Silver studies of degenerating thalamocortical connections.

During recent years, several investigators have used various silver-impregnation methods for the study of degenerating fibers and terminal endings in the central nervous system. Among them are: Miskolczy ('31, '34); Hoff ('32 a and b); Foerster et al ('33); Snider ('36); Gibson ('37 a and b); Rosiello ('37); Schimert ('38, '39); Szentagothai-Schimert ('41); Szentagothai ('42, '43, '48); Glees ('41, '42, '44, '46); Glees et al ('41, '46); Clark and Meyer ('47); Carrea, Reissig, and Mettler ('47, '48); Meyer ('49); Meyer and Allison ('49); Brodal ('49); Wall ('50); Nauta, and Gygax ('51). Estable has been using different variations of silver-impregnation methods for tracing degenerating fibers in the central nervous system since 1935 (see Sosa and Andrew '47), paying special attention to the fact that frequently, in order to obtain best results, it is necessary to use specific variations for each problem. With this in mind, a variation of the Cajal silver-impregnation technic, which would be most accurate for the study of degenerating thalamo-cortical connections, has been sought.