Ventral Nucleus Of Lateral Lemniscus


The spatial organization of projections from the ventral cochlear nucleus (VCN) to the ventral nucleus of the lateral lemniscus (VNLL) and from the VNLL to the central nucleus of the inferior colliculus (CNIC) was investigated by using neuroanatomical tracing methods in the gerbil.  

Among auditory nuclei, the majority of ChAT-IR cells are in the superior olive, particularly in and around the lateral superior olive, the ventral nucleus of the trapezoid body and the superior paraolivary nucleus. A few ChAT-IR cells are found in the cochlear nucleus and the ventral nucleus of the lateral lemniscus.  

We found robust auditory activity in Uva and determined that Uva is innervated by the ventral nucleus of lateral lemniscus, an auditory brainstem component.  

Octopus cells, neurons in the most posterior and dorsal part of the mammalian ventral cochlear nucleus, convey the timing of synchronous firing of auditory nerve fibers to targets in the contralateral superior paraolivary nucleus and ventral nucleus of the lateral lemniscus.  

Recordings were made from single neurons in the rat's ventral nucleus of the lateral lemniscus (VNLL) to determine responses to amplitude-modulated (AM) tones.  

The ventral nucleus of the lateral lemniscus (VNLL) has been implicated in the processing of such temporal features of a sound.  

Responses to monaural and binaural tone bursts were recorded from neurons in the rat's ventral nucleus of the lateral lemniscus (VNLL).  

The synaptic pharmacology of the ventral nucleus of the lateral lemniscus (VNLL) was investigated in brain slices obtained from rats of 14-37 days old using intracellular recording techniques.  

The function of the ventral nucleus of the lateral lemniscus (VNLL), a secondary processing site within the auditory brain stem, is unclear.  

The main axon used the IAS and followed one of two routes occasionally giving off olivary complex collaterals on their way to the contralateral ventral nucleus of the lateral lemniscus (VNLL).  

Strong HCN1 staining was present on octopus and bushy cells of the ventral cochlear nucleus, principal neurons of the lateral and medial superior olive, and neurons of the ventral nucleus of the lateral lemniscus.  

Some units resembled the response of constant latency neurons found in the ventral nucleus of the lateral lemniscus of bats.  

In addition, we found high levels of Kv1.1 in neurons of the columnar subdivision of the ventral nucleus of the lateral lemniscus and in ventral periolivary cell groups.  

The medial division of the ventral nucleus of the lateral lemniscus (VNLLm) contains a specialized population of neurons that is sensitive to interaural temporal disparities (ITDs), a potent cue for sound localization along the azimuth.  

The ventral nucleus of the lateral lemniscus (VNLL) is a major source of input to the inferior colliculus.  

These neurons resided in the posteroventral and anteroventral cochlear nucleus, the dorsal cochlear nucleus, the lateral superior olive, the medial nucleus of the trapezoid body, the dorsal and ventral nucleus of the lateral lemniscus, and the central nucleus of the inferior colliculus.  

The responses of single neurons in the posterior part of the ventral nucleus of the lateral lemniscus were recorded to stimulation with binaurally correlated and binaurally uncorrelated noise. Neurons in the posterior part of the ventral nucleus of the lateral lemniscus encode the interaural level difference of binaurally correlated and binaurally uncorrelated noise with equal accuracy and precision.  

Notably, Kv3.1 mRNA was not expressed in neurons of the medial and lateral superior olive and a subpopulation of neurons in the ventral nucleus of the lateral lemniscus.  

Some penetrations yielded predominantly monaural responses with a fairly broad dynamic range, similar to those recorded from the ventral nucleus of the lateral lemniscus (LLV) and the cochlear nucleus angularis, whereas other penetrations contained predominantly binaural responses sensitive to interaural time differences (ITD).  

The ventral nucleus of the lateral lemniscus (VNLL) is a prominent neuronal group that lies within the auditory pathway connecting the auditory lower brainstem and midbrain.  

We have studied by in situ hybridization for GAD65 mRNA in thick sections and by semiquantitative postembedding immunocytochemistry in consecutive semithin sections, the expression of gamma-aminobutyric acid (GABA) and glycine in cell bodies and axosomatic puncta of the rat ventral nucleus of the lateral lemniscus (VNLL), a prominent monaural brainstem auditory structure.  

In both the dorsal and ventral nuclei of the lateral lemniscus, alpha1, beta3 and gamma2L are the main subunit messenger RNAs; the ventral nucleus also expresses the delta subunit.  

Moderate levels of Y1 immunoreactivity were found the in the main olfactory bulb, dorsomedial part of suprachiasmatic nucleus, paraventricular hypothalamic nucleus, ventral nucleus of lateral lemniscus, pontine nuclei, mesencephalic trigeminal nucleus, external cuneate nucleus, area postrema, and nucleus tractus solitarius.  

These include: cochlear nucleus afferents to periolivary (lateral nucleus of the trapezoid body, LNTB) cells that project to the inferior colliculus; cortical afferents to periolivary (ventral nucleus of the trapezoid body, VNTB) cells that project to the cochlear nucleus; and serotoninergic and noradrenergic afferents to periolivary (LNTB and VNTB) cells that project to the cochlear nucleus.  

It was found that injections made into the ventrolateral pons around the ventral nucleus of the lateral lemniscus and superior olive could block periaqueductally elicited vocalization.  

In the diencephalon, labeled cells were present in all the mid-line and intralaminar thalamic nuclei; the lateral posterior, pulvinar and suprageniculate nuclei; the ventral nucleus of the lateral geniculate body and the medial geniculate body.  

alpha7 mRNA and protein are expressed in selected regions of the cochlear nucleus (CN), inferior colliculus (IC), medial superior olive, lateral superior olive, ventral nucleus of the lateral lemniscus and superior paraolivary nucleus.  

The ventral nucleus of the lateral lemniscus (VNLL) is a major auditory nucleus that sends a large projection to the inferior colliculus.  

Labeling in the intermediate nucleus of the lateral lemniscus and the magnocellular part of the ventral nucleus of the lateral lemniscus together comprised nearly 40% of all labeled cells.  

The physiological properties including current-voltage relationships, firing patterns, and synaptic responses of the neurons in the ventral nucleus of the lateral lemniscus (VNLL) were studied in brain slices taken through the young rat's (17-37 days old) auditory brain stem.  

In the lateral superior olive, the medial nucleus of the trapezoid body, and the ventral nucleus of the lateral lemniscus, the distribution of AMPA receptor subunits changed drastically with age.  

Neurons that respond to unmodulated tones with a sustained discharge are found in the dorsal nucleus (DNLL), intermediate nucleus (INLL) and multipolar cell division of the ventral nucleus (VNLLm). Neurons that respond only at the onset of a tone make up a small proportion of cells in DNLL, INLL and VNLLm, but are the only type found in the columnar division of the ventral nucleus (VNLLc).  

Extracellular recordings were obtained from single neurons in the multipolar and columnar divisions of the ventral nucleus (VNLLm and VNLLc), the intermediate nucleus (INLL) and the dorsal nucleus of the lateral lemniscus (DNLL).  

These include the lateral superior olive (LSO), ventral nucleus of the lateral lemniscus, medial superior olive, dorsomedial and ventromedial periolivary nuclei, and the MNTB itself.  

[ iii] Transient elevations of release occurred at 59 days in the ipsilateral posteroventral CN ([ 14C]glycine) and bilaterally in the ventral nucleus of the lateral lemniscus ([ 14C]GABA) after ossicle removal, and bilaterally in the medial superior olive ([ 14C]glycine) after cochlear ablation.  

In contrast to the ease of finding tonotopicity in other nuclei, both anatomical and electrophysiological methods have failed to demonstrate a clear and simple tonotopic map within the ventral nucleus of the lateral lemniscus (VLL).  

Results show an attenuation of Fos expression following TMR in the dorsal and ventral cochlear nuclei, ventral nucleus of the lateral lemniscus and medial geniculate nucleus.  

The results from FG retrograde labeling alone showed that neurons in the dorsal nucleus of the lateral lemniscus (DNLL) bilaterally, in the intermediate and ventral nucleus of the lateral lemniscus (INLL and VNLL) ipsilaterally, and in the ICC contralaterally project to the ICC.  

Input projections were observed ipsilaterally from: the medial and lateral superior olivary nuclei; the superior paraolivary nucleus; the dorsolateral and anterolateral periolivary nuclei; the dorsal and ventral divisions of the ventral nucleus of LL; the dorsal and intermediate nuclei of LL; the central nucleus, external nucleus and dorsal cortex of the IC outside the injection site; and small projections from central gray and the medial geniculate body.  

Both types of units were found throughout the lateral lemniscus except for the columnar division of the ventral nucleus, where all units tested exhibited latency ambiguity.  

Contralaterally, the majority of labeled fibers were located in the ventral nucleus of the trapezoid body and the ventral nucleus of the lateral lemniscus. With the exception of calyceal-type endings in the contralateral ventral nucleus of the lateral lemniscus, the varicose fibers in all regions, including the contralateral medial nucleus of the trapezoid body, were beaded, en passant type terminal varicosities..  

The ventral nucleus contained mostly glycine-immunoreactive neurons (81%), and about half of these were also GABA-immunoreactive. Neurons in the ventral nucleus had fewer immunoreactive perisomatic puncta than neurons in either the dorsal or the intermediate nuclei.  

Additional afferent input originated from the ipsilateral ventral nucleus of the lateral lemniscus.  

Neurons of the columnar region of the ventral nucleus of the lateral lemniscus of Eptesicus fuscus respond with high-precision constant-latency responses to sound onsets and possess remarkably broad tuning.  

The ventral nucleus of the lateral lemniscus (VNLL) is implicated in processing monaural sounds, because its neurons receive input chiefly from the contralateral cochlear nucleus.  

The ventral nucleus of the trapezoid body (VNTB) showed sparse but significant innervation by both somatostatin and substance P-positive structures.  

Cytoarchitectonic criteria were used to distinguish three subdivisions of the ventral nucleus of the lateral lemniscus in guinea pigs. Based on the cell types they contain and their patterns of input, we distinguished ventral, dorsal, and anterior subdivisions of the ventral nucleus of the lateral lemniscus. The differences in constituent cell types and in patterns of inputs suggest that each of the three subdivisions of the ventral nucleus of the lateral lemniscus makes a distinct contribution to the analysis of acoustic signals..  

Levels of GluR4 were higher in the anterior portion of the ventral nucleus of the lateral lemniscus.  

Calbindin D-28k was present in cartwheel cells of the dorsal cochlear nucleus, in almost all neurons of the medial nucleus of the trapezoid body, and in globular cells in the ventral nucleus of the lateral lemniscus. This was also evident in the ventral nucleus of the lateral lemniscus where calbindin D-28k-immunoreactive terminals were found in the medial portion, while the calretinin-immunoreactive terminals were observed in the lateral portion.  

For instance, the ventral nucleus of the lateral lemniscus projected predominately to the anterior DNLL and provided little or no inputs to the posterior DNLL, whereas the medial superior olive innervated the posterior but not the anterior DNLL.  

Quantitatively, the ipsilateral ventral nucleus of the lateral lemniscus is the most important source of GABAergic input to the CNIC.  

Focal injections of the tracer biocytin, made in physiologically defined frequency regions of the CNIC, labelled laminated axonal terminal fields in the ipsilateral dorsal nucleus of the lateral lemniscus, and bilaterally in the ventral nucleus of the trapezoid body and the dorsal cochlear nucleus. Labelling was also present in the rostral periolivary nucleus, but we could not distinguish a clear border between the terminal fields in this nucleus and those in the ventral nucleus of the trapezoid body. Labelling observed in the ventral nucleus of the lateral lemniscus, and to a lesser extent in the dorsal nucleus of the lateral lemniscus, was accompanied by retrogradely labelled somata and therefore we cannot conclude unequivocally that the CNIC projects to these lemniscal nuclei. High-frequency regions in the CNIC project to the medial parts of the ventral nucleus of the trapezoid body and dorsal cochlear nucleus, while low-frequency regions in the CNIC project to the lateral parts of the ventral nucleus of the trapezoid body and dorsal cochlear nucleus.  

An analysis of the central projections of the ventral nucleus of the trapezoid body (VNTB) in the rat, a region of the superior olivary complex known for its neuronal heterogeneity, was made using two anterograde axonal tracers, [ 3H]leucine and biotinylated dextran amine (BDA).  

There were also differences in the pattern of expression of these mRNAs in the various brainstem auditory nuclei; there was no preprotachykinin mRNA in any part of the superior olivary complex, only somatostatin mRNA was found in the ventral cochlear nucleus, and expression of preproenkephalin mRNA was pronounced in the ventral nucleus of the trapezoid body and the rostral periolivary zone.  

It is expressed in: (1) motor nuclei such as the oculomotor nucleus, trochlear nucleus, motor trigeminal nucleus, abducens nucleus, facial nucleus, ambiguus nucleus, dorsal motor nucleus of vagus and hypoglossal nucleus; (2) several sensory-related nuclei like the mesencephalic trigeminal nucleus, ventral nucleus of the lateral lemniscus, lateral and spinal vestibular nuclei, ventral and dorsal cochlear nuclei and nucleus of the trapezoid body; and (3) other regions such as the red nucleus, dorsal raphe nucleus, pontine nuclei, three cerebellar nuclei (medial, interposed and lateral), Purkinje cells, cells in the granular layer of the cerebellum, locus coeruleus, several areas of the reticular nucleus and area postrema..  

The intermediate nucleus (INLL) and the two divisions of the ventral nucleus (VNLL) receive almost exclusively monaural input from the anteroventral and posteroventral cochlear nuclei and from the medial nucleus of the trapezoid body.  

This study attempts to determine if the medial (MSO) and lateral superior olive (LSO), medial nucleus of the trapezoid body (MNTB), ventral nucleus of the lateral lemniscus (VNLL), and central nucleus of the inferior colliculus (ICc) contain glutamatergic synaptic endings.  

In the brainstem, where the bulk of the labelling was concentrated, several nuclei showed a high level of transcript expression, including the superior olivary complex, nucleus of the trapezoid body and the ventral nucleus of the lateral lemniscus.  

The data presented in this study indicate that one site of plasticity underlying this adaptive adjustment is in the posterior division of the ventral nucleus of the lateral lemniscus (VLVp), the first site of ILD comparison in the auditory pathway.  

The intense oxidase reactions were present in the red nucleus, oculomotor nucleus, trochlear nucleus, ventral nucleus of the lateral lemniscus, dorsal and ventral cochlear nuclei, vestibular nuclei, nuclei of posterior funiculus, nucleus of the spinal tract of the trigeminal nerve, lateral reticular nucleus, inferior olivary nucleus, and hypoglossal nucleus.  

All neurons in the columnar division of the ventral nucleus of the lateral lemniscus maintained low variability of latency over a broad range of stimulus conditions.  

In the avian auditory system, the posterior division of the ventral nucleus of the lateral lemniscus (VLVp) is the first site where the levels of sound arriving at the two ears are compared.  

A moderate or low density of immunoreactive cell bodies was observed in the nucleus of the brachium of the inferior colliculus, pericentral nucleus of the inferior colliculus, ventral nucleus of the lateral lemniscus and in the external division of the lateral reticular nucleus. The periaqueductal gray, brachium of the inferior colliculus, nucleus of the brachium of the inferior colliculus, locus coeruleus, nucleus incertus, Kölliker-Fuse nucleus, facial nucleus, medial nucleus of the solitary tract and the area postrema contained a moderate density of immunoreactive fibres, whereas the pericentral nucleus of the inferior colliculus, nucleus sagulum, cuneiform nucleus, dorsal nucleus of the raphe, superior central nucleus, central, lateral and paralemniscal tegmental fields, ventral nucleus of the lateral lemniscus, dorsal tegmental nucleus, postpyramidal nucleus of the raphe, nucleus ambiguus, accessory dorsal tegmental nucleus, dorsal motor nucleus of the vagus and the inferior olive had the lowest density of immunoreactive fibres..  

Fewer descending projections terminated in the ipsilateral ventral nucleus of the lateral lemniscus, superior paraolivary nucleus, and rostral periolivary region; and even fewer ipsilateral projections terminated in the area surrounding the lateral superior olive, caudal periolivary region, and the lateroventral periolivary region. Descending neurons of the inferior colliculus also project to the contralateral hindbrain first via the lateral lemniscus and then the trapezoid body, to terminate in the contralateral medioventral periolivary region, superior paraolivary nucleus, rostral periolivary region, and the ventral nucleus of the lateral lemniscus.  

Anatomically, the axons of SBCs cross the midline in the dorsal component of the trapezoid body and typically innervate the medial superior olive (MSO) on both sides, the ipsilateral lateral superior olive (LSO), and the contralateral ventral nucleus of the lateral lemniscus (VNLL).  

Although other auditory nuclei in the brain-stem, the ventral nucleus of the lateral lemniscus, the trapezoid body and the auditory nerve responded to transient stimuli with an amplitude larger than that of the IC, no amplification occurred with 50 Hz stimuli in these nuclei.  

The central nucleus of the IC projects in a topographic order to the dorsal nucleus of the lateral lemniscus (DLL), the rostral periolivary nucleus (RPO), the ventral nucleus of the trapezoid body (VNTB), and the dorsal cochlear nucleus (DCN).  

In addition, numerous cells in the pedunculopontine and laterodorsal tegmental nuclei, the ventral nucleus of the lateral lemniscus, the medial and lateral divisions of the parabrachial nucleus, and the medial and lateral superior olive were labeled.  

In two neurons the ascending axon formed terminal arbors in the ventral nucleus of the lateral lemniscus, and the dorsal nucleus of the lateral lemniscus could be identified as a target of one neuron.  

Animals with lesions that spared DNLL but destroyed the intermediate and ventral nucleus of the lateral lemniscus had normal binaural response functions.  

Strong immunoreactivity was observed in the ventral and dorsal divisions of the ventral nucleus of lateral lemniscus somata and the ventral division's columnarly organized fiber plexus.  

After stimulating adult rats with pure-tone pulses, bands of Fos-immunoreactive neurons revealed the frequency representation in seven brainstem nuclei: all three subdivisions of the cochlear nucleus, the lateral superior olive, the medial nucleus of the trapezoid body, the ventral nucleus of the trapezoid body, the rostral periolivary nucleus, the dorsal nucleus of the lateral lemniscus and the inferior colliculus.  

A moderate density of cell bodies containing the peptide was observed in the ventral nucleus of the lateral lemniscus, accessory dorsal tegmental nucleus, retrofacial nucleus and in the lateral reticular nucleus, whereas a low density of such perikarya was found in the interpeduncular nucleus, nucleus incertus, nucleus sagulum, gigantocellular tegmental field, nucleus of the trapezoid body, nucleus praepositus hypoglosii, lateral and magnocellular tegmental fields, nucleus of the solitary tract, nucleus ambiguous and in the nucleus intercalatus. Finally, few immunoreactive fibers were visualized in the interpeduncular nucleus, cuneiform nucleus, locus coeruleus, nucleus incertus, superior and inferior central nuclei, nucleus sagulum, ventral nucleus of the lateral lemniscus, nucleus praepositus hypoglosii, medial vestibular nucleus, Kölliker-Fuse area, nucleus ambiguous, retrofacial nucleus, postpyramidal nucleus of the raphe, nucleus of the solitary tract, dorsal motor nucleus of the vagus, lateral reticular nucleus and laminar and alaminar spinal trigeminal nuclei..  

A medium density of ChAT-positive terminals was observed in all or parts of: the substantia nigra zona compacta (ferret), ventral tegmental area (ferret), superficial grey layer of the superior colliculus, intermediate and deep layers of the superior colliculus, lateral central grey, area medial to the parabigeminal nucleus, inferior colliculus, dorsal tegmental nucleus, ventral tegmental nucleus (ferret), pontine nuclei, ventral nucleus of the lateral lemniscus (ferret), midline pontine reticular formation, ventral cochlear nucleus, dorsal cochlear nucleus, lateral superior olive, spinal trigeminal nuclei, prepositus hypoglossal nucleus, lateral reticular nucleus, paragigantocellular nucleus, and the dorsal column nuclei including the cuneate, external cuneate, and gracile nuclei.  

Most cells in the intermediate nucleus and the columnar division of the ventral nucleus of the lateral lemniscus were cabp(+).  

The heaviest projection from the periolivary regions to both divisions of the cochlear nucleus arose bilaterally in the ventral nucleus of the trapezoid body.  

Neuronal selectivity for ITD is generated in the nucleus laminaris (NL) and conveyed to both the anterior portion of the ventral nucleus of the lateral lemniscus (VLVa) and the central (ICc) and external (ICx) nuclei of the inferior colliculus.  

A third collateral headed rostrally toward the ventral nucleus of the lateral lemniscus (VNLL), giving off occasional small sidebranches.  

These cells were located in the pericentral inferior colliculus, dorsal nucleus of the lateral lemniscus, dorsomedial to the ventral nucleus of the lateral lemniscus and immediately lateral to the central grey.  

Allowing 0.6 ms for total synaptic transmission time in every relay nuclei, systematic comparisons of the shortest latencies of evoked potentials and shock-elicited startle, as well as estimations of conduction velocities in pathways from cochlea to C1-C5 spinal cord, suggest that one primary acoustic head startle circuit consists of ventral cochlear nucleus (postsynaptic evoked potential: 1.4 ms; startle: 3.6-4.0 ms), ventral nucleus of the lateral lemniscus (evoked potential: 2.3 ms; startle: 2.7-2.8 ms), medial bulbar reticular formation (evoked potential: 3.2-3.6 ms; startle: 2.1 ms), spinal interneuron and motoneuron. The nucleus reticularis pontis caudalis (NRPC) cannot be considered as an head startle relay intercalated between the ventral nucleus of the lateral lemniscus (VNLL) and the medial bulbar reticular formation (MBRF) because mean latencies of field potentials in the pontine RF and the LL nucleus are the same (2.3 ms).  

Neurons located in the ventral nucleus, in the dorsal nucleus of the lateral lemniscus and in the inferior colliculus developed parvalbumin immunoreactivity mostly between P11-P15 (ventral nucleus), P15-P19 (dorsal nucleus) and P15-P19 (inferior colliculus), respectively.  

In the ventral nucleus of the lateral lemniscus, PV-positive cells were immunoreactive neither to glycine nor to GABA.  

Six h after injection of [ 3H]glycine in the inferior colliculus, autoradiographically labeled cells were found ipsilaterally in the ventral nucleus of the lateral lemniscus, the lateral superior olive and the dorsomedial periolivary nucleus. The results implicate uncrossed projections from the ventral nucleus of the lateral lemniscus, lateral superior olive, and dorsomedial periolivary nucleus as the principal sources of inhibitory glycinergic inputs to the inferior colliculus..  

A thin branch, usually starting from the large branch, wound its way through the medial nucleus of the trapezoid body to its termination in the ventral nucleus of the trapezoid body.  

In addition, moderately labeled cells were abundant in the nucleus of the solitary tract, medial and inferior vestibular nuclei, parabrachial area, dorsal and ventral tegmental nuclei of Gudden, central gray matter, ventral nucleus of the lateral lemniscus, and reticular formation (small neurons).  

To physiologically test the effectiveness of the cryoprobe, two specific behaviors mediated by well defined neural structures were measured; electrically elicited hindleg flexion in ketamine-anesthetized rats, mediated by the pyramidal tract; and the acoustic startle reflex in freely behaving rats, mediated by the ventral nucleus of the lateral lemniscus. Cooling of the ventral nucleus of the lateral lemniscus at 0 degrees C reversibly blocked the acoustic startle reflex.  

While the projection pattern is generally in accordance with other mammals, several species-characteristic features are noted: i) the lateral superior olive (LSO) receives tonotopically organized input from both the AVCN and PVCN; ii) the CN-projections to medial nuclear groups of the SOC located between the LSO and the medial nucleus of the trapezoid body do not support previously suggested homologies; iii) the ventral nucleus of the LLC can be subdivided into two divisions with distinct input patterns from the AVCN and PVCN, respectively..  

These injections labeled a group of large multipolar cells lying between the ventral nucleus of the lateral lemniscus and the superior olivary complex.  

The ventral nucleus of the lateral lemniscus (anterior division) contains both immunoreactive terminals and some GABAergic neurons. Immunoreactive terminals are distributed throughout the neuropil of the ventral nucleus of the lateral lemniscus (posterior division), whereas multipolar and small fusiform GABAergic neurons predominate in the dorsal regions of the nucleus.  

The dorsomedial EE region receives inputs primarily from the ipsilateral intermediate nucleus of the lateral lemniscus (INLL) and ventral nucleus of the lateral lemniscus (VNLL), and the contralateral ICc.  

Acoustic startle is a short-latency reflex mediated by a neural circuit consisting of the ventral cochlear nucleus (VCN), ventral nucleus of the lateral lemniscus (VLL), the nucleus reticularis pontis caudalis (RPC), and the spinal cord.  

Other nuclei, the lateral superior olive, the ventral nucleus of the lateral lemniscus, the dorsomedial periolivary nuclei, and the medial nucleus of the trapezoid body showed an ipsilateral bias in their projections to the cochlear nucleus.  

They occur in the dorsal cochlear nucleus, the periolivary region, the ventral nucleus of the lateral lemniscus, and in the central nucleus of the inferior colliculus..  

Of HRP-labeled nerve cells found in the brainstem, about 60% and 10% were located in the ipsilateral lateral superior olivary nucleus (LSO) and the contralateral ventral nucleus of the trapezoid body (VTB), respectively. Seven percent and 5% of the labeled neurons were definitely observed in the ventrocaudal part of the contra- and ipsilateral ventral nucleus of the lateral lemniscus (VLL), respectively.  

Rats were implanted with bilateral cannulas in an area just medial to the ventral nucleus of the lateral lemniscus, an obligatory relay along the acoustic startle pathway.  

The greatest number of labelled neurons was found in the cochlear nuclei contralateral to the injection site, the ipsilateral medial superior olivary nucleus, both lateral superior olivary nuclei, the ipsilateral ventral nucleus of the lateral lemniscus, both dorsal nuclei of the lateral lemniscus, and the contralateral inferior colliculus.  

the neurones of the central nucleus of the inferior colliculus terminate in the ventral nucleus of the medial geniculate body.  

The medial superior olive, superior paraolivary nucleus, and ventral nucleus of the trapezoid body essentially show ipsilateral projections to the central nucleus.  

The distribution of best frequencies (BFs) of units in all three nuclei of the lateral lemniscus showed an overrepresentation in the range corresponding to the constant-frequency (CF) part of the echolocation signal ('filter frequency' range): in the ventral nucleus of the lateral lemniscus (VNLL) 'filter neurons' represented 43% of all units encountered, in the intermediate nucleus (INLL) 33%, and in dorsal nucleus (DNLL) 29% (Fig. On the average, filter neurons in ventral nucleus had higher Q10dB-values (about 220) than did those in intermediate and dorsal nucleus (both about 160, Fig 2d). Response patterns and tuning properties showed higher complexity in the dorsal and intermediate nucleus than in the ventral nucleus of the lateral lemniscus (Figs.  

In contrast, a number of nuclei and cell groups are very poorly developed or absent in the human auditory system: these include several types of small neurons in the cochlear nuclei, the lateral olivary nucleus, nucleus of the trapezoid body, and ventral nucleus of the lateral lemniscus.  

Pentobarbital, and especially pentobarbital plus ketamine, enhanced stimulus-evoked increases in relative 2-DG uptake in lower auditory nuclei: the cochlear nuclei, superior olivary complex and ventral nucleus of the lateral lemniscus.  

After bilateral injections of both tracers, double-labelled cells were found in small numbers within all the large neurone medial system nuclei and the ventral nucleus of the lateral lemniscus.  

In the mesencephalic region, the Kölliker-Fuse nucleus, parabrachial nucleus, and the ventral nucleus of the lateral lemniscus projected mainly to the ipsilateral lateral subdivision of NVII.  

Pathways from AVCN diverge to 3 major targets in the lateral lemniscus, the intermediate nucleus and 2 divisions of the ventral nucleus (VNLL).  

DYN B cell bodies were present in nonpyramidal cells of neo- and allocortices, medium-sized cells of the caudate-putamen, nucleus accumbens, lateral part of the central nucleus of the amygdala, bed nucleus of the stria terminalis, preoptic area, and in sectors of nearly every hypothalamic nucleus and area, medial pretectal area, and nucleus of the optic tract, periaqueductal gray, raphe nuclei, cuneiform nucleus, sagulum, retrorubral nucleus, peripeduncular nucleus, lateral terminal nucleus, pedunculopontine nucleus, mesencephalic trigeminal nucleus, parabigeminal nucleus, dorsal nucleus of the lateral lemniscus, lateral superior olivary nucleus, superior paraolivary nucleus, medial superior olivary nucleus, ventral nucleus of the trapezoid body, lateral dorsal tegmental nucleus, accessory trigeminal nucleus, solitary nucleus, nucleus ambiguus, paratrigeminal nucleus, area postrema, lateral reticular nucleus, and ventrolateral region of the reticular formation.  

Afferents project bilaterally from the parabigeminal nuclei, the nucleus of the optic tract, the posterior pretectal region, the dorsal part of the lateral posterior-pulvinar complex and the ventral nucleus of the lateral lemniscus; and ipsilaterally from the substantia nigra pars reticulata, the pars lateralis of the ventral lateral geniculate nucleus, the intergeniculate leaflet, the zona incerta, the olivary pretectal nucleus, the nucleus of the posterior commissure, the lateral thalamus, Forel's field H2, and the ventromedial hypothalamus.  

Labeled fibers projecting into the opposite lateral lemniscus (LL) terminated in the ventral nucleus of the lateral lemniscus (VNLL) and the CNIC.  

In the ventral nucleus of the lateral lemniscus, labeled neurons were observed only when the HRP was injected into the ipsilateral IC..  

Terminal labeling, tentatively attributed to principal cell axons, was also seen in the ventral nucleus of the lateral lemniscus (VNLL) and the dorsomedial and ventromedial periolivary nuclei.  

Positive cells were present in the superior and inferior colliculi, the ventral cochlear nuclei, the ventral nucleus of the lateral lemniscus, nucleus cuneatus, nucleus gracilus, and the substantia gelatinosa.  

Labelled cells were also found in the ventral nucleus of the lateral lemniscus, the ventral parabrachial nucleus, the gigantocellular reticular nucleus, the lateral nucleus of the substantia nigra, the prerubral nucleus of the thalamus, the hypothalamic ventromedial nucleus, the zona incerta and in the anterior and lateral hypothalamic areas.  

Acoustic and electrical brain stimulation studies have revealed that the ventral nucleus of the lateral lemniscus is a specific site within the brain stem where a previously conditioned stimulus modulates a simple reflex, the acoustic startle response.  

Consequently, not only parietal lobe lesions and limited lesions in the inferior medial portion of the posterolateral ventral nucleus (VPL) and lateral part of the posteromedial ventral nucleus (VPM), but also damage to a restricted group of fibres reaching these nuclei, may cause cheiro-oral syndrome..  

Large labelled neurones were found both ipsi-laterally and contra-laterally in the dorsomedial periolivary region, including the medial nucleus of trapezoid body and in the ventral and lateral nuclei of the trapezoid body and the ventral nucleus of lateral lemniscus.  

The topographic distribution of projections from the ventral nucleus of the lateral lemniscus (VNLL) in the cat was investigated with the autoradiographic tracing method. The descending projection ended mainly in the dorsomedial periolivary region and ventral nucleus of the trapezoid body.  

Cell size in the lateral superior olive, medial nucleus of the trapezoid body, ventral nucleus of the lateral lemniscus, anteroventral cochlear nucleus, dorsal cochlear nucleus, and facial nucleus was also smaller (by 9-21%) in albinos than in pigmented animals but none of these differences was statistically reliable.  

Massive projections to the inferior colliculus were found from the contralateral and ipsilateral dorsal nucleus of the lateral lemniscus and ipsilateral ventral nucleus of the lateral lemniscus.  

Projections to primarily the contralateral inferior colliculus arise in the dorsal and ventral cochlear nuclei, the auditory nerve nucleus and the spinal trigeminal nucleus pars caudalis, while ipsilateral projections arise in the superior paraolivary nucleus, the ventral nucleus of the trapezoid body, the ventral nucleus of the lateral lemniscus, the paralemniscal nucleus, the deep layer of the superior colliculus and the parabrachial nucleus.  

Stimulation of the mammary nerve, with a stimulus that causes milk ejection and an increase in prolactin release, produced a significant increase in the RMA of the PVN, SON, the pars distalis and pars nervosa and the spinothalamic tract, and a significant decrease in the ventromedial and mediodorsal nuclei of the thalamus, the zona incerta, the red nucleus and the ventral nucleus of the lateral lemniscus.  

The medial superior olive (MSO), superior parolivary nucleus, and ventral nucleus of the lateral lemniscus all maintain ipsilateral projections to the IC.  

Connection of a posteromedial region of the ventral nucleus of the lateral lemniscus were examined in the cat using the autoradiographic tracing method. The autoradiographic findings revealed that many axons from the posteromedial region of the ventral nucleus of the lateral lemniscus that entered the superior colliculus continued into the midbrain reticular formation. Other sub-collicular regions also contained labeled cells in these cases, including the main body of the ventral nucleus of the lateral lemniscus and scattered cell groups around the superior olivary complex..  

The ventral nucleus of the lateral lemniscus has a distinct columnar organization.  

At 14 DAB, 2-DG uptake increased during WBN in the entire cochlear nuclear complex, superior olivary complex, and ventral nucleus of the lateral lemniscus.  

After HRP injections into the lateral hypothalamic area, labeled cells were found mainly in the medial prefrontal and infralimbic cortices, lateral and dorsal septal nuclei, nucleus accumbens, bed nucleus of the stria terminalis, medial and lateral amygdaloid nuclei, lateral habenular nucleus, peripeduncular nucleus, ventral tegmental area, mesencephalic and pontine central gray, ventral nucleus of the lateral lemniscus, lateral parabrachial area, raphe nuclei and the nucleus locus coeruleus.  

The results indicate that the predominant ascending projections to inferior colliculus originate in (1) contralateral cochlear nucleus, (2) contralateral and ipsilateral lateral superior olive, (3) ipsilateral medial superior olive, (4) ipsilateral ventral nucleus of the lateral lemniscus, (5) ipsilateral and contralateral dorsal nucleus of the lateral lemniscus, and (6) contralateral inferior colliculus. A nucleotopic organization suggests that the heaviest terminations of contralateral inferior colliculus are medial and dorsal in inferior colliculus, of medial superior olive are dorsal and lateral, of superior olivary complex are rostral, of cochlear nucleus are caudal, and of ventral nucleus of the lateral lemniscus are caudal..  

In sharp contrast, the ventral nucleus of the lateral lemniscus is the recipient of afferents from many cells in the contralateral ventral cochlear nucleus and from only a few cells in the superior olivary complex.  

Moreover, extraolivary origin of the efferent innervation of the cochlea could be demonstrated bilaterally in the ventral nucleus of the lateral lemniscus..  

Additional thalamic components were traced to specific sites within the "posterior group," including a medial component largely traversed by lemniscal axons and a caudolateral component lying between the principal nucleus of the medial geniculate and ventral nucleus of the lateral geniculate.  

Virtually all neurons of the ventral nucleus of the lateral lemniscus and the medial superior olivary nucleus ipsilateral to the injection side appear to project to the IC.  

Many of the neurons which contribute to the contralateral bundle are located adjacent to the ventral nucleus of the lateral lemniscus.  

Auditory structures: inferior colliculus (external and pericentral nuclei), dorsomedial periolivary nucleus, nuclei of the trapezoid body, ventral nucleus of the lateral lemniscus.  

Virtually all cells of the ipsilateral ventral nucleus of the lateral lemniscus and medial superior olive appear to project to the colliculus. Topographic projections matched previously described tonotopic organization of the colliculus and all major subcollicular nuclei except the ventral nucleus of the lateral lemniscus.  

Auditory fibers crossing the midline in the TB projected contralaterally to: (1) the medial trapezoid nucleus (MTN), (2) the ventral dendritic zone of the MSO, (3) the ventral nucleus of the lateral lemniscus (VNLL), and (4) the central nucleus of the inferior colliculus (CNIC).  

After deep collicular injections numerous labeled cells were consistently found in the parabigeminal nucleus, the mesencephalic reticular formation, substantia nigra pars reticulata, the nucleus of posterior commissure, the pretectal area, zona incerta, and the ventral nucleus of the lateral geniculate body.  

Abundant degeneration passed into the contralateral lateral lemniscus and was distributed largely to its ventral nucleus. The caudal tip of the ipsilateral ventral nucleus of the lateral lemniscus received abundant degeneration, but this diminished rostrally.  

The resultant data indicate that the primary generator of potential is the acoustic nerve; of potential 2, the cochlear nucleus; of potential 3, neurons of the superior olivary complex activated by projections crossing the midline; of potential 4, neurons of the ventral nucleus of the lateral lemniscus and preolivary region activated equally by crossed and uncrossed projections; and of potential 5, neurons of the inferior colliculus activated primarily by crossed projections..  

The ventral nucleus of the lateral geniculate body had 5 major projections to brain stem structures both ipsilateral and contralateral to the injected nucleus.  

The ventral cochlear nucleus (VCN) projects via the trapezoid body to ipsilateral LSO, ipsilateral preolivary nuclei, ipsilateral lateral and a contralateral medial dendritic fields of MSO, and contralateral NTB; there is also a small ipsilateral projection to the ventral nucleus of the lateral lemniscus (VNLL) and the central nucleus of the inferior colliculus (CNIC).  


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