SOME THALAMIC AND CORTICAL MECHANISMS OF TASTE 



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area II or to the auditory system (Benjamin and Welker, 1957 ; Hind et 

 a/., 1958). 



Where then? I would like to suggest the claustrum as a possibility. 

 There is really no substantial evidence for this speculation, but none 

 against it either. The claustrum lies in a very vuhierable position (out- 

 lined area) and in fact, was partially damaged by this lesion (cross section 2). 



In the rat the claustrum is in an even more vulnerable position (Fig. 17) 

 because it has not split off from the rest of the cortex and lies directly under 



Fig. 17. Coronal section of a rat brain through a unilateral lesion removing 

 the composite taste nerve area. The dark-celled mass subjacent to the lesion is 



the claustrum. 



the ventral part of the composite taste nerve area. Cortical lesions which 

 produce taste deficits always damage this dark-celled claustral mass and 

 properly so since it is part of the cortex. 



The speculation that there are gustatory projections to the claustrum may 

 not be substantiated. However, the conclusion that the thalamic taste 

 projections are not confined to the cortical area defined by evoked potentials 

 seems inescapable. 



In summary, although it appeared at one time that the cortex was the 

 known and the thalamus the unknown, the situation is now reversed. 



