The nuclear configuration and cortical connections of the human thalamus

The present paper is par t of a series of studies on the human thalamus. The plan is to use suitable pathological material as a substitute for the experimental data available for subhuman studies, and to check such findings against normal preparations. It is hoped to provide thus a better understanding of the more detailed connections of the normal human thalamus and to see in what ways these connections and their functionally associated groups are comparable to, and in what ways they differ from, those of closely related forms. The object, then, is a better understanding of the normally functioning human thalamus. As a useful basis fo r this work, a preliminary r6sum6 of the major nuclear groups of the human thalamus is given. Then the first of the series of cases pertinent to the problem under consideration will be presented. The structure and the connections of the mammalian dorsal thalamus have been studied extensively. There have been relatively few studies of the human thalamus since the beginning of the century; then the work of von AIonakow (1895) formed the basis for an understanding, of this region. The usual descriptions and illustrations of the human thalamus in atlases and modern textbooks are still, for the most part, based on his conceptions. The older workers did not have the advantages of modern technical methods, and their descriptions were very gross, depending on myelin stains or on large nuclear districts stained with carmine. RIost modern textbooks in their mention of recent advances in the form and function of the thalamus use illustrations and references from current work on primates. There are some exceptions to this ; for example, Mettler ( '42) and Riley ( '43) have figured certain of the nuclear groups in the human thalamus.