Moreover, chemical block of glutamate transmissions in the contralateral inferior colliculus markedly reduced the ipsilaterally driven FFRs, which, however, were significantly enhanced by blocking the contralateral dorsal nucleus of the lateral lemniscus. Thus, FFRs in inferior colliculus to ipsilateral stimulation were facilitated by excitatory projections from the contralateral inferior colliculus but suppressed by inhibitory projections from the contralateral dorsal nucleus of the lateral lemniscus.. 
The topography and neuronal structure of the dorsal nucleus of the lateral geniculate body (GLd) of the common shrew and the bank vole are similar.
(3) At the transition zones between the vMGC and the superficial dorsal nucleus of the MGC dorsal division, and between the vMGC and the ventrolateral nucleus, there were relatively broad clusters of a high density of large-terminal structures from the two cortical domains, which overlapped extensively.
Accordingly, we recorded bursting behavior in single cells from awake, behaving rhesus monkeys in first-order (the lateral geniculate nucleus, the ventral posterior nucleus, and the ventral portion of the medial geniculate nucleus) and higher-order (pulvinar and the medial dorsal nucleus) thalamic relays.
In contrast to the temporal fields of the auditory cortex, which receive input mainly from the ventral medial geniculate body (or "main sensory nucleus"), the dorsal fields of the auditory cortex receive strong input from the "associated nuclei" of the medial geniculate body, especially from the anterior dorsal nucleus of the medial geniculate body. The anterior dorsal nucleus is as significant for the dorsal fields of the auditory cortex as the ventral nucleus of the medial geniculate body is for the temporal fields of the auditory cortex.
The projections to the MGD consistently arborized in its ventral margin made up of the deep dorsal nucleus of the MGD.
The dorsal nucleus (Pd), which densely expresses AChE, projects to posterior and ventral areas of temporal extrastriate cortex, areas TP and TPI.
Ipsilaterally projecting retinal axons also showed an increase in density and distribution in the dorsal nucleus of the LGB.
Intracerebral infusions of Na2SeO3 in the lateral dorsal nucleus resulted in retrogradely labeled neurons that were located in the postsubiculum, and also in the pre- and parasubiculum.
A dorsal pathway innervates the thalamic lateral dorsal nucleus (VLG), the reuniens and rhomboid nuclei (VLG and IGL), and the paraventricular nucleus (IGL).
In addition, AAF and particularly DP and VP project to paralemniscal regions around the dorsal nucleus of the lateral lemniscus (DNLL), to the DNLL itself and to the rostroventral aspect of the superior olivary complex.
Ipsilaterally projecting retinal axons also showed an increase in density and distribution in the dorsal nucleus of the LGB.
More ventrally located injections, focused onto the posterior intralaminar and peripeduncular nucleus, almost exclusively labelled neurons in layer 1 of the external nucleus and the dorsal part of the dorsal nucleus.
The dorsal nucleus of the lateral lemniscus (DNLL) is a binaural nucleus whose neurons are excited by stimulation of the contralateral ear and inhibited by stimulation of the ipsilateral ear.
Extracellular recordings were made with microelectrodes from single neurons in the rat's dorsal nucleus of the lateral lemniscus (DNLL) and response characteristics were determined for monaural and binaural acoustic stimulation.
Retino-LP projections were sparse, occurred throughout the nucleus, and could be classified into 1) simple en passant varicosities and terminal swellings found on poorly branched fibers in all LP subdivisions, 2) string-like configurations of varicosities detected largely in the medial subdivision of the LP, and 3) terminals resembling retinogeniculate endings occurring mainly in the rostral part of the superficial subdivision of the LP adjacent to the dorsal nucleus of the lateral geniculate body.
The synaptic events underlying the excitation of neurons in the rat's dorsal nucleus of the lateral lemniscus were studied by whole-cell patch-clamp recordings in a brain slice preparation of the auditory midbrain. Synaptic responses were evoked by a bipolar stimulating electrode placed on the lateral lemniscus just ventral to the dorsal nucleus. Under voltage-clamp conditions, dorsal nucleus of the lateral lemniscus neurons responded to stimulation of the lateral lemniscus with excitatory postsynaptic currents. The results indicate that both N-methyl-D-aspartate and non-N-methyl-D-aspartate receptor-mediated synaptic responses are present in dorsal nucleus of the lateral lemniscus neurons of rats at 21-35 days of age. The long-duration N-methyl-D-aspartate component is probably responsible for the prolonged inhibitory effect of dorsal nucleus of the lateral lemniscus neurons on physiological responses in the rat's inferior colliculus..
The dorsal nucleus of the lateral lemniscus also contained GABA-positive projection neurons.
Extirpation of one eye (usually the right) destroys afferents to both lateral geniculate bodies dorsal nucleus (CGLd) and superior colliculi (CS), being severely impaired by the degeneration of retino-geniculate and collicular synapses.
The ipsilaterally projecting double-labeled cells tended to have larger somata than the single- and double-labeled cells projecting to the contralateral superior colliculus and/or dorsal nucleus of the lateral geniculate body..
Large multipolar CB+ neurons with radiate dendrites characterize the dorsal nucleus.
Giant endings were observed in a small area in the dorsal nucleus (D) of the dorsal division of the medial geniculate body (dMGB), near its border with the vMGB. Projections from AII gave rise to a main terminal field of small endings in D; a second terminal field consisting of giant endings intermingled with small endings was found in the deep dorsal nucleus (DD) of dMGB.
Inputs to the dorsal nucleus and medial division were also observed.
Superficial dorsal nucleus neurons are oriented from medial to lateral, imparting a slightly laminated appearance to the neuropil. Suprageniculate nucleus neurons have radiating dendritic fields that project spherically; they have fewer branches than dorsal nucleus neurons.
Cells in the superficial dorsal nucleus have weekly laminated dendrites, while dorsal nucleus neurons have spherical dendritic fields.
In the medulla oblongata, immunoreactive neurons and processes were detected in the principal sensory trigeminal nucleus, the trapezoid body, the raphe magnus, the pontine reticular nuclei, the supragenual nucleus, the prepositus hypoglossal nucleus, the medial and spinal vestibular nuclei, the dorsal cochlear nucleus, the medullary reticular field, the nucleus of the solitary tract, the gracile and cuneate nuclei, the dorsal nucleus of the vagus nerve and the oral, interpolar and caudal parts of the spinal trigeminal nucleus.
Sparse FLI was detected in the superior olivary complex, the pontine nuclei and the ipsilateral dorsal nucleus of the lateral lemniscus, whereas the contralateral dorsal nucleus of the lateral lemniscus was moderately labeled.
The dorsal nucleus of the lateral lemniscus (DLL) is the main source of inhibitory influence in the auditory brainstem of mammals.
Injection of Evans Blue (EB) and 4',6-diamidino-2-phenylindole dihydrochloride (DAPI), fluorescent dyes, into the dorsal nucleus of the lateral geniculate body (dLGN) and the ipsilateral superior colliculus (SC) of albino rats, retrogradely labelled retinal ganglion cells (RGCs).
However, the dorsal nucleus was cabp(-).
These labeled structures included the central nucleus of the amygdala; the entopeduncular nucleus; the globus pallidus; the reticular and ventral lateral geniculate nuclei of the thalamus; parts of the hypothalamus including the dorsal, lateral, and posterior hypothalamic areas and the ventromedial and parvicellular nuclei; the zona incerta and fields of Forel; parts of the substantia nigra including the pars reticularis and pars lateralis, and the retrorubral area; the pretectum; the intermediate and deep layers of the superior colliculus; the periaqueductal gray; the dorsal nucleus of the raphe; portions of the reticular formation, including the mesencephalic, pontis oralis, pontis caudalis, gigantocellularis, ventralis, and lateralis reticular nuclei; the nucleus cuneiformis; the marginal nucleus of the brachium conjunctivum; the locus coeruleus; portions of the trigeminal complex, including the principal sensory and spinal nuclei; portions of the vestibular complex, including the lateral division of the superior nucleus and the medial nucleus; deep cerebellar nuclei, including the medial and lateral cerebellar nuclei; and lamina VII of the cervical spinal cord.
Strongly positive were Purkinje, basket and stellate cells of the cerebellum, cerebral cortical nonpyramidal cells, and neurons in the thalamic reticular and ventrolateral nuclei, subthalamic nucleus, lateral and medial geniculate bodies, vestibular and cochlear nuclei, spinal trigeminal nucleus, cuneate and gracile nuclei, and dorsal nucleus of Clarke.
The front of retinal axons crosses the chiasm, extends over the primitive dorsal nucleus of the lateral geniculate body (LGBd) by E13, and advances to the back of the superior colliculus (SC) by E13.5-E14.
On P3 and P4, 30 h after tracer was deposited in the cortex, The HRP reaction product was observed in the dorsal nucleus of the lateral geniculate body and in the lateral posterior nucleus of the thalamus, but no labeled axons were observed in the ventral nucleus of the lateral geniculate body (LGBv) until P5.
The deep dorsal nucleus contains bitufted neurons that polarize with the long axis of the midgeniculate bundle and intermingle with stellate neurons.
The adult dorsal nucleus has medium-sized, loosely packed neurons. The deep dorsal nucleus is situated among the fibers of the midgeniculate bundle and contains loosely packed round and fusiform cells; the latter cell type constitutes a minor proportion of the adult neuronal population but the major cell type in immature animals. The caudodorsal nucleus, which occupies the caudal tip of the MGB and rostrally courses superior to the dorsal nucleus, contains small, dark staining multipolar cells; the ventrolateral nucleus courses inferior to the MGv.
Injection of the fluorescent tracers, Evans blue (EB) and Primulin (Pr), or EB and 4',6-diamino-2-phenylindol dihydrochloride (DAPI), respectively, into the dorsal nucleus of the lateral geniculate body and the superior colliculus on the ipsilateral side have demonstrated the existence of retinal ganglion cells having uncrossed bifurcating axons in the albino rat.
The results showed that the uncrossed retinogeniculate fibers were distributed almost entirely in the ipsilateral segment of the dorsal nucleus of the lateral geniculate body, and the extent of terminal distribution of the fibers observed in rabbits with one eye enucleated during the young adult stage was essentially the same as that in the normal rabbit. The uncrossed retinogeniculate fibers labeled by the wheat germ agglutinin conjugated to horseradish peroxidase passed through the dorsal nucleus of the lateral geniculate body without any branching until they reached the ipsilateral segment.
In the neurons of the dorsal nucleus of the lateral geniculate body, the cytoplasm of dark-reared mice was less developed and the cytoplasm/nucleus ratio was significantly smaller in the dark-reared mice than in the controls.
We also noted areas of abnormally heavy terminal fields arranged in patches in coronal sections in the dorsal nucleus of the lateral geniculate body (LGd).
Afferent projections to the thalamic lateral dorsal nucleus were examined in the rat by the use of retrograde axonal transport techniques. Small iontophoretic injections of horseradish peroxidase were placed at various locations within the lateral dorsal nucleus, and the location and morphology of cells of origin of afferent projections were identified by retrograde labeling. Peroxidase injections in the dorsal lateral part of the lateral dorsal nucleus result in labeled neurons in all of the ipsilateral pretectal nuclei, but especially those that receive direct retinal afferents. In contrast, peroxidase injections in ventral medial portions of the lateral dorsal nucleus result in fewer labeled pretectal cells, and these labeled cells are found exclusively in the pretectal nuclei that do not receive retinal afferents. Other labeled cells following injections in the rostral and medial portions of the lateral dorsal nucleus are seen contralaterally in the medial pretectal region and nucleus of the posterior commissure, and bilaterally in the rostral tips of laminae IV and V of the superior colliculus. These results are discussed with regard to the type of sensory information that may reach the lateral dorsal nucleus and then be relayed on to the medial limbic cortex..
At the same time, stimulus-evoked increases were decreased in the dorsal nucleus of the lateral lemniscus and inferior colliculus, and virtually eliminated in the medial geniculate and auditory cortex.
Eye movements evoked by local electrical stimulation of the dorsal nucleus of the lateral geniculate body were analyzed in cats with extirpated visual cortex and in intact cats. The possible pathways for transmission of information from the dorsal nucleus of the lateral geniculate body to structures of the oculomotor system are discussed..
No such organization was observed in the caudal part of PM nor in the ventrolateral nucleus, while in the dorsal nucleus, the proportion of tone-responding units was too low for a significant analysis..
When two of the principal targets of retinofugal axons, the superior colliculus and dorsal nucleus of the lateral geniculate body, are ablated in newborn hamsters and the somatosensory (ventrobasal) or auditory (medial geniculate) thalamic nuclei are partially deafferented, the optic axons form permanent, abnormal connections in the latter nuclei.
In old-age rabbits, marked changes occur in the thalamic medial dorsal nucleus and lesser changes occur in electrical activity of the LGB.
The effect of high-frequency electrical stimulation of the raphe dorsal nucleus on the excitability cycles of the visual evoked potentials was studied. During stimulation of the raphe dorsal nucleus a facilitation of the visual excitability cycles in all structures studied occurred as compared to the cycles obtained before the stimulation. The data suggest that the raphe dorsal nucleus is involved in the modulation of the excitability of the visual afferent pathway and that this modulation after high-frequency stimulation of the nucleus is probably related to the increased excitability level in the nonspecific brain structures..
The incidence of degenerative debris is significantly higher in the peripheral margins of the dorsal nucleus, a pattern also seen in the retina and the superior colliculus, suggesting that a differential cell death may be involved in the formation of regional specializations in the visual system..
Labelled perikarya were observed in the dorsal nucleus of the lateral geniculate body, the medial and lateral nuclei of the optic tract, the pretectal nuclei and the superior colliculus.
Thus axons of groups I, III, IV, and VI are found in each nucleus, although group VI axons are conspicuous in the superficial dorsal nucleus, and group IV endings are much more elaborate in the dorsal and deep dorsal nuclei than in the superficial dorsal nucleus. For example, both the dorsal nucleus and the deep dorsal nucleus receive the same groups of afferent axons, but the axonal plexus is more diffusely and evenly distributed in the dorsal nucleus, whereas the neuropil of the deep dorsal nucleus is highlighted by aggregates of grumous endings, more irregularities in the distribution of the axonal plexus, and many more fibers of passage.
The relative size of the eyes, optic nerves, chiasms and tracts, and of the dorsal nucleus of the lateral geniculate body is distinctly larger in Primates than in (theoretically) isoponderous Insectivora.
Cells of origin of the tecto-LP (lateroposterior nucleus of the thalamus) projection and the tecto-LGNd (dorsal nucleus of the lateral geniculate body) projection were studied in the albino rat by means of retrograde transport of wheat germ agglutinin conjugated to horseradish peroxidase (WGA-HRP).
The medial part of the ICC projects to the deep dorsal nucleus, which contains only units tuned to high frequencies. The major inputs to the caudodorsal nucleus (DC) stem from nucleus sagulum and the pericentral nucleus of the inferior colliculus (ICP).
Other less numerous afferents in the midbrain included the dorsal and median raphe nuclei and the dorsal nucleus of the lateral lemniscus.
By 16 DAB, 2-DG uptake also increased during WBN exposure in the dorsal nucleus of the lateral lemniscus, inferior colliculus and medial geniculate nucleus.
Similarly, in the lateral geniculate, only the dorsal nucleus showed an increased response to greater stimulus frequencies.
The ICC loci also projected bilaterally onto the MGB in the form of caudorostrally oriented columns of terminals; these columns had their caudal aspects located in the medial and their rostral aspects located in the deep dorsal nucleus of the dorsal division. Injections in the ICP produced autoradiographic labeling in the caudal dorsal nucleus (Dc) of the dorsal division of the MGB.
Eighty-four percent of principal cells in the dorsal nucleus of the lateral geniculate body exhibited a transient depression of spontaneous activity following optic tract stimulation. These findings support the hypothesis that antidromic activity, generated during the evoked response in striate cortex, has a significant influence on excitability pattern of principal cells in the dorsal nucleus of the lateral geniculate body..
In 17 human brains of different sex and age it was demonstrated, for the first time, that there exist wide volumentric differences in the dorsal nucleus of the lateral geniculate body (minimal--66.6 mm3, maximal--152 mm3).
A significant inverse correlation between plasma glucose concentration and the rate of glucose consumption was found in the lateral nucleus of the solitary tract, dorsal nucleus of the vagus, perifornical area where fibres of the medial forebrain bundle course, the superior olivary nucleus and the interstitial nucleus of the stria terminalis.5.
The dorsal nucleus receives projections from the midbrain tegmentum. The deep dorsal and anterodorsal nuclei have neurons which resemble those in the dorsal nucleus. Both receive projections from the roof nucleus of the inferior colliculus but the deep dorsal nucleus receives an additional projection from the parabrachial tegmentum.
The ventral nucleus is developing earlier than the dorsal nucleus.
The retina and the dorsal nucleus of the external geniculate body were stated to have efferent connections with the same nuclei in the anterior hypothalamus.
Effects of chronic ablation of the visual cortex (VC) were studied in the perigeniculate reticular neurons (PGR neurones) which were located in the thalamic reticular nucleus immediately adjacent to the dorsal nucleus of the lateral geniculate body and identified as the I-cells of Burke and Sefton.
In some experiments the effects were examined by recording field responses of the dorsal nucleus of LG (LGd) and the visual cortex (VC) to electrical stimulation of the optic chiasm (OX).
In urethane-anesthetized rats, neurons responding to electrical stimulation of the optic nerve (ON) with bursts of spikes were searched for in the region of the thalamic reticular nucleus close to the dorsal nucleus of the lateral geniculate body (LGBd).
The number of labeled cells arising after injection of the isotope on ED 16 indicates that neurogenesis ceased somewhat earlier in the dorsal nucleus of the LGB than in the ventral.
The work describes a new for dolphins type of the cytoarchitectonic organization and topographo-anatomical features of the dorsal nucleus of the external geniculate body found in the dolphin Phocaena phocaena. This fact is of significance showing the total amount of nerve cells in the dorsal nucleus of the external geniculate body of the Phocaena phocaena to be equal to 6,6% as compared with the white-sided dolphin.
With the aid of the cytospectrophotometry method the author studied the influence of light deprivation (the exposure of animals to darkness during 8 weeks following birth) on neurons of the dorsal nucleus of the external geniculate body of rats according to the index of glutamatedehydrogenase activity.
The dorsal nucleus of the lateral geniculate projected via the optic radiation to area 17 of the cerebral cortex.
The results show that fibres arise in the deep layers of the cortex of AI, pass through the deep subdivision of the dorsal nucleus of the MGB as well as through the magnocellular MGB. and end in the pars lateralis of the ventral nucleus of the MGB, Arising from AII, axons pass through the magnocellular MGB and end in the superficial and deep subdivisions of the dorsal nucleus extending to the most caudal part of the MGB. Of the peri-auditory areas, only the suprasylvian fringe projects to the parvicellular MGB, and it sends axons to the dorsal nucleus of the MGB.
Some trapezoid body fibers ascend via the contralateral lateral lemniscus to VNLL, DNLL (dorsal nucleus of the lateral lemniscus), and CNIC.
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