Zur Frage über die secundären Degenerationen des Hirnschenkels

301

The present investigation was designed to determine the origins in the temporal lobe, and terminations in the pons, of the temporopontine pathway. Injections of tritiated amino acids were placed in multimodal regions in the upper bank of the superior temporal sulcus (STS), and in unimodal visual, somatosensory, and auditory areas in different sectors of the lower bank of the STS, the superior temporal gyrus (STG), and the supratemporal plane (STP). The distribution of terminal label in the nuclei of the basis pontis was studied using the autoradiographic technique. Following injections of isotope into the multimodal areas (TPO and PGa) in the upper bank of the STS, intense aggregations of label were observed in the extreme dorsolateral, dorsolateral, and lateral nuclei of the pons, and modest amounts of label were seen in the peripeduncular nucleus. The caudalmost area TPO projected in addition to the ventral and intrapeduncular pontine nuclei. The second auditory area, AII, and the adjacent auditory association areas of the STG and STP contributed modest projections to the dorsolateral, lateral, and peripedunuclar nuclei, but generally spared the extreme dorsolateral nucleus. The lower bank of the STS, which subserves central vision, the somatosensory associated region at the fundus of the rostral STS, and the primary auditory area did not project to the pons. The higher order, multimodal STS contribution to the corticopontocerebellar circuit may provide a partial anatomical substrate for the hypothesis that the cerebellum contributes to the modulation of nonmotor functions.

Section: Discussionmentioning

confidence: 99%

mentioning

confidence: 99%

Projections to the basis pontis from the superior temporal sulcus and superior temporal region in the rhesus monkey

Schmahmann

Pandya

1991

301

“…for more details see Iioche, 1898). Bechterew (1885Bechterew ( , 1887 and Hoche (1898), on the basis of degeneration studies in human pathological specimens, concluded that these fibers, in contrast to other lemniscal fibers, were descending and Hoche (1898) named the temporal cortex as one of their possible sources of origin. This is also suggested by the presence of fibers entering the lemniscal stratum of the tegmentum from the sublenticular segment of the internal capsule shown as bundle YI by Fore1 (1877, fig. 5. j, Also in a human case with a lesion in the sylvian area, von Monakow (1895) demonstrated descending degenerating fascicles in the mesencephaiic reticular foymation.…”

Section: Temporotegrnental Tractmentioning

confidence: 99%

The connections of the amygdala and of the anterior temporal cortex in the human brain

Klingler¹,

Gloor²

1960

358

163

In recent years the functions of the temporal lobe have been of prime interest to experimental and clinical workers in the field of neurology. Much of this interest has been stimulated by the intriguing problems raised by the clinical symptomatology of temporal lobe epilepsy and by the many observations made in the course of surgical treatment of this form of epilepsy by anterior and mesial temporal lobe excisions inchding the amygdala. Electroencephalographic observations, the responses induced by electrical stimulation of temporal lobe structures during operation and the results of careful pre-and postoperative psychological testing of the patients undergoing these neurosurgical operations have considerably advanced our knowledge of the functional significance of the temporal lobe in man. Thus the physiology of this area has become increasingly a human physiology and, as such, it obviously should rest upon a firm first-hand knowledge of the human anatomy of this region. However, a great deal of our knowledge of the hv.man anatomy of this area rests upon inferences drawn by analogy from studies carried out in subhuman mammalian species.Therefore, it seemed to us timely to restudy the anatomy of this region i n the human brain itself, especially since with the rapid development of stereotaxic neurosurgery a precise knowledge of the specifically human anatomy of this and other a r e x of the brain will assume more and more practical importance.In this presentation of our investigations we shall restrict ourselves to the connections of the amygdala and of the neighboring temporal cortex. The posterior border of the area to be considered here is not shxply defined, but runs roughly along the vein of Labbk. It does not include Heschl's gyrus and its connections nor does it include Ammon's formation. We excluded from our study the callosal connections of the temporal lobe, corticostriatal connections and the primary olfactory connections of the amygdala and of the periamygdaloid cortex. MATE:RIALS AND METHODSThe method applied to this study was that of fiber dissection in the previously frozen brain as developed by one of us (Klingler, '35). In addition a wax model of the basal ganglia and of the neighboring cortex constructed by on of us (Klingler. '41) on the basis of Weigert-stained serial sections through the human brain proved to bc very helpful. Limited use has been made of myelin stained coronal sections of the human brain. Only normal material was used. Technique o f fixing, freezing and dissecting the brainFor fiber dissection studies of the human brain it is important that all parts, including the deepest structures are well fixed. Fixation in the customary 10% iormalin is inadequate, for it fixes rapidly and well the external parts close to the surface, but penetration of the formalin into the deeper parts is slow and insufficient and thus results i n their inadequate fixation. In brains so fixed fiber dissection studies cannot be carried out in a satisfactory way. It is, therefore, necessary to fix the bra...

“…• The external stria (outer stripe of Baillarger, layer 4) was found as a second dip in the intensity profile. A third dip in the intensity profile corresponded to a Kaes-Bechterew stripe (Bechterew, 1891;Kaes, 1907) in layer 3a.…”

Section: Anatomical Interpretation Of Mri Intensity Profilesmentioning

confidence: 96%

“…Of relevance, while Berlin (1858) focused on cyto‐architecture based on neuronal staining, Meynert (1867) described different types of cortices (archipallium and neopallium) based on the lamination produced by the distribution of cell and white matter (WM; for more details, see Fulton, 1937). These remarkable advances were then complemented by myelo‐architectonic and cyto‐architectonic studies by many (Bechterew, 1891; Flechsig, 1920; Ramon y Cajal, 1909). Formal descriptions of the parcellation of the cerebral cortex followed (Smith, 1907; von Economo & Koskinas, 1925; C. Vogt & Vogt, 1919).…”

Section: Introductionmentioning

confidence: 99%

Analyzing the cortical fine structure as revealed by ex‐vivo anatomical MRI

Kruggel

Solodkin

2023

The human cortex has a rich fiber structure as revealed by myelin‐staining of histological slices. Myelin also contributes to the image contrast in Magnetic Resonance Imaging (MRI). Recent advances in Magnetic Resonance (MR) scanner and imaging technology allowed the acquisition of an ex‐vivo data set at an isotropic resolution of 100 µm. This study focused on a computational analysis of this data set with the aim of bridging between histological knowledge and MRI‐based results. This work highlights: (1) the design and implementation of a processing chain that extracts intracortical features from a high‐resolution MR image; (2) a demonstration of the correspondence between MRI‐based cortical intensity profiles and the myelo‐architectonic layering of the cortex; (3) the characterization and classification of four basic myelo‐architectonic profile types; (4) the distinction of cortical regions based on myelo‐architectonic features; and (5) the segmentation of cortical modules in the entorhinal cortex.