Superficial Layer Of Superior Colliculus

Surround inhibition shapes velocity tuning in the majority of superficial layer SC neurons in normal hamsters.  

In addition, intense BMP4 expression was also observed in the neuropil of the gray matters where high plasticity is reported, such as the molecular layer of the cerebellum and the superficial layer of the superior colliculus.  

Responses of direction-selective (DS) ganglion cells (GCs) were recorded extracellularly from their axon terminals in the superficial layer of the tectum opticum (TO) of immobilized goldfish, Carassius auratus gibelio (Bloch).  

It is classically divided into superficial layers predominantly containing visual neurons and deep layers containing multisensory and premotor neurons. Injections into the superficial layers revealed tangential connections within superficial layers and radial superficial-layer to deep-layer connections. Within superficial layers, horizontal connections were found over the entire rostro-caudal axis and were mostly directed laterally, i.e. The present results suggest that intrinsic connections within superficial layers and radial superficial-layers to deep-layers exist in human SC.  

At E12-13, bundles of commissural GFP-positive fibers which appeared to originate outside the SC were distributed at the superficial layer.  

For each coronal (n=6) or parasagittal (n=10) slice, single and multi-unit responses to electrical stimulation of a point in the superficial layers were systematically recorded at different locations along a grid (approximately 300 microm intervals) across the slice. However, regardless of the rostro-caudal or medio-lateral position of the superficial layer stimulation site, the proportion of the deeper layers activated remained remarkably constant, although the volume of activated deep layer tissue was shifted in each case toward the central regions of the SC. This last observation argues against the precise alignment of the superficial and deep layer visual maps, suggesting instead that the arrangement of the superficial layer projection may more closely relate to the organization of deep layer auditory and/or somatosensory representations..  

The dimensions of this wider region (approximately 2 mm diam) corresponded to those of the dendrites of superficial layer wide-field neurons.  

Only in rare instances could a co-localization be observed, for example in the superficial layer of the superior colliculus.  

Depolarization induced by nicotine enhanced the N-methyl-D-aspartate receptor-mediated excitatory postsynaptic potential component and lowered the threshold of bursting response in the SGI neurons to stimulation of the superficial layer.  

Although the direction selective properties of the superficial layer cells of the cat's superior colliculus have been extensively studied, the mechanisms underlying this property remain controversial.  

The superficial layers receive visual inputs and the deeper layers send descending motor command to the brainstem and spinal cord. When the collicular circuit is disinhibited from gamma-amino butyric acid A (GABA(A)) receptor-mediated inhibition, the signal transmission through the interlaminar connection is enormously facilitated and neurons in the deeper layers exhibit bursting response to stimulation of the superficial layer with non-linear amplification mechanism that depends on the activation of NMDA-type glutamate receptors.  

In the UXVPs of rats with monocular enucleation at birth, patterned visual stimuli induced Fos-like immunoreactive (FLI) neurons much more densely in wide areas of the superficial layer throughout the superior colliculus (SC), and in the striate and extrastriate areas of the visual cortex (VC).  

Nor was the stimulation effect due to the activation of superficial layer visual neurons rather than the intermediate layers of the SC because stimulation of the superficial layers produced effects opposite to those found with intermediate layer stimulation.  

Applying a single brief (0.5 ms) pulse of current to the superficial layer of rat collicular slices evoked prolonged bursts of excitatory postsynaptic currents (EPSCs) in the cells of the intermediate layer. To examine the contribution of neurons within the superficial layer to the production of these bursts, we determined how superficial neurons respond to the same current pulses that evoke bursts in the intermediate layer. Recordings from 61 superficial layer cells revealed 19 neurons that produced multiple action potentials following stimulation.  

Together, these results suggest that the neurones in collicular superficial layer contact TRNs and, consequently, support the idea that the superficial layers contribute to collicular outputs producing eye- and head-orienting movements..  

After LY354740 (3.0mg/kg), 4 of the 42 regions measured showed statistically significant changes from vehicle-treated controls: red nuclei (-16%), mammillary body (-25%), anterior thalamus (-29%), and the superficial layer of the superior colliculus (+50%). Significant increases (P < .05) in glucose use were evident in the following: the superficial layer of the superior colliculus (+81%), locus coeruleus (+57%), genu of the corpus callosum (+31%), cochlear nucleus (+26%), inferior colliculus (+20%), and the molecular layer of the hippocampus (+14%).  

We have recently found that GABA(C) receptor subunit transcripts are expressed in the superficial layers of rat superior colliculus (SC). Electrical stimulation of the SC optic layer induced a biphasic, early and late, potential in the adjacent superficial layer.  

Intracellular recording techniques were used to evaluate the effects of norepinephrine (NE) on the membrane properties of superficial layer (stratum griseum superficiale and stratum opticum) superior colliculus (SC) cells. The present in vitro results are consistent with those of the companion in vivo study which suggested that NE-induced response suppression in superficial layer SC neurons was primarily postsynaptic and chiefly mediated by both beta2 and beta1 adrenoceptors..  

Single-unit recording and micropressure ejection techniques were used to test the effects of norepinephrine (NE) on the responses of neurons in the superficial layers (the stratum griseum superficiale and stratum opticum) of the hamster's superior colliculus (SC). Analysis of effects of NE on visually evoked and background activity indicated that application of this amine did not significantly enhance signal-to-noise ratios for most superficial layer SC neurons, and signal-to-noise ratios were in some cases reduced.  

While a monotonic increase in Fos-like immunoreactivity with increasing stimulus level was observed in most nuclei, for cells of the superficial layer of the dorsal cochlear nucleus, a non-monotonic change with increasing stimulus level was seen. This dorsal cochlear nucleus non-monotonicity may indicate that, at higher levels of stimulation, a secondary indirect inhibitory input, probably associated with activation of deep layer dorsal cochlear nucleus cells, reduces excitatory responses at the superficial layer of the dorsal cochlear nucleus.  

Endothelin-1 (ET-1) (10 pmol) microinjected into the superficial layer of superior colliculus induces decreases in blood pressure (control, 108 +/- 5 mmHg, n=6; ET-1, 71 +/- 4 mmHg, n=5).  

TO1 neurons have widefield dendritic trees that arborize in the layers of retinal afferents and form a neuropil in the superficial layer; axons constitute the crossed tectospinal tract. TO5 cells have slender primary dendrites and small-field dendritic trees that extend into the superficial layers of retinal afferents; their fine axons constitute the bulk of the pathways ascending to the ipsilateral and contralateral thalamus.  

Calretinin and calbindin D28K were localized in the superficial layers of rabbit superior colliculus (SC). The results suggest the anti-calretinin immunoreactivity in the superficial layer of rabbit SC contrasts starkly with that of other animals..  

We have examined whether the superficial layers of the superior colliculus (SC) provide the source of visual signals that guide the development of the auditory space map in the deeper layers. Aspiration of the caudal region of the superficial layers of the right SC on postnatal day 0 did not cause a reorganization of this projection. Consequently, recordings made when the animals were mature showed that visual units in the remaining superficial layers in rostral SC had receptive fields that spanned a restricted region of anterior space. Auditory units recorded beneath the remaining superficial layers were tuned to corresponding anterior locations. Both the superficial layer visual map and the deeper layer auditory map were normal in the left, unoperated SC. The majority of auditory units recorded throughout the deeper layers ventral to the superficial layer lesion were also tuned to single sound directions. Equivalent lesions of the superficial layers made in adult ferrets did not alter the topographic order in the auditory representation, suggesting that visual activity in these layers may be involved in aligning the different sensory maps in the developing SC..  

Sink V was observed in the most superficial layer.  

Statistically significant decreases (P < 0.05 and P < 0.02) in glucose utilization ranging from -15 to -26% were also displayed in the superior colliculus superficial layer, auditory cortex, ventroposterior nucleus of the thalamus, molecular layer of the hippocampus, dentate gyrus, medial amygdaloid nucleus, median raphe nucleus, subthalamic nucleus, medial preoptic area of the hypothalamus and anterior hypothalamus.  

Microinjection of endothelin-1 (ET-1; 10 pmol) into the superficial layer of the superior colliculus caused systemic and regional hemodynamic changes, as measured by injection of radioactive microspheres at the peak of the hypotensive effect of endothelin-1.  

In addition, we examined the effects of the endothelin receptor antagonists, (R)-2-[ (R)-2-[ (S)-2-[ [ 1-hexahydro-1H-azepinyl)]carbonyl]amino-4-++ +methylpentanoyl]-amino-3-(2-pyridyl)propionic acid (FR139317) (endothelin ETA receptor-selective), (+)-(1S,2R,3S)-3-(2-carboxymethoxy-4-methoxyphenyl)-1-(3,4-methylenediox yphenyl)-5-(prop-1-yloxy)indane-2-carboxylic acid (SB209670) (endothelin ETA/ETB receptor non-selective) and N-cis-2,6-dimethylpiperidinocarbonyl-L-gamma-metLeu-D-1-m ethoxycarbonylTrp-D-Nle (BQ-788) (endothelin ETB receptor-selective antagonist) on the responses following administration of endothelin-1 into the superficial layer of the superior colliculus.  

Here we have investigated the systemic and regional cardiovascular changes induced by injection of ANGII into the superficial layer of the superior colliculus (SC) of male rats anaesthetised with urethane. Injection of ANGII (0.1, 1 and 100 nmol/rat) into the superficial layer of the SC significantly (P < 0.05) increased, in a dose-dependent manner, the mean arterial blood pressure (MAP) while decreasing the heart rate, (e.g.  

We examined synaptic transmission between these layers in vitro by stimulating the superficial layer while using whole-cell patch-clamp methods to measure the responses of intermediate layer neurons. Stimulation of superficial layer neurons evoked excitatory postsynaptic currents in premotor cells.  

A specific immunolabeling, but at moderate intensity, was also observed in the thalamus, substantia nigra, superficial layer of the superior colliculus, motor trigeminal nucleus and facial nucleus.  

Microinjection of endothelin-1 (1-10-100 pmol) into the superficial layer of the superior colliculus of anaesthetised rats caused dose-dependent decreases in blood pressure.  

Previous studies have reported that superficial layer cells in the superior colliculus (SC) give an enhanced response to a stimulus when it is the target for an eye movement. SC cells in the superficial layers tended to give enhanced responses when the attended test stimulus was inside the receptive field compared to when the (physically identical) distracter was inside the field.  

-38 to -52%, in the superficial layer of superior colliculi, at PN day 20 and PN day 30, respectively) in parallel with a mild increase in both NMDA (e.g.  

Of the 33 neurons in the superficial layer, many neurons were of the non-specific type.  

Although superficial layer neurons responded exclusively to visual stimuli and visual inputs predominated in deeper layers, there was also a rich nonvisual and multisensory representation in the superior colliculus.  

In the present paper, we examined the synaptic relationships between a heterogeneous class of large synaptic terminals called mossy fibers and their targets within subdivisions of the granule cell domain known as the lamina and superficial layer.  

Autoradiography with 125I-neurotensin in normal and enucleated hamsters was used to define the distribution of receptors for this peptide in the superficial layers of the superior colliculus (SC). The effects of neurotensin on individual superficial layer cells were tested in single-unit recording experiments.  

A dense serotonin (5-HT)-containing projection to the superficial layers of the superior colliculus (SC) has been demonstrated in diverse mammalian species, but how 5-HT may affect visual signals within these laminae is largely unknown. In recordings of superficial layer neurons from SC slices, application of 5-HT during blockade of 5-HT1A receptors with spiperone reduced the amplitude of EPSPs evoked by stimulation of the optic tract.  

The regional distribution of the 5-HT1B/1D [ 3H]sumatriptan binding sites was in agreement with previously published studies (striatonigral system, hypothalamus, central gray, superficial layer of the superior colliculus) and corresponded to the pattern of serotonin-5-O-carboxymethyl-glycyl [ 125I]tyrosinamide labeling in consecutive sections.  

Injection of HRP into the unilateral vitreous body demonstrated that the terminal labeling of the optic projections was seen bilaterally in the suprachiasmatic nucleus (SCH), the ventral (GLv) and dorsal (GLd) lateral geniculate nuclei, the intergeniculate leaflet (IGL), the medial pretectal nucleus (NTOM) of the pretectum (PT) and the superficial layer of the superior colliculus (CS), with contralateral predominance, and only contralaterally labeled terminals were found in the lateroposterior thalamic nucleus (LP), the lateral pretectal nucleus (NTOL) of the PT, the dorsal (DTN) and medial (MTN) terminal nuclei of the accessory optic system (AOS). The contralateral CS received retinal fibers in the superficial layer, while ipsilateral optic fibers projected sparsely to the stratum opticum of the colliculi.  

No superficial layer neuron (0/27) responded predictively when a stimulus would not be brought into their receptive fields by a saccade.(ABSTRACT TRUNCATED AT 400 WORDS).  

Small extracellular injections of biocytin in brain slices showed that the optic layer gray matter contains a population of stellate cells that are in position to receive the input from the superficial layer.  

There were relatively high levels of binding in the olfactory system, superficial layer of cortices, the amygdala and the thalamus.  

superficial layer superior colliculus (SC) neurons were recorded extracellularly with multibarreled recording/ejecting micropipettes.  

However, a small number of regions were found to be insensitive to either NBQX or LY-293558, most notably the superior colliculus superficial layer which failed to display significant alterations in glucose use following any concentration of either AMPA antagonist.  

Single-unit recording and iontophoretic techniques were used to test the effects of serotonin (5-HT) on the responses of neurons in the superficial layers (the stratum griseum superficiale and stratum opticum) of the hamster's superior colliculus (SC). The present results demonstrate that 5-HT markedly depresses the visual responses of most superficial layer SC neurons.  

Evidence for relative enrichment of M3 receptors was obtained in the thalamus, the superficial layer of the superior colliculus, the periqueductal region, the substantia nigra pars reticulata and the pons.  

We used localized injections of lidocaine to block action potentials of fibers that passed through the superficial layers and injections of CoCl2 to block synaptic transmission in these layers. Injection of lidocaine into the superficial layers completely abolished the visual- and/or optic chiasm-evoked responses of all 40 deep layer cells tested. Thus, fibers that either pass through or synapse in the superficial layers are necessary for the visual responses of deep layer neurons. Injections of CoCl2 restricted to the superficial layers significantly reduced the visual responsivity of 86% of 92 deep layer neurons tested and abolished the visual responses of 68% of these cells. superficial layer injections of CoCl2 were equally effective in reducing the responses of neurons with dendrites that ascended into the superficial layers (all seven cells tested and recovered) and those of cells with dendrites restricted to the deep layers (six of seven cells tested and recovered). Deep CoCl2 injections abolished the visual responses of three of four cells with dendrites restricted to the deep layers and only one of four cells with dendrites that ascended into the superficial layers. These results indicate that descending interlaminar axons from visually responsive superficial layer cells may be responsible for the visual responsivity of most neurons in the deep SC layers of hamster. Also, some deep layer neurons in this species may receive effective visual input through their dendrites that ascend into the superficial layers, where they are likely to be contacted by retinal axons or axon collaterals of superficial layer cells..  

Visually responsive neurons in the superficial layers of the hamster's superior colliculus (SC) can be divided into distinct morphological and functional classes. In an effort to determine whether this change reflected differential transneuronal degeneration of these cell types or alterations in the dendritic arbors of surviving cells, this study re-examined this issue by restricting the analysis to a specific and relatively homogeneous subpopulation of superficial layer neurons, those that project to the lateral posterior nucleus (LP).  

The physiological recordings confirmed previous results that normally visual superficial layer neurons develop somatosensory receptive fields in the enucleated animals.  

Many cells in the superficial layers of the monkey superior colliculus are sensitive to the relative motion between a small target moving through the classic receptive field and a textured, moving background pattern that fills the visual field beyond the classic receptive field.  

Primary retinorecipient structures (superficial layer of the superior colliculus and the dorsal lateral geniculate nucleus) showed a response to light but not to shock.  

After WGA-HRP injection into the vitreous cavity of one eye, terminal labeling was seen in the suprachiasmatic nucleus, dorsal and ventral lateral geniculate nuclei, pretectum and superficial layer of the superior colliculus.  

Dense or loose clusters of D-type cells were localized in the external edge of the laminar trigeminal nucleus, dorsal motor nucleus of the vagus, external cuneate nucleus, nucleus praepositus hypoglossi, central, pontine, and periaqueductal gray, superficial layer of the superior colliculus, and area medial to the retroflexus.  

These percentages were essentially the same for superficial layer visual cells and somatosensory neurons in the deep laminae.  

The first lesions were observed 18 weeks postinoculation in the most superficial layer of the superior colliculus and in the lateral geniculate body contralateral to the side of the inoculation.  

isthmi projects to the most superficial layer. Fibers from posterior thalamus and tegmentum project to both superficial and deeper layers in the tectum, but not to the most superficial layer. The ipsilaterally projecting isthmotectal fibers terminate in the deeper superficial layers.  

The immunoreactivity was associated with neurons but not glial cells and was generally weak in the neutrophils with the exception of areas such as the triangular septal nucleus, pontine nuclei, superficial layer of the superior colliculus, and gray matter of the spinal cord.  

Recordings from the superficial layer of the superior colliculus displayed negative waves, whereas recording from the deeper layer displayed positive waves.  

Intracellular recording and horseradish peroxidase (HRP) injection techniques were employed to examine the projections of superficial layer [ stratum griseum superficiale (SGS) and stratum opticum (SO)] superior collicular (SC) neurons in the hamster that sent axon collaterals into the deep laminae (those ventral to the SO) of this structure. Sixty-nine neurons were studied, selected from a sample of over 185 HRP-filled superficial layer cells on the basis of having heavily stained axons. Not all cell types in the superficial layers contributed equally to this interlaminar projection: 78.6% (n = 11) of the recovered wide-field vertical cells, 55.0% (n = 11) of the narrow-field vertical cells, 16.7% (n = 2) of the stellate cells, 40.0% (n = 2) of the marginal cells, 18.2% (n = 2) of the horizontal cells, and 28.6% (n = 2) of neurons we could not classify on the basis of their somadendritic morphology projected to the deep layers.  

To accomplish this, an extracellular single unit identified as retinotectal fiber was first isolated from the superficial layer of the optic tectum and intracellular responses were recorded from a tectal neuron in the vicinity of the extracellular recording electrode.  

By contrast the injection of kainic acid into the colliculus leaves the intermediate layer lattice intact while causing a local reduction in the superficial layer. Thus, it is concluded that the lattice in the intermediate layers is mainly dependent on afferents from the laterodorsal tegmental and pedunculopontine nuclei while the sheet in the superficial layers is mainly dependent on intrinsic cells..  

The graft data show that, as in normal superior colliculus, development of high alpha-BTX binding is limited to areas containing presumptive superficial layer cells..  

The most striking differences in beta-adrenergic receptor localization between the mouse and rat brain were in the superficial layer of the superior colliculus and the bed nucleus of stria terminalis. The superficial layer of the mouse superior colliculus had high densities of beta-1 receptors and much lower densities of beta-2 receptors, while the superficial layer of the rat superior colliculus had moderately high densities of beta-2 and lower densities of beta-1 receptors.  

Serotonin uptake sites labeled by 3H-paroxetine were highly concentrated in the dorsal and median raphe nuclei, central gray, superficial layer of the superior colliculus, lateral septal nucleus, paraventricular nucleus of the thalamus, and the islands of Calleja.  

An intermediate labelling was found in the anteromedial and suprarhinal DA terminal fields of the cerebral cortex, the basolateral, medial and lateral amygdaloid nuclei, the endopiriform nucleus, the primary olfactory cortex, the globus pallidus, the superior colliculus (especially the superficial layer), the nucleus amygdaloideus corticalis and the dorsal hippocampus (molecular layer of the CA1 and dentate gyrus).  

Very high densities of binding sites are observed in the cerebellar cortex (molecular layer), the pyriform cortex, the superior colliculus (superficial layer), the supraoptic nucleus and the nucleus of the tractus solitarius.  

In the midbrain of the rat, binding was most notable in the interpeduncular nucleus, the superficial layer of the superior colliculus, the periaqueductal gray, and the paranigral nucleus.  

In the midbrain, binding was high in the superficial layer of the superior colliculus and the medial geniculate while intermediate binding was recorded in the lateral geniculate and the lateral aspect of the central gray.  

A very high density of uptake sites occurs in the nucleus tractus solitarius, in the superficial layer of the superior colliculus, in several thalamic nuclei, and also in geniculate body nuclei.  

High concentrations of nicotinic [ 3H]ACh binding sites were observed in the anterior and medial nuclei of the thalamus, the medial habenula and the superficial layer of the superior colliculus.  

Only a small number of superficial layer neurons contributed axons to the intercollicular pathway.  

The responses of tecto-LP neurons did not differ appreciably from those of superficial layer collicular cells that could not be antidromically activated by LP shocks.  

Projections from auditory cortex form the complement of those from the cochlear nuclei and superior olivary complex, that is, they terminate in a thin band overlying the dorsal cortex and the superficial layer of external cortex.  

This altered sensory organization is consistent with the prior observation that superficial layer collicular cells, whose axons comprise a major input to LP, were responsive to somatosensory stimulation in hamsters which were enucleated at birth..  

Both drugs significantly stimulated LCGU in the superior colliculus (superficial layer) and nucleus of the optic tract, but not in the visual cortex.  

Retrogradely labeled fibers of the optic nerve could not be recognized in this study, although in a previous study the superficial layer of the tectum mesencephali received a few projections from the contralateral eye.  

In the portion of the tectal map representing the zone of binocular vision, 50% of the superficial layer units and 100% of the deep; layer units were driven binocularly.  

A reduction in local glucose utilization occurs in the superficial layer of the superior colliculus of rats following exposure to 0.5% 2,5-hexanedione in drinking water for 3 weeks.  

In normal hamsters relatively localized, visual cortical deposits of radioactive amino acids resulted in superficial layer labeling only in portions of the colliculus which corresponded to the locus of the cortical deposit.  

Areas with receptors having low affinity for the drugs (Type 2 receptors) included the superficial layer of the superior colliculus, the caudate-putamen and parts of the dentate gyrus.  

After crossing, retinal projections distribute to the area preoptica, the thalamus dorsalis pars lateralis, the thalamus ventralis pars lateralis, the corpus geniculatum laterale, the nucleus pretectalis, and the superficial layers of the tectum mesencephali. In elasmobranch fish the optic nerve fibers enter the tectum through the zona interna of the stratum cellulare externum and send their axons into the more superficial tectal layers, while in actinopterygians and amphibians the majority of the optic fibers enter the tectum through the superficial layer and distribute their axons to deeper tectal layers..  

SC cells of the visual layer were classified into 8 types: classes Ia and Ib in the most superficial layer (N3 zone), class II in the thin layer below the N3 (N2 zone) and classes IIIa, IIIb, IVb and IVc in the deepest layer below the N2 (N1 zone).  

Studies of the effect of the dopamine agonist apomorphine on local cerebral glucose utilization by means of the carbon-14-labeled deoxyglucose method demonstrate a dose-dependent metabolic activation in the superficial layer of the superior colliculus in the rat. Apomorphine stimulated glucose utilization in a number of other cerebral structures, but only the effect in the superficial layer of the superior colliculus depended on an intact retinal input.  

When HRP was introduced into the superficial layer of the superior colliculus, labeled neurons were observed in the ipsilateral dorsal and ventral subgroups and in the contralateral middle subgroup.  

The mf are unmyelinated axons which originate at the torus longitudinalis and run lateralwards, parallel to one another, along the tectum's most superficial layer (stratum marginale).  

The spike latency of neurons in the deep grey and white layers of anterior colliculus elicited by stimulation of the optic chiasm (OC), lateral geniculate body (LGB) and visual cortex (VC) was longer than that of neurons in the more superficial layers: optic and intermediate grey layers. These results strongly suggest that noradrenaline originating in the LC could produce an inhibition of neuronal activities in the deep grey and white layers, and such is probably the result of inhibition of neurons located in the superficial layer of the anterior colliculus..  

Efferent projections were only seen in the most superficial layer of the ipsilateral optic tectum (stratum fibrosum marginale).  

The spatial distribution of the source of "OFF" responses was circumscribed to the ventral part of the superficial layer of the superior colliculus.  

Cells in the superficial layers of monkey superior colliculus respond more vigorously to a spot of light falling in their receptive fields when the monkey uses that spot of light as the target for a saccadic eye movement. The enhancement response is not present in the upper quarter-millimeter of the superficial layers, suggesting that the effect is not present in retinal afferents which terminate primarily in this area of the superficial layers. The hypothesis advanced in the preceding paper that eye movement-related activity from intermediate and deep colliculus layers is directed upward to converge with visually related activity in the superficial layers is extended to include an input from cells in these deeper layers (or their afferents) to the superficial layer cells....  

A vigorous discharge of these cells before an eye movement was dependent on the presence of a visual target; the cells seemed to combine the visual input of superficial layer cells and the movement-related input of the intermediate layer cells. The size of the movement fields of these cells were about the same size as the visual fields of superficial layer cells just above them....  

The fine structure of the superficial layer of the optic tectum of the pigeon, Columba livia, has been examined both in normal animals and after unilateral eye removal.  

Less than one-quarter of superficial layer cells showed directional selectivity to a moving object, the majority of these favoring up and nasal movement.  

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