摘要:

An experiment was performed in order to determine the efferent projections of the ventral hippocampus and to compare its projection system with that of the dorsal hippocampus in the cat.Lesions were placed stereotaxically in either dorsal or ventral hippocampus in 25 cats. Animals were sacrificed after post-operative survival periods of 4 to 8 days. The Fink-Heimer and Nauta-Gygax techniques were used to trace degenerating axons and their terminals from ventral and dorsal hippocampus.The results demonstrated: (1) a differential distribution of fibers from the ventral and dorsal hippocampus to the septum; i.e., ventral hippocampal fibers terminate in massive numbers throughout the entire extent of the lateral septum and nucleus accumbens; dorsal hippocampal fibers terminate in lesser amounts in the medial septal nucleus; fibers from the posterior crus of the ventral hippocampus project to the midlateral septum; (2) both dorsal and ventral hippocampal fibers project similarly to the diagonal band of Broca, anterior ventral nucleus of thalamus, lateral hypothalamus, and mammillary bodies. The rostral half of the lateral hypothalamus receives fibers principally of ventral hippocampal origin whereas the posterior half of the lateral hypothalamus and mammillary bodies receive fibers of dorsal hippocampal origin; (3) the paraventricular nucleus of the hypothalamus, posterior hypothalamic nucleus, and nucleus of Darkshewitsch receive a few fibers solely from the dorsal hippocampus; (4) a second efferent pathway from the ventral hippocampus was traced from the alveus to pyriform cortex.

ISSN:0006-8977    

DOI:10.1159/000125433

出版商:S. Karger AG    

年代:1971

数据来源: Karger

摘要:

The efferent connections of the septum in the cat were studied using the Fink-Heimer procedure for staining degenerating axons and their terminals.The results indicate a differential distribution of fibers from the lateral and medial septal nuclei to the ventral and dorsal hippocampus, respectively. Projections from the lateral septal nucleus to the subiculum and pyriform cortex adjacent to the ventral hippocampus were noted. Degenerating fibers could also be followed from the medial septal nucleus to the subiculum, posterior pyriform and entorhinal cortices. Other fibers, probably originating in the medial septal nucleus, join the cingulum bundle and reach the retrosplenial area and presubiculum.These findings taken together with the previous results indicate two distinct reciprocal pathways, the first connecting the lateral septal nucleus and ventral hippocampus, and the second relating the medial septal nucleus und dorsal hippocampus.A marked similarity in the projection pathways from the lateral and medial septal nuclei to other forebrain regions was noted.

ISSN:0006-8977    

DOI:10.1159/000125434

出版商:S. Karger AG    

年代:1971

数据来源: Karger

摘要:

Both anterograde and retrograde degeneration techniques were employed to investigate the cortical projections of the dorsal lateral geniculate, medial interlaminar and posterior nuclei of the thalamus. The dorsal lateral geniculate was found to project principally to cortical areas 17 and 18, with an additional, minor projection to the lateral bank of the middle suprasylvian gyrus; the projection from the medial interlaminar nucleus is considered to be restricted to area 18, while the posterior nucleus appears to have two major cortical projections, to respectively area 19 and the lateral bank of the suprasylvian gyrus.The projection from each thalamic visual nucleus to the respective subdivisions of visual cortex was found to be organised topographically such that anterior and posterior parts of the thalamic nucleus project to anterior and posterior parts respectively of the appropriate cortical areas. The cortical projection of the dorsal lateral geniculate is topographically organised in the medio-lateral dimension also, such that medial parts of the nucleus project to lateral area 17 and medial area 18, while lateral parts of the nucleus project to medial area 17 and lateral area 18; no information was obtained on the medio-lateral organisation of the projections from the medial interlaminar or posterior nuclei.No evidence was found of a projection from the dorsal lateral geniculate, medial interlaminar or posterior nuclei to the contralateral occipito-parietal cortex.

ISSN:0006-8977    

DOI:10.1159/000125435

出版商:S. Karger AG    

年代:1971

数据来源: Karger

摘要:

Both anterograde and retrograde degeneration techniques were employed to investigate the cortical projections of the dorsal lateral geniculate, medial interlaminar and posterior nuclei of the thalamus. The dorsal lateral geniculate was found to project principally to cortical areas 17 and 18, with an additional, minor projection to the lateral bank of the middle suprasylvian gyrus; the projection from the medial interlaminar nucleus is considered to be restricted to area 18, while the posterior nucleus appears to have two major cortical projections, to respectively area 19 and the lateral bank of the suprasylvian gyrus.The projection from each thalamic visual nucleus to the respective subdivisions of visual cortex was found to be organised topographically such that anterior and posterior parts of the thalamic nucleus project to anterior and posterior parts respectively of the appropriate cortical areas. The cortical projection of the dorsal lateral geniculate is topographically organised in the medio-lateral dimension also, such that medial parts of the nucleus project to lateral area 17 and medial area 18, while lateral parts of the nucleus project to medial area 17 and lateral area 18; no information was obtained on the medio-lateral organisation of the projections from the medial interlaminar or posterior nuclei.No evidence was found of a projection from the dorsal lateral geniculate, medial interlaminar or posterior nuclei to the contralateral occipito-parietal cortex.

ISSN:0006-8977    

DOI:10.1159/000125436

出版商:S. Karger AG    

年代:1971

数据来源: Karger

摘要:

Both anterograde and retrograde degeneration techniques were employed to investigate the cortical projections of the dorsal lateral geniculate, medial interlaminar and posterior nuclei of the thalamus. The dorsal lateral geniculate was found to project principally to cortical areas 17 and 18, with an additional, minor projection to the lateral bank of the middle suprasylvian gyrus; the projection from the medial interlaminar nucleus is considered to be restricted to area 18, while the posterior nucleus appears to have two major cortical projections, to respectively area 19 and the lateral bank of the suprasylvian gyrus.The projection from each thalamic visual nucleus to the respective subdivisions of visual cortex was found to be organised topographically such that anterior and posterior parts of the thalamic nucleus project to anterior and posterior parts respectively of the appropriate cortical areas. The cortical projection of the dorsal lateral geniculate is topographically organised in the medio-lateral dimension also, such that medial parts of the nucleus project to lateral area 17 and medial area 18, while lateral parts of the nucleus project to medial area 17 and lateral area 18; no information was obtained on the medio-lateral organisation of the projections from the medial interlaminar or posterior nuclei.No evidence was found of a projection from the dorsal lateral geniculate, medial interlaminar or posterior nuclei to the contralateral occipito-parietal cortex.

ISSN:0006-8977    

DOI:10.1159/000125437

出版商:S. Karger AG    

年代:1971

数据来源: Karger