 Lesion (L) in the dorso-lat-eral nucleus of tlie thalamus (Th). Note the appear- 

 ance and position of the auditory radiation in the most ventral portion of the 

 internal capsule immediately above the external geniculate body: a dense 

 bundle of short oblique fiber segments. The acoustic fibers pass through the 

 putamen (the latter here much reduced in size) into the white matter of the 

 superior temporal convolution (T,) where they occupy the upper half of the white 

 matter exclusively and ent^r the cortex of the lower wall of the Sylvian fossa 

 (FS). No acoustic fibers whatever reach the cortex around the bottom of the 

 superior temporal sulcus (St,) or any other portion of the temporal cortex. Central 

 sulcus (C), preeentral (CA) and postcentral convolution (CF), inferior parietal 

 convolution (PI), elevation of the cortex in the posterior portion of the Sylvian 

 fossa comparable to the transverse temporal convolution of Heschl (Ttr), middle 

 temporal convolution (T.,). 



