Superior Colliculus

With retrograde injection of fluorescent tracers into the Superior Colliculus, lateral geniculate body, or optic nerve, RGCs can be detected in vivo with confocal laser scanning microscopy, fluorescent microscopy, or confocal scanning laser ophthalmoscopy.  

This experiment examined the separate and combined effects of baclofen (5.0 mg/kg, i.p.), a GABA B receptor agonist, and ethanol (2.0 g/kg, i.p.) on flash-evoked potentials (FEPs) recorded from both the visual cortex and Superior Colliculus (SC) of chronically implanted male Long-Evans rats.  

Next, we evaluate the feasibility of using different lines of thy1::Clomeleon transgenic mice to image synaptic inhibition in several different brain regions: the hippocampus, the deep cerebellar nuclei (DCN), the basolateral nucleus of the amygdala, and the Superior Colliculus (SC).  

The network involved in pro-saccade generation (by definition largely exogenously-driven) includes subcortical (striatum, thalamus, Superior Colliculus, and cerebellar vermis) and cortical (primary visual, extrastriate, and parietal cortices, and frontal and supplementary eye fields) structures.  

At 23 days after the optic nerve crush, the retinal ganglion cells were retrogradely labeled by injecting 3% fluorogold into both sides of the Superior Colliculus of the brain.  

Among these are the roles of medial versus lateral posterior parietal cortex; cholinergic mechanisms in attention; interhemispheric interactions; the role of synchronous firing at the cortical, striatal, and thalamic levels; interactions between cortical and thalamic projections to the striatum; interactions between cortical and nigral inputs to the thalamus; the role of collicular inputs to the lateral posterior thalamic nucleus; the role of cerebral cortex versus Superior Colliculus in driving the motor output expressed as orienting behavior during directed attention; the extent to which the circuitry we describe for directed attention also plays a role in other forms of attention..  

How do multiple brain regions interact, including frontal cortical areas, to decide the choice of a target among several competing moving stimuli? How is target selection information that is created by a bias (e.g., electrical stimulation) transferred from one movement system to another? These saccade-pursuit interactions are clarified by a new computational neural model, which describes interactions between motion processing areas: the middle temporal area, the middle superior temporal area, the frontal pursuit area, and the dorsal lateral pontine nucleus; saccade specification, selection, and planning areas: the lateral intraparietal area, the frontal eye fields, the SNr, and the Superior Colliculus; the saccadic generator in the brain stem; and the cerebellum.  

Differential activations to fearful versus neutral faces were observed in the amygdala, pulvinar, and Superior Colliculus only for faces presented in the left hemifield.  

The purpose of this study, on mice, was to determine whether memantine, a glutamate-receptor antagonist of the N-methyl-(d)-aspartate (NMDA) subtype, protects against neuronal degeneration in the dorsal lateral geniculate nucleus (dLGN) and Superior Colliculus (SC) after the induction of retinal damage by intravitreal injection of NMDA.  

The primate Superior Colliculus (SC) has long been known to be involved in saccade generation.  

Constitutive and retina-specific p75(NTR) knockout mice have aberrant anterior shifts in retinal axon terminations in Superior Colliculus, consistent with diminished repellent activity mediated by graded ephrin-A reverse signaling induced by graded collicular EphAs.  

The onset and vector of orienting behaviors, such as saccades, are controlled by commands that descend from a population of neurons in deep layers of the Superior Colliculus (dSC). In this study, to characterize the role of the collicular local circuitry that generates the spatiotemporal pattern of command activity in the dSC neuronal population, responses evoked by single-pulse electrical stimulation in superficial layers of the Superior Colliculus (sSC) were analyzed by a 64-channel field potential recording system (planar electrode, 8 x 8 pattern; 150 microm interelectrode spacing) in slices obtained from 16- to 22-d-old mice.  

The MPL has afferent neuronal connections distinct from adjacent brain regions including major inputs from the auditory cortex, medial part of the medial geniculate body, Superior Colliculus, external and dorsal cortices of the inferior colliculus, periolivary area, lateral preoptic area, hypothalamic ventromedial nucleus, lateral and dorsal hypothalamic areas, subparafascicular and posterior intralaminar thalamic nuclei, periaqueductal gray, and cuneiform nucleus.  

With antibodies raised against the N-terminal mouse EAAT4 sequence, the highest protein expression levels were observed in the substantia nigra pars compacta, ventral tegmental area, paranigral nucleus, habenulo-interpeduncular system, supraoptic nucleus, lateral posterior thalamic nucleus, subiculum, and superficial layers of the Superior Colliculus.  

This study addresses this issue by quantifying the spatial relationships between visual and motor responses in the Superior Colliculus (SC), a midbrain structure involved in the transformation of visual information into saccadic motor command signals.  

Neurons in the intermediate gray layer (SGI) of mammalian Superior Colliculus (SC) receive cholinergic innervation from the brainstem parabrachial region, which appears to modulate the signal processing in the SC.  

In a different group of rats, retinal ganglion cells were retrogradely labeled by injecting Fluorogold in the Superior Colliculus a week before the induction of glaucoma.  

PRINCIPAL FINDINGS: Here we describe a Cre-transgenic line that allows reproducible expression of transgenic proteins of choice in a small number of neurons of the adult cortex, hippocampus, striatum, olfactory bulb, subiculum, hypothalamus, Superior Colliculus and amygdala.  

Specifically, we applied microstimulation in the superficial layers of Superior Colliculus (SC) to test for orthodromic activation of pulvinar neurons receiving input from SC.  

The cerebellar oculomotor vermis (OMV) receives inputs from both the Superior Colliculus (SC) via the nucleus reticularis tegmenti pontis as mossy fibres and the inferior olive as climbing fibres.  

We compared the activity of neurons in the Superior Colliculus (SC) and the cortical frontal eye field (FEF) during the majority of trials that were accomplished with single-step saccades with those completed with two-step saccades.  

Superior Colliculus (SC), 2.  

Whereas the rostral part of the Superior Colliculus (SC) is considered to be involved in visual fixation, the caudal part of the SC plays an important role in generation of saccades.  

Moreover, OPN4-dependent sleep regulation was correlated with the activation of sleep-promoting neurons in the ventrolateral preoptic area and the Superior Colliculus.  

These cells can be classified as cells projecting to the Superior Colliculus and melanopsin-containing retinal ganglion cells, which project to the suprachiasmatic nucleus. Superior collicular retinal ganglion cells were retrogradely labeled from the Superior Colliculus with Fluorogold.  

We recorded the activity of identified DLPFC-Superior Colliculus (SC) projection neurons while monkeys performed a memory-guided saccade task in which they were required to generate saccades toward remembered stimulus locations.  

We find that tOFF-alphaRGCs project exclusively to the Superior Colliculus (SC) and dorsal lateral geniculate nucleus and are restricted to a specific laminar depth within each of these targets.  

Here, we exploited differences in behavioural strategy to explore the role of the intermediate and deep layers of the Superior Colliculus (dSC) in covert orienting.  

The primate Superior Colliculus (SC) is often viewed as composed of two distinct motor zones with complementary functions: a peripheral region that helps generate saccades to eccentric targets and a central one that maintains fixation by suppressing saccades.  

For comparison, we also recorded from small groups of neurons in the superficial Superior Colliculus (supSC), an area that receives direct retinal input.  

This study aimed to test the hypothesis that visual responses in the Superior Colliculus (SC) originate from synaptic connections between fetal retinal transplants and degenerating host retinas.  

Neurons in the Superior Colliculus (SC) integrate stimuli of different modalities.  

Brain stem signals that generate saccadic eye movements originate in the Superior Colliculus.  

Populations of either Schwann cells or OEG were mixed with dissociated fetal tectal cells presumptive Superior Colliculus and, after reaggregation, pieces were grafted onto newborn rat Superior Colliculus. In control rats that received pure dissociatedreaggregated tectal grafts, retinal ganglion cell RGC axons selectively innervated defined target areas, corresponding to the retinorecipient layer in normal Superior Colliculus.  

Retinal input to a primary visual center, the Superior Colliculus (SC), is bilateral with a dense contralateral projection and a sparse ipsilateral one. Electrophysiological recording demonstrated that topography of visually evoked responses recorded from the contralateral Superior Colliculus of ephrin-A(-/-) mice displayed similar functional disorder in all genotypes, contrasting with their different degrees of anatomical disorder.  

Recently, we showed that the total synaptic input onto individual neurons of the mouse Superior Colliculus is preserved regardless of the size of their visual receptive fields, a phenomenon we term 'response homeostasis'.  

Two pathways from the Superior Colliculus (SC) to the tree shrew pulvinar nucleus have been described, one in which the axons terminate in dense (or specific) patches and one in which the axon arbors are more diffusely organized (Luppino et al.  

We suggest that the STN mediates the control signal originated from the medial frontal cortex and implements the behavioral switching function using its connections with other basal ganglia nuclei and the Superior Colliculus..  

Here, we examine the role of BMP and a potential downstream effector, EphB, in retinotopic map formation in the lateral geniculate nucleus (LGN) and Superior Colliculus (SC).  

Both the partial blockade of inputs to 50% of retinal ganglion cells by a mGluR6 glutamate agonist and the complete blockade of all retinal ganglion cell activity with tetrodotoxin failed to decrease the relative enhancement in the Superior Colliculus.  

In the brain, moderate Wfs1 expression was observed in the zonal, superficial gray, and intermediate gray layers of the Superior Colliculus, in the dorsomedial part of the suprachiasmatic nucleus, and in layer II of the primary and secondary visual cortices.  

These findings suggest that the Superior Colliculus, which is activated following threat perception, shows clear visual-field asymmetry, receives no direct S-cone-based inputs from the retina, and forms part of a hypothesized direct brainstem-amygdala-cortex alarm system, mediates this effect..  

RGC density was counted by retrograde labeling with FluoroGold application to the Superior Colliculus, and visual function was assessed by flash visual evoked potentials (FVEP).  

To answer this question, we recorded single-neuron activity in the Superior Colliculus (SC) as macaque monkeys performed a visually guided, asymmetrically rewarded saccade task.  

Optic nerves (ON) and Superior Colliculus (SC) segments were processed for electron microscopy (EM) and immunoelectron microscopy (IEM) for NF subunits.  

GLY given in the deep layer of Superior Colliculus did not produce changes in tail-flick latencies.  

Function was monitored serially by measuring acuity (using an optomotor test) and luminance thresholds (recording from the Superior Colliculus) at approximately P90, P150, and P280.  

The direct projection from the substantia nigra pars reticulata (SNr) to the Superior Colliculus (SC) mediates the inhibition.  

SIGNIFICANCE: These results are likely explained by alteration of the information processed by the Superior Colliculus (SC), a pivotal visuomotor structure involved in both voluntary and reflexive saccades.  

High non-AT1, non-AT2 binding site density is present in brain regions containing high levels of the AT2 Ang II receptor subtype (amygdala, several thalamic nuclei, Superior Colliculus).  

This study tested the role of the Superior Colliculus in generating movements of the mystacial vibrissae--whisking. First, we compared the kinematics of whisking generated by the Superior Colliculus with those generated by the motor cortex. Movements generated by the Superior Colliculus are independent of motor cortex and can be evoked at lower thresholds and shorter latencies than those generated by the motor cortex. Together these findings suggest that the Superior Colliculus plays a pivotal role in vibrissa movement--regulating vibrissa set point and whisk amplitude--but does not function as a simple reflex loop. With the motor cortex controlling the whisking frequency, the Superior Colliculus control of set point and amplitude would account for the main parameters of voluntary whisking..  

We summarize our research findings from behavioral studies of echolocating bats engaged in natural tasks and from neurophysiological studies of the bat Superior Colliculus and hippocampus, brain structures implicated in sensorimotor integration, orientation, and spatial memory.  

A candidate pathway for providing CD for vision ascends from the Superior Colliculus to the frontal cortex in the primate brain.  

During the first 2 weeks of postnatal development, numerous GATA3-expressing cells were found in the intergeniculate leaf, ventral lateral geniculate nucleus, pretectal nucleus, nucleus of the posterior commissure, Superior Colliculus, inferior colliculus, periaqueductal grey, substantia nigra and raphe nuclei.  

The cMRF receives projections from the ipsilateral Superior Colliculus (SC) via collaterals of predorsal bundle axons.  

High-density specific binding was found in discrete areas of the brain and spinal cord, namely in the limbic system (hippocampal formation, septohippocampal nucleus, indusium griseum, hypothalamus, amygdaloid nuclei), Superior Colliculus, dorsal raphé, and substantia gelatinosa of the spinal cord.  

Cell death, measured by Fluoro-jade B and activated caspase-3, was significantly increased at 12 and 24 hour post-caffeine injection (P < 0.05) in the cortex, caudate, nucleus accumbens, hypothalamus, hippocampus and Superior Colliculus.  

Pax7 mutant mice, however, present with no obvious morphological impairments to the Superior Colliculus. RESULTS: Analysis of the Superior Colliculus of Pax7 mutant and wildtype mice at a variety of developmental timepoints revealed that whilst correct initial specification is maintained, a subpopulation of dorsal mesencephalic neurons is lost at early postnatal stages.  

These observations have typically been attributed to the anatomical asymmetry of fibres projecting to the Superior Colliculus (SC), even though this attribution is debated.  

Given ocular stability, low-frequency activity sustained by some neurons within the intermediate and deep Superior Colliculus (dSC) is assumed to be separated from motor output.  

Here, we consider recent experiments that identified a pathway for a corollary discharge for saccades that extends from the Superior Colliculus in the midbrain to the frontal eye fields in the cerebral cortex with a relay in the medial dorsal nucleus of the thalamus.  

This was first discovered in the Superior Colliculus of the monkey: neurons in the superficial layers of the Superior Colliculus responded more intensely to the onset of a stimulus during blocks of trials in which the monkey had to make a saccade to it than they did during blocks of trials in which the monkey had to continue fixating a central point and not respond to the stimulus.  

Recently, we proposed an ensemble-coding scheme of the midbrain Superior Colliculus (SC) in which, during a saccade, each spike emitted by each recruited SC neuron contributes a fixed minivector to the gaze-control motor output.  

Sensory integration is a characteristic feature of Superior Colliculus (SC) neurons.  

Nitric oxide (NO) containing (nitrergic) interneurons are well-positioned to convey the cortical influences that are crucial for multisensory integration in Superior Colliculus (SC) output neurons.  

Such naso-temporal asymmetry (NTA) has been assumed to reflect the asymmetry in the retinotectal pathway to the Superior Colliculus.  

Neurons in the Superior Colliculus (SC) are known to integrate stimuli of different modalities (e.g., visual and auditory) following specific properties.  

Ob rats showed greater changes with FS than Le rats (deactivation of hippocampus and activation of the medial thalamus) and Ob but not Le animals deactivated the frontal cortex and activated the Superior Colliculus. The main changes with FS occurred in the hippocampus, a region involved in memory, the insular cortex, a region involved with interoception (perception of internal sensations), the medial thalamus (region involved in alertness) and in regions involved with sensory perception (olfactory bulb, olfactory nucleus, occipital cortex, Superior Colliculus and parietal cortex), which corroborates their relevance in the perception of food..  

In both postnatal and adult brains, ERRbeta immunoreactive fibers were distributed in a pattern which perfectly matched the retinal efferent projections: optic tract, supraoptic commissure, hypothalamic suprachiasmatic nucleus, ventral and dorsal geniculate nuclei, pretectal nuclei, and Superior Colliculus.  

We measured the initial visual activity of Superior Colliculus (SC) neurons in response to the appearance of these targets.  

A high density of calcitonin gene-related peptide-immunoreactive perikarya was found in the Superior Colliculus, the dorsal nucleus of the raphe, the trochlear nucleus, the lateral division of the marginal nucleus of the brachium conjunctivum, the motor trigeminal nucleus, the facial nucleus, the pons reticular formation, the retrofacial nucleus, the rostral hypoglossal nucleus, and in the motor dorsal nucleus of the vagus, whereas a high density of fibers containing calcitonin gene-related peptide was observed in the lateral division of the marginal nucleus of the brachium conjunctivum, the parvocellular division of the alaminar spinal trigeminal nucleus, the external cuneate nucleus, the nucleus of the solitary tract, the laminar spinal trigeminal nucleus, and in the area postrema.  

Similar effects were obtained with GR 82334 infusion into the ventromedial nucleus of the hypothalamus (VMH), to which the MeA projects, and into the rostral dorsolateral periaqueductal gray (PAG), to which the VMH projects, but not into the deep layers of the Superior Colliculus/deep mesencephalic nucleus (dSC/DpMe), an output of the CeA previously shown to be important for fear-potentiated startle.  

Activated brain regions included the primary and secondary visual cortex, Superior Colliculus (SC), dorsal lateral geniculate (DLG), and lateral posterior nucleus (LP), which were found to exhibit differing temporal responses.  

Anterograde tracer experiments in the sensory trigeminal complex (STC) explored the trigemino-coerulear connection; retrograde tracer experiments in the latero-caudal portion of the Superior Colliculus (SC) established coerulear-collicular connections.  

We also studied the effects of tryptophan restriction on 5-HT immunoreactivity of raphe neurons, on cAMP levels in the visual layers of the Superior Colliculus and on protein synthesis among retinal neurons. Tryptophan restriction was also associated with a reduction of serotonin immunoreactive cells in the raphe nuclei and increased cAMP levels in the Superior Colliculus.  

The reduction in microglial activation was coupled to significant improvement in RGC axonal transport, as measured by neuronal retrograde tracing from the Superior Colliculus.  

Moreover, the results show that the preparation manual responses tend to mediate saccadic behavior-but only when the manual responses require high levels of spatial accuracy-and that the Superior Colliculus is the likely neural substrate integrating IOR for eye and arm movements..  

in the Superior Colliculus, the suprageniculate nucleus and the anterior ectosylvian cortex, but differ strongly from those of the primary visual cortex and the lateral geniculate nucleus.  

On the whole, endogenous saccade generation appears facilitated by emotional target content, probably via increased input from extra-striate and parietal brain areas to the Superior Colliculus.  

Recent evidence indicates that inactivation of the primate Superior Colliculus (SC) results in an increase in saccade target-selection errors.  

Here, we apply an SDT framework to a motor system by recording from Superior Colliculus (SC) neurons during performance of a color, oddball selection task.  

We localized calbindin D28K-immunoreactive (IR) neurons in the Superior Colliculus (SC) of the dog and studied the distribution and effect of enucleation on the distribution of this protein.  

In mesencephalon, strong immunoreactivity was detected in Superior Colliculus, inferior colliculus and paramedian raphe nucleus.  

BACKGROUND: Each Superior Colliculus receives optic nerve fibers primarily from the contralateral eye, and visual input to each colliculus activates the ipsilateral hemisphere.  

RGCs were quantified in retinal flatmounts after postischemic injection of tracer into the Superior Colliculus.  

Stimulation and recording data have implicated the primate Superior Colliculus (SC) in the control of these gaze shifts.  

This neural site is probably the Superior Colliculus (SC), because an RSE explainable by neural coactivation does not occur with purple or blue stimuli, which are invisible to the SC; such an RSE only occurs for spatially and temporally coincident audiovisual stimuli, in strict adherence with the multisensory responses in the SC of the cat.  

Intense Atrn expression was also observed in the neuropil of gray matter in many regions of the CNS, such as the main and accessory olfactory bulb, cerebral cortex, caudate putamen, dorsal lateral geniculate nucleus, medial eminence, Superior Colliculus, hippocampus, dentate gyrus, and layers 1 and 2 of the spinal cord.  

Their mechanism of action in this regard is unknown, however one possibility is that the drugs affect the Superior Colliculus (SC), a structure with a clearly defined role in distractibility.  

Single units in the intermediate and deep layers of the Superior Colliculus were recorded using moveable microelectrodes.  

The cortical activation was distributed over the cingulate, motor, somatosensory, insular, and visual cortices, and the subcortical activation involved the caudate putamen, hippocampus, periaqueductal gray, Superior Colliculus, thalamus, and hypothalamus.  

RESULTS : The SPM analysis showed that the rCBF of the IGE patients was significantly reduced in the anterior and posterior cingulate gyri, bilateral anterior nuclei and right dorsolateral nucleus of the thalamus, right Superior Colliculus of the midbrain, and the cerebellum at the level of uncorrected p < 0.005.  

The ventral lateral geniculate nucleus (vLGN), the pretectal nuclear complex (PNC) and the Superior Colliculus (SC) are structures that all receive retinal input.  

Here, as a first approach to gain more insight on the role of two MAPKs - ERK1/2 and p38(MAPK) - in visual system maturation, we characterized by western blot the regulation of their phosphorylation/activation in rat retina, Superior Colliculus and visual cortex, during postnatal development from birth to adult age. Our main results show that: (i) in the retina p38(MAPK) activation peaks at P4, and then, from P15 to P45, both ERK1/2 and p38(MAPK) phosphorylation increases; (ii) in the Superior Colliculus phosphorylation of both MAPKs increases between P4 and P15; (iii) in the visual cortex ERK1/2 phosphorylation increases from P15 to P45, while phosphorylation of p38(MAPK) increases starting from P4.  

The rostral part of the dorsal midbrain, known as the Superior Colliculus in mammals or the optic tectum in birds, receives a substantial retinal input and plays a diverse and important role in sensorimotor integration.  

We found the connections normally described in the ZRDCT/An mouse between: (i) the inferior colliculus and the dorsal lateral geniculate nucleus, (ii) V1 and the Superior Colliculus, (iii) the lateral posterior nucleus and V1 and between (iv) the inferior colliculus and the medial geniculate nucleus.  

Here we demonstrate that the human pulvinar is interconnected with subcortical structures (Superior Colliculus, thalamus, and caudate nucleus) as well as with cortical regions (primary visual areas (area 17), secondary visual areas (area 18, 19), visual inferotemporal areas (area 20), posterior parietal association areas (area 7), frontal eye fields and prefrontal areas).  

Axons of retinal ganglion cells form the optic nerve and innervate areas of the brain important for visual processing, including the lateral geniculate nucleus, the Superior Colliculus, and the pretectal nucleus.  

Much of the information about multisensory integration is derived from studies of the cat Superior Colliculus (SC), a midbrain structure involved in orientation behaviors.  

The Superior Colliculus (SC) has been implicated in the mediation of residual visual function in hemianopic patients, and has been shown to be capable of using multiple sensory cues to facilitate its localization functions. A likely explanation of these differences is that enhancement and visual bias depend on different neural pathways: with the former dependent on circuits involving the Superior Colliculus, a structure involved in the integration of cues from multiple senses to facilitate orientation/localization; and the latter dependent on geniculo-striate circuits that facilitate more detailed analyses of the visual scene.  

SPIG1-positive RGCs in the dorsotemporal domain project to the dorsal lateral geniculate nucleus (dLGN), Superior Colliculus, and accessory optic system (AOS).  

Autoradiographic distribution of GPCR135 binding sites using [ 125 I]R3/I5 in rat brain shows that GPCR135 receptor is prominent in many regions, including olfactory bulb, amygdala, thalamus, somatosensory cortex, and Superior Colliculus, which have been reported to have connections to the nucleus incertus.  

The auditory cortex connects with visual areas and with the Superior Colliculus.  

How are stimulus-driven reflexes generated, and what controls their competition with voluntary action? The saccadic reflex to look towards an abrupt visual onset (prosaccade) has been associated with the retinotectal and magnocellular pathways, which rapidly convey signals to the Superior Colliculus and cortical eye fields. Furthermore, signals recorded from the Superior Colliculus showed the reverse pattern of responses, consistent with a direct inhibitory influence of IPS on SC..  

Additional concentrations are present in the parabrachial nuclei and Superior Colliculus.  

The current study sought to determine how neuronal activity in the intermediate layers of the Superior Colliculus (SC) determines correct saccade target selection by examining the activity of visuomovement neurons during both correct and error trials of monkeys performing a relatively difficult visual conjunction search task.  

In the present study, we investigated the functions of I(h) in the motion-sensitive projection neurons [ wide field vertical (WFV) cells] of the Superior Colliculus, a pivotal visual center for detection of and orientating to salient objects. Combination of whole cell recordings and immunohistochemical investigations suggested that HCN1 channels dominantly contribute to the I(h) in WFV cells among HCN isoforms expressed in the superficial Superior Colliculus and mainly located on their expansive dendritic trees.  

In slice preparations, electrical stimulation of the superficial gray layer (SGS) of the Superior Colliculus (SC) induces EPSC bursts in neurons in the intermediate gray layer (SGI) when GABA(A) receptor (GABA(A)R)-mediated inhibition is reduced.  

Here, we hypothesise (Hypothesis 1) that one such locus is the Superior Colliculus (SC), a sensory structure intimately linked with distractibility and the production of eye and head movements.  

Thus, the presence of a cMRF that supplies gaze-related feedback to the Superior Colliculus may be a common vertebrate feature.  

Spatial frequency was measured by recording optomotor responses at P100 and P150, and luminance threshold responses were recorded from the Superior Colliculus at P150.  

During development, spontaneous retinal waves are thought to provide an instructive signal for retinotopic map formation in the Superior Colliculus.  

To investigate a role for L1 association with the cytoskeleton in topographic guidance of retinal axons to the Superior Colliculus, a novel mouse strain was generated by genetic knock-in that expresses an L1 point mutation (Tyr1229His) abolishing ankyrin binding. Axon tracing revealed a striking mistargeting of mutant ganglion cell axons from the ventral retina, which express high levels of ephrinB receptors, to abnormally lateral sites in the contralateral Superior Colliculus, where they formed multiple ectopic arborizations.  

The present study aimed at investigating the effects of early visual deprivation (bilateral neonatal enucleation) on auditory and somatosensory coding in the polysensory deep layers of the Superior Colliculus of the rat.  

The thalamic lateral posterior nucleus (LP) of the hooded rat is regarded as a relay nucleus for the transmission of information from visuomotor-related structures such as the Superior Colliculus, pedunculopontine tegmental nucleus (PPT) and substantia nigra, pars reticulata, to visual cortical areas as well as the striatum.  

In the visual layers of NR2A-/- juvenile Superior Colliculus (SC), synapses lose miniature NMDAR currents, leaving NR2B-rich receptors in extrasynaptic regions.  

We study the consequences of input background activity on simulated self-organization, using the SOM, of the retinotopic map in the Superior Colliculus.  

OBJECTIVE: During postnatal development, retinotectal projections undergo a process of misplaced axon elimination, leading to a topographical matching between the retinal surface and the Superior Colliculus. MATERIAL AND METHODS: Lister hooded rats at different postnatal ages received subpial ethylene vinyl acetate 40W implants to deliver an MMP inhibitor or vehicle to the Superior Colliculus.  

A dopamine release during involuntary attention is promoted by visual activation of striatonigral cells via the thalamus and subsequent disinhibition through the basal ganglia of the Superior Colliculus.  

Here, we demonstrate that primate neck muscles are recruited during such reflexive covert orienting in a manner that parallels activity recorded from the Superior Colliculus (SC).  

Multiunit luminance thresholds were recorded in the Superior Colliculus after CNTF injection, and the eyes were examined histologically. When measured in the Superior Colliculus at 2 weeks after CNTF injection, luminance thresholds were elevated by 0.35 log units.  

The Superior Colliculus (SC) is generally believed to be critically involved in generating both effects.  

It occupies what has traditionally been considered the most medial region of the deep Superior Colliculus and the most medial region of the inferior colliculus.  

Converging cortical influences from the anterior ectosylvian sulcus and the rostral lateral suprasylvian sulcus were shown to have a multisensory-specific role in the integration of sensory information in Superior Colliculus (SC) neurons.  

Following 2 h of drug administration, it showed that olanzapine administration significantly decreased PYY binding densities, predominantly in the posterodorsal part of medial amygdaloid nucleus (52%, p<0.05), dorsal part of medial geniculate nucleus (56%, p<0.05), superficial gray layer of the Superior Colliculus (53%, p<0.05), parabrachial pigmented nucleus (54%, p<0.05) and periaqueductal gray (50%, p<0.05) compared to controls, while rebound increases of PYY binding densities were observed in most of examined regions 48 h later with only medial geniculate nucleus dorsal showing significant increase compared to controls (118%, p<0.01). Alterations in PYY binding densities in brain regions such as the dorsal part of medial geniculate nucleus, superficial gray layer of Superior Colliculus, periaqueductal gray and parabrachial pigmented nucleus may represent the specific regions that mediate the clinical effects of antipsychotics via neuropeptide Y system.  

Animal studies have shown that the Superior Colliculus (SC) is important for synthesising information from multiple senses into a unified map of space.  

The ability of cat Superior Colliculus (SC) neurons to integrate information from different senses is thought to depend on direct projections from regions along the anterior ectosylvian sulcus (AES).  

Visually evoked responses to varying light intensities were recorded from the Superior Colliculus (SC) by electrophysiology at 60days after surgery.  

The visual system is well developed but exceeded by the robust auditory system; for example, the inferior colliculus is several times larger than the Superior Colliculus.  

Additional significant changes were noted in the ventral pallidum, Superior Colliculus, dentate gyrus (increases), and red nucleus (decreases).  

Among the regions of brain we surveyed, the alpha5 subunit is associated in approximately 37% of the nAChRs in the hippocampus, approximately 24% of the nAChRs in striatum, and 11-16% of the receptors in the cerebral cortex, thalamus, and Superior Colliculus.  

In the present work, we reviewed critically current data about nitric oxide synthase (NOS) expression in the Superior Colliculus/optic tectum, as well as the roles of NO in the formation of the retinotopic map and in synaptic plasticity.  

These results suggest a functionally intact, albeit unconscious, projection to the dorsal pathway that bypasses V1 and implicates a functional input into the dorsal stream from the Superior Colliculus..  

One hour stimulation was performed in the rat retina and electrically evoked responses in the Superior Colliculus were recorded before and after the continuous stimulation.  

We investigated this question by recording from single neurons in the macaque Superior Colliculus (SC) while the animal was performing a memory-guided saccade task with an asymmetrical reward schedule.  

Based on the measured properties of these cells, we speculate that they correspond to the smooth/large radiate cells recently identified morphologically in the primate retina and may therefore provide visual input to both the lateral geniculate nucleus and the Superior Colliculus.  

Ultimately, the spontaneous activity in PBN neurons could be used to modulate cholinergic drive in the Superior Colliculus in either positive or negative directions..  

Selected rats (n = 5) were subjected to electrophysiologic evaluation of visual responses from the Superior Colliculus about 84-121 days after surgery. RESULTS: All the transplanted rats that were evaluated for visual responses in the brain showed responses to very low light stimulation (-3.42 to -2.8 log cd/m(2)) of the eye in a small area of the Superior Colliculus corresponding with the placement of the transplant in the host retina.  

Inhibitory pathways project from the pretectal nuclear complex to the ipsilateral Superior Colliculus (SC) and dorsal lateral geniculate nucleus (dLGN).  

METHODS: Apoptotic RGC death was induced in neonates by removal of the contralateral Superior Colliculus (SC) and in adults by unilateral optic nerve transection, with or without a peripheral nerve (PN) graft.  

Auditory evoked potentials indicated a left-side lesion between superior olivary nucleus and Superior Colliculus.  

Damage to the projections from the Superior Colliculus to omnipause neurons and resultant dysfunction of omnipause neuron may be a mechanism of saccadic intrusions and oscillations observed in our patient with a circumscribed brainstem lesion..  

We provide here, for the first time, a theory involving the motor function of the Superior Colliculus to explain the geometry of its maps.  

The present findings show the anticonvulsant action of fluoxetine is markedly attenuated following the loss of midbrain 5-HT, particularly in the region of the Superior Colliculus, while forebrain and spinal cord 5-HT do not appear to play a role in the action of fluoxetine.  

It has been suggested that this inhibition-rebound response is a type of oculomotor reflex mediated by the Superior Colliculus (SC), a midbrain structure involved in saccade programming.  

Animals trained to detect an electrical somatosensory stimulus delivered to the whisker pad in an active avoidance task were able to detect this CS and perform the task when a reversible or irreversible lesion was placed in either the somatosensory thalamus or the Superior Colliculus contralateral to the CS. However, simultaneous lesions of the somatosensory thalamus and Superior Colliculus contralateral to the CS blocked performance in the active avoidance task. In contrast, a lesion only of the somatosensory thalamus contralateral to the same CS, but not of the Superior Colliculus, blocked performance in a pavlovian fear conditioning task. During active avoidance conditioning, a situation in which the aversive outcome is contingent on the behavior of the animal (i.e., the animal can avoid the aversive event), the sensory thalamus and the Superior Colliculus function as alternative routes for CS detection.  

In the visual system, PSA-NCAM participates in retinal ganglion cell (RGC) axon growth during development and specifically influences RGC innervation of its principle target tissue, the Superior Colliculus (SC).  

Since the Superior Colliculus (SC) is implicated in the neuronal network of audiogenic seizures (AGS) in other forms of AGS, this study evaluated seizure-related anatomical or neurochemical abnormalities in the SC of the GPG/Vall hamster.  

Because neuronal activity in the Superior Colliculus and downstream oculomotor areas has been shown to correlate with saccadic peak velocity, our findings support the notion that a reafferent extraretinal signal associated with saccadic motor commands may contribute to perisaccadic compression of perceived positions..  

These results resemble neck EMG evoked from the Superior Colliculus (SC).  

The spatial extent of retinal input to the developing hamster Superior Colliculus (SC) can be experimentally increased by chronic NMDA receptor (NMDAR) blockade.  

There is considerable support for the hypothesis that visual stimuli can access the amygdala via a pathway that includes the Superior Colliculus and the pulvinar nucleus of the thalamus.  

In particular, we will focus on the nAChRs present in the visual pathway (retina, Superior Colliculus and nucleus geniculatus lateralis), in which neurons express most, if not all, nAChR subunits.  

In the present study, single-unit extracellular activity was recorded from the Superior Colliculus while monkeys performed behavioral tasks that permit the temporal dissociation of gaze shifts and head movements. We sought to determine whether Superior Colliculus contains neurons that modulate their activity in association with head movements in the absence of gaze shifts and whether classic gaze-related burst neurons also discharge for head-only movements. These results suggest the possibility that the Superior Colliculus plays a role in the control of head movements independent of gaze shifts..  

A possible benefit has been postulated because of the connections that exist between the subthalamic nucleus (STN) and the Superior Colliculus.  

Area 7m is a parietal area anatomically connected with oculomotor structures such as frontal eye field and Superior Colliculus.  

Based on their data and clinical observations, they proposed that the rostral pole of the Superior Colliculus has a critical role in the control of accommodation, vergence, and fixation.  

The model also predicts the receptive field properties of Superior Colliculus neurons that are involved in these behaviors, and sheds new light on the computational responsibilities different circuits have in effecting these behaviors.  

Individual Superior Colliculus (SC) neurons integrate information from multiple sensory sources to enhance their physiological response.  

The central mesencephalic reticular formation (cMRF) and paramedian pontine reticular formation (PPRF) are two brain stem regions that likely participate in the development of motor activity since both structures are anatomically connected to nuclei that encode movement goal (Superior Colliculus) and generate horizontal eye movements (abducens nucleus).  

We found that dark-rearing was associated with a reduction in the distribution of retinal fibers in the stratum opticum of the contralateral Superior Colliculus. A decrease in retinal innervation of the stratum opticum and intermediate layers of the Superior Colliculus may account for some of the deficits in multisensory integration that have been observed in dark-reared animals of several species..  

We tested the possibility that the residual IT is mediated by the collicular commissure interconnecting the two sides of the Superior Colliculus (SC).  

As the optic tectum of nonmammals is homologous to the Superior Colliculus of mammals, the analysis of the tectal and collicular proteome may provide clues about conserved cell and circuit layout, circuit function, and evolution..  

Motor preparation and visual signals converge in the intermediate and deep layers of the Superior Colliculus (SC) to influence saccade planning and execution; however, the mechanism by which these sometimes conflicting signals are combined remains unclear.  

The neural organization of the pathways from the Superior Colliculus (SC) to trochlear motoneurons was analyzed in anesthetized cats using intracellular recording and transneuronal labeling techniques.  

The uppermost layer (stratum griseum superficiale, SGS) of the Superior Colliculus (SC) provides an important gateway from the retina to the visual extrastriate and visuomotor systems.  

Quantitative autoradiography with [ (125)I]alpha-conotoxin MII to selectively label alpha6(*) nAChRs showed a 28% decrease in binding in the striatum but no change in the Superior Colliculus. In contrast, chronic nicotine caused a 39% decrease in alpha6-containing nAChRs in striatum but no change in Superior Colliculus.  

In this article, we present a neural model of saccade initiation based on competitive integration of planned and reactive saccade decision signals in the intermediate layer of the Superior Colliculus.  

Discrete injections of fluorescent beads in the Superior Colliculus followed by isodensity contour analysis of labelled retinal cells reveals a dramatic decrease in the extent of retina labelled between postnatal days 2, 6 and 12 (P2, P6, P12): the 20% contour encloses 38.3%, 8.3% and 1.8% of the retina at these ages.  

One possible locus for such saccade adaptation is the Superior Colliculus (SC), the relay for cortical commands to the premotor brain stem generator for saccades.  

These nuclei provide cortico-pulvinar-cortical interactions that spread information across areas within streams, as well as information relayed from the Superior Colliculus via inferior pulvinar nuclei to largely dorsal stream areas..  

We assumed that the saccade latency decreases at the expense of the involvement of the main oculomotor areas of motor and saccadic planning in its initiation; an express saccade can be initiated also by means of direct transmission of the signal from the cortex to the brainstem saccadic generator passing by the Superior Colliculus.  

The spatio-temporal frequency response profiles of 73 neurons located in the superficial, retino-recipient layers of the feline Superior Colliculus (SC) were investigated.  

Neurons in the superficial gray layer (SGS) of the Superior Colliculus receive visual input and excite intermediate layer (SGI) neurons that play a critical role in initiating rapid orienting movements of the eyes, called saccades.  

Unilateral inactivation of the Superior Colliculus causes profound neglect. We made muscimol injections into one Superior Colliculus, and performed perimetry to gauge the extent of the cat's neglect.  

This experiment examined the effects of the GABA-B agonist baclofen on flash-evoked potentials (FEPs) recorded from both the visual cortex (VC) and Superior Colliculus (SC) of chronically implanted male Long-Evans rats.  

Principal outcomes were quantified using electroretinography, visual acuity measurements and luminance threshold recordings from the Superior Colliculus.  

The pattern of stimulation effects suggests that SNr influence is widespread, altering the pattern of activity bilaterally across the Superior Colliculus map of saccades..  

These specializations were utilized by investigating the mammalian Superior Colliculus (SC); a midbrain sensory motor nucleus mediating orientating behaviours in mammals, including vocal motor orientating.  

Other mesencephalic expression sites were the Superior Colliculus, periaqueductal gray, paramedian raphe nucleus, and inferior colliculus.  

We previously had shown that: (1) serial GABAergic connections from the CD to the Superior Colliculus (SC) via the substantia nigra pars reticulata (SNr) exert powerful control over the initiation of saccadic eye movement and (2) these GABAergic neurons encode target position and are strongly influenced by expected reward, while dopaminergic neurons in the substantia nigra pars compacta (SNc) encode only reward-related information.  

Some researchers speculate that the neural basis of such face perception is the subcortical network, comprised of the amygdala, the Superior Colliculus, and the pulvinar.  

To identify the cells at the time of the recording experiments, they were prelabeled by retrograde axonal transport of WGA-apo-HRP-gold (15 nm), which was injected into their primary projection targets, either the ipsilateral Superior Colliculus (iSC), or the contralateral NOT (cNOT), or the ipsilateral inferior olive (iIO).  

Using Superior Colliculus neurons as a model, it was found that multisensory integration of cross-modal stimulus combinations yielded responses that were significantly greater than those evoked by the best component stimulus.  

The purpose of this study is to: (1) examine the relative contributions of the 13 acoustically-responsive regions of the cerebral cortex to sound localization; (2) examine the laminar contributions to spatial localization behavior for each of the cortical areas identified to be critical for accurately determining the position of a sound source; and (3) synthesize the findings from sound localization studies and the underlying corticocortical and corticotectal connections to develop a processing system for sound localization information within and between the cerebral cortex and the Superior Colliculus. In turn, neurons in the deeper layers of AES project to the intermediate and deeper layers of the Superior Colliculus. Therefore, we propose that sound localization signals processed in primary and non-primary auditory cortex are transmitted to the Superior Colliculus by means of the auditory field of the AES..  

During development, gradients of EphA receptors (nasal(low)-temporal(high)) and their ligands ephrin-As (rostral(low)-caudal(high)) are involved in establishing topography between retinal ganglion cells (RGCs) and the Superior Colliculus (SC).  

We studied calretinin-immunoreactive (IR) fibers and cells in the canine Superior Colliculus (SC) and studied the distribution and effect of enucleation on the distribution of this protein.  

The standards for comparison (PE2I and FETT) competed strongly in all regions investigated (striatum, cortex, Superior Colliculus and cerebellum).  

The decrease of [ (18)F]fluoroxanomeline uptake in M2 knockout mice reached statistical significance in brain stem, cerebellum, frontal cortex, hippocampus, inferior colliculus and Superior Colliculus.  

Although the rat is widely used in neurobehavioural research, the spatio-temporal receptive field properties of neurons in superficial layers of the Superior Colliculus are relatively unknown.  

The transcription factor Pax7 has been implicated in the normal development of the Superior Colliculus and continues to be expressed in the adult Superior Colliculus, where it is concentrated in the retino-recipient laminae. Here we assessed, immunohistochemically, Pax7 expression in the adult rat Superior Colliculus after unilateral intraorbital optic nerve transection. We show that after optic nerve transection, the number of Pax7-expressing cells increased to re-establish the developmental rostral-caudal gradient and that these Pax7-expressing Superior Colliculus cells were neurons.  

In vivo recordings reveal that neurons in the Superior Colliculus of beta2-/- mice have large receptive fields and low peak visual responses, resulting in a conservation of total integrated response.  

Ensuing cell death in the retina and Superior Colliculus was analyzed by using the Feulgen method. In contrast, the presence of this antagonist induced a significant increase in the number of apoptotic cells in the neuroblastic layer (P7 and P8) and ganglion cell layer (P6-P8), as well as in the Superior Colliculus which receives afferent contacts from retinal ganglion cells during P7-P9.  

Freezing behavior induced by intra-ICd NMDA caused an increase of Fos expression in the MGN, Superior Colliculus, dorsal columns of the periaqueductal gray and locus coeruleus while freezing induced by intra-ICv NMDA caused a significant Fos immunoreactivity in the prelimbic (PrL) and cingulate (Cg) cortices, basolateral and medial nuclei of the amygdala, ventrolateral periaqueductal gray, cuneiform nucleus and locus coeruleus.  

Nicotine induced c-fos expression in the bed nucleus of the stria terminalis, the central nucleus of the amygdala (CeA), nucleus accumbens, and the Superior Colliculus (SC) at both ages, whereas it activated the hypothalamic paraventricular nucleus (PVN) and consequent corticosterone secretion only in adults.  

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