Injections of retrograde tracers in Pd labeled non-gamma-aminobutyric acid (GABA)-ergic wide-field vertical cells located in the lower stratum griseum superficiale and Stratum Opticum of the medial SC, whereas injections in Pc labeled similar cells in more lateral regions. 
A major stream of transplanted cells migrated through the Stratum Opticum and penetrated for up to about 0.5mm into the optic nerve head.
Immunoreactivity for GH is also traced through the optic nerve head, at the back of the eye, into the optic nerve, through the optic chiasm, into the optic tract and into the Stratum Opticum and the retinorecipient layer of the optic tectum, where the RGC axons synapse.
Regenerating optic nerve axons projected into the Stratum Opticum-stratum fibrosum et griseum superficiale by week 2, the stratum griseum centrale by week 4, and stratum album centrale by week 6.
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..
Experiments focused on narrow-field vertical neurons, a documented excitatory cell type in the stratum griseum superficiale using bipolar stimulation in the Stratum Opticum.
While the dorsal one primarily involved the Stratum Opticum and the stratum griseum intermediale, the ventral one innervated the deep strata, although some fibers did connect these tiers.
One of them had an apical dendrite ramifying at the boundary between the Stratum Opticum (SO) and the SFGS, and the other had dendritic branches restricted to the stratum album centrale or stratum periventriculare.
We compared the ultrastructure and synaptic targets of terminals of cortical or retinal origin in the stratum griseum superficiale and Stratum Opticum of the rat superior colliculus.
Our results reveal that OPCs dispersed bilaterally along the optic tract and then migrated to the optic tectum in the Stratum Opticum (SO).
We classified the majority of these neurons as small (perimeters of 40-50 microm), and localized diffusely throughout the superficial grey and Stratum Opticum.
By 19 weeks, GAP-43 immunoreactivity was present in the Stratum Opticum as well as the deeper fibres layers, indicating the development of fibre pathways following those laminae.
In the Stratum Opticum (SO), only 10.5% of the NGFI-A(+) cells were also CB(+).
In the optic tectum (OT) of trout, as in amniotes, RELN immunoreactivity increases within specific cell layers as lamination proceeds, and decreases when it is complete, except in the Stratum Opticum (SO), where RELN-ir cells are observed throughout life.
Our previous studies have shown that when slices of the rat superior colliculus (SC) are exposed to a solution containing 10 microM bicuculline and a low concentration of Mg2+ (0.1 mM), most neurons in the intermediate gray layer (stratum griseum intermediale; SGI), wide-field vertical (WFV) cells in the optic layer (Stratum Opticum; SO), and a minor population of neurons in the superficial gray layer (stratum griseum superficiale; SGS) exhibit spontaneous depolarization and burst firing, which are synchronous among adjacent neurons.
Wide-field vertical neurons in the Stratum Opticum have features intermediate between neurons in the SGS and SGI.
The Stratum Opticum did not show any changes in volume with age. The number of glial cells in the stratum griseum superficiale showed an increase between the 3rd and 26th month, while the Stratum Opticum suffered no change..
Injections into the stratum marginale (SM) labeled neurons in the Stratum Opticum and stratum fibrosum et griseum superficiale (SFGS).
Developing chick retinotectal projections extend rostrally in the superficial Stratum Opticum of the tectum until they reach their appropriate target zone. In this study, we show that the polysialylated neural cell adhesion molecule is expressed both on the membrane of these developing projections and in the Stratum Opticum and retinorecipient layers during the period of optic innervation. The removal of polysialic acid caused several distinct abnormalities, including random dorsal/ventral meandering of fibers in the Stratum Opticum, a distorted branching and extension of arbors in the retinorecipient layers, and inappropriate synaptic vesicle accumulation in pretarget areas.
While the astrocytes were mainly found in the Stratum Opticum (SO), stratum album centrale (SAC) and stratum fibrosum periventriculare (SFP), with their processes extending throughout the entire optic tectum region, the oligodendrocytes were mainly scattered in the SO, stratum griseum centrale (SGC) and SAC.
The postsynaptic responses to afferent stimulation first propagated in the Stratum Opticum and stratum fibrosum et griseum superficiale in an anterograde fashion in the afferents and then expanded vertically into the deep layers.
The optic tectum was extremely small, and the thickness of the Stratum Opticum and stratum fibrosum et griseum superficiale was reduced.
The optic tectum, especially the Stratum Opticum and the stratum griseum et fibrosum superficiale were hypoplastic and contained reduced numbers of optic nerve fibers.
We used whole-cell patch-clamp recording to measure the responses of these projection neurons to electrical stimulation of their afferents in the Stratum Opticum (SO) before and during local pressure injections of ACh.
Frontally cut sections showed that innervations provided by the three main nigral zones form a mosaic of complementary domains stratified from the Stratum Opticum to the ventral part of the intermediate collicular layers, with the somatic afferents sandwiched between the visual and the auditory ones.
Some of them ran lateromedially close to the SGS-Stratum Opticum (-SO) limit, giving rise to many collaterals which invaded the lower part of the SGS; whereas others formed narrow terminal arbors, mostly branching in the SO.
In these layers a higher density of boutons was observed in the stratum zonale (SZ) and lower stratum griseum superficiale (SGSl) than in the upper stratum griseum superficiale (SGS(u)) and Stratum Opticum (SO).
Cells expressing moderate to high levels of somatostatin messenger RNA formed a dense band in the lower third of stratum griseum superficiale/upper Stratum Opticum; two less distinct tiers of labelling were seen in deeper layers. Cells expressing moderate to low levels of proenkephalin messenger RNA were located in lower stratum griseum superficiale/upper Stratum Opticum and intermediate laminae. Expression of neuropeptide Y messenger RNA was relatively low and mostly confined to cells in stratum griseum superficiale and Stratum Opticum.
We analyzed the distribution and the morphological characteristics of neurons expressing AMPA-type glutamate receptor subunits (GluR1 and GluR2) in the superficial partition (stratum zonale (SZ), stratum griseum superficiale (SGS) and Stratum Opticum (SO)) of the rat superior colliculus.
In normal tench RT97 is a good marker for the horizontal cells in the retina, for growing ganglion cell axons which run along the optic nerve from the retina to the optic tectum and of the axon terminals in the Stratum Opticum and stratum fibrosum and griseum superficiale in the optic tectum.
The widefield vertical neurons of the lower stratum griseum superficiale (SGS3) and upper Stratum Opticum (SO) of the superior colliculus provide an extrageniculate route for visual information to reach the pulvinar.
On the other hand, the densest concentration of PV labeled cells and terminals is found within a single dense tier that spanned the ventral part of the startum griseum superficiale (SGS) and the dorsal part of the Stratum Opticum (SO).
Our results show that the number of NADPH-d stained cells was small and virtually identical in Stratum Opticum (SO) and stratum griseum superficiale (SGS) and their staining was very light, particularly in SGS.
These neurons had two short basal dendrites branching in the cell layer and a long apical dendrite extending to the stratum fibrosum et griseum superficiale and Stratum Opticum.
Dense projections of the NR to the Stratum Opticum and stratum fibrosum et griseum superficiale of the optic tectum are demonstrated.
The Stratum Opticum is the main terminal area of the optic nerve, and contains stellate and horizontal neurons.
A second ligand is observed in the endfeet region of radial processes in the developing Stratum Opticum, the site of initial retinal axon invasion.
These cells were recorded throughout the stratum griseum superficiale and Stratum Opticum and constituted 50% of our sample. These cells constituted almost 26% of our sample and were located in the lower stratum griseum superficiale, Stratum Opticum and the upper part of the stratum griseum intermediale. These low-velocity-excitatory/high-velocity-suppressive cells were recorded from the stratum griseum superficiale, Stratum Opticum and stratum griseum intermediale and constituted about 17% of the sample.
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.
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).
Unlike cortical axons in normal mice in early postnatal ages, those in anophthalmic mice formed a disperse bundle in the Stratum Opticum.
Injections of Miniruby into the suprageniculate nucleus labelled predominantly neurons in the Stratum Opticum of the superior colliculus, whereas injections into the medial division of the medial geniculate body, the posterior intralaminar nucleus and the peripeduncular nucleus labelled predominantly neurons in the deep layers of the superior colliculus.
Application of parvalbumin and calbindin immunohistochemistry and nicotinamide adenine dinucleotide phosphate-diaphorase histochemistry reveals the following lamination pattern: The Stratum Opticum, stratum griseum centrale and stratum album centrale remain unstained, while the laminae of the stratum griseum et fibrosum superficiale exhibit a roughly complementary staining pattern of calbindin (laminae c, d, e, f, g, i) and parvalbumin (laminae a, h, i). The Golgi material reveals the following cell types in the stratum griseum et fibrosum superficiale: marginal cells in the Stratum Opticum and in lamina h and i, horizontal cells in laminae a and c, large and small radial cells in laminae b, d, h and i, multiform cells in lamina b, bitufted cells in lamina d and e, large pear-shaped cells in lamina g, wide-field cells in lamina j, and stellate cells in lamina j and in the stratum griseum centrale.
Normal tectal sections showed dark staining of a subclass of type XIV neuron with somas at the top of the periventricular layer and an apical dendrite ascending to Stratum Opticum. At 5 weeks postcrush, PKC staining could also be seen in the medial and lateral optic tracts and Stratum Opticum at the front half of the tectum and very lightly over the terminal zones.
The patches that normally develop in the rostral part of the Stratum Opticum were not present, and uncrossed axons were distributed densely in this layer and in the lower portion of the stratum griseum superficiale throughout the rostrocaudal and mediolateral extents of the SC.
With the appearance of the tenth layer named Stratum Opticum at 8.0 cm CRL the laminar pattern corresponds to the characteristics of adult animals..
In tectum, ephrin-B1 transcripts are expressed in a high dorsal to low ventral gradient in the neuroepithelium and the protein is present along the processes of radial glia and is concentrated at their endfeet in the Stratum Opticum, at the time retinal axons are growing through it.
The superior colliculus contained fiber degeneration localized principally to two superficial layers (i) the Stratum Opticum (layer III) and (ii) stratum cinereum (layer II).
The projection to the ipsilateral SC underwent refinement by P50, becoming restricted to its rostral pole, and presented as discrete patches within the Stratum Opticum.
We found that eye removal clearly induced 5-HT7 receptor mRNA expression in the Stratum Opticum of superior colliculus, this effect being especially evident at postnatal day 21 (P21).
From postnatal day 0 to day 2, retinal fiber fascicles in the stratum griseum superficiale/Stratum Opticum were darkly stained for synaptic vesicle protein 2.
Quantitative analysis revealed that 90.8 +/- 2.2% (mean +/- standard deviation) of the calbindin-immunoreactive neurons in the stratum griseum superficiale (SGS) projected to the dorsal lateral geniculate nucleus (LGNd) and that 91.3 +/- 4.3% of calbindin-immunoreactive neurons in the Stratum Opticum (SO) projected to the lateral posterior nucleus (LP).
The present study combined immunocytochemistry and quantitative morphometry to determine the effects of eye removal in fetal life, at birth, or in adulthood upon the expression of calbindin and parvalbumin by neurons in the retinorecipient laminae (the stratum griseum superficiale (SGS) and Stratum Opticum (SO)) of the rat's superior colliculus (SC).
Stimulation was delivered with a bipolar electrode positioned in Stratum Opticum in thin slices and in the contralateral optic nerve in thick slices.
The noxious deep somatic and noxious visceral manipulations also evoked, compared to halothane-only animals, reductions in the numbers of Fos-like IR cells in the Stratum Opticum of the superior colliculus and the unlaminated portion of the external subnucleus of the inferior colliculus.
Following optic nerve crush, we observed a more extensive labeling of the microglia in the crushed optic nerve and in the contralateral optic tectum affecting the Stratum Opticum and stratum fibrosum et griseum superficiale.
In addition, primitive inner plexiform layer processes in the retina, tectobulbar axons, and non-retinal fibres of the tectal Stratum Opticum, contain large amounts of CRYP alpha.
The primary visual area 17 projected only to the superficial laminae, i.e., stratum zonale (SZ), stratum griseum superficiale (SGS), and Stratum Opticum (SO).
Cek8 is expressed throughout the pathway of the retinal ganglion cell axons, including the nerve fiber layer of the retina, optic nerve, optic chiasm, and Stratum Opticum of the tectum.
The lower band was less dense (29% of the cells) and located in the lower third of SGS and in the upper layers of the Stratum Opticum.
The superficial layers (stratum zonale, stratum griseum superficiale (SGS) and Stratum Opticum) are intimately associated with the processing of visual information.
The contralateral CS received retinal fibers in the superficial layer, while ipsilateral optic fibers projected sparsely to the Stratum Opticum of the colliculi.
At the light microscopic level, labelling was faintly to moderately intense in most perikarya of the stratum zonale, stratum griseum superficiale and Stratum Opticum. Furthermore, strong glutamate-immunoreactive terminal-like elements were accumulated most densely in stratum zonale, stratum griseum superficiale and Stratum Opticum. Ipsilateral superior colliculus to cortical ablation exhibited subtle changes characterized by a moderate increase in perikaryal immunostaining in stratum zonale, stratum griseum superficiale and Stratum Opticum and by an apparent discrete reduction of labelled dots in stratum griseum superficiale and Stratum Opticum. In cases with combined lesions, strongly immunoreactive cell bodies and dendrites were accompanied by a massive disappearance of labelled terminal-like elements in stratum zonale, stratum griseum superficiale and Stratum Opticum.
In the chick, retinal ganglion cell axons enter the optic tectum through a superficial lamina (the Stratum Opticum), extended branches into deeper laminae, and arborize in specific "retinorecipient" laminae, where they form synapses. Among many spatiotemporal pattern of expression documented, three were particularly noteworthy: (1) The cell adhesion molecules NgCAM/L1 and TAG-1/axonin-1 were concentrated in the Stratum Opticum. Thus, molecules in these three categories could provide signals to retinal axons that promote extension through the Stratum Opticum, induce arborization or synaptogenesis in retinorecipient laminae, and prevent sprouting into adjoining laminae.
At early stages, tenascin is predominantly accumulated in the Stratum Opticum, the zone of ingrowing retinal ganglion cell axons, and along their prospective pathway. In the Stratum Opticum, the molecule is associated with radial glial fibres, glial endfeet and retinal ganglion cell axons located in the immediate neighbourhood of radial glial fibres. Together, these observations suggest that tenascin in the developing and prospective Stratum Opticum might serve as a performed pathway to support growth of retinal ganglion cell axons in the tectum..
A weak immunoreactivity is found in the rostral stratum marginale (SM), strong labelling of the neuropil is shown in a thin band in Stratum Opticum (SO), two bands in stratum fibrosum et griseum superficiale (SFGS) and two bands in stratum griseum centrale (SGC).
Chronic stress significantly reduced the number of binding sites (Bmax) in the anterior lobe of the pituitary, the dentate gyrus, the CA1-CA3 areas of the hippocampus, and in both the stratum griseum superficiale and the Stratum Opticum of the superior colliculus.
griseus tectalis), two strata of the optic tectum (Stratum Opticum and s.
Every LM sector receives abundant projections from the polymodal sylvian anterior cortical area, the reticular thalamic nucleus, and the Stratum Opticum and intermediate layer of the superior colliculus.
AngII did not modify the signal when injected in collicular layers ventral to the Stratum Opticum.
Responses in the Stratum Opticum and stratum griseum intermediale were more severely affected by cortical lesions than those in the stratum griseum superficiale.
The distribution study displayed that these conditions were responsible for a heterogeneous binding pattern as shown by elevated receptor levels being located in visual brain centers, such as the Stratum Opticum, nucleus pretectalis, and nucleus geniculatus lateralis, pars ventralis, while lower values were found in the nucleus lateralis hypothalami and nucleus isthmi pars magnocellularis.
To test between these two hypotheses surgical knife wounds were made either parallel (in the sagittal plane) or perpendicular (in the transverse plane) to the course of axons in the Stratum Opticum, embryonic neocortical tissue was transplanted at the coordinates of these tectal slits, and retinal afferent ingrowth visualized 1-90 days after surgery using anterogradely transported HRP.
Most of them are located in the Stratum Opticum and in the stratum griseum superficiale. Our results indicate that ILNs represent a minority of neurones in the superficial layers but may constitute a substantial population of neurones in the Stratum Opticum connecting the visual and the multimodal collicular layers..
The results from the intact cats confirmed previous reports that areas 17 and 18 project most heavily to stratum zonale (SZ) and stratum griseum superficiale (SGS) and LS cortex projects most heavily to Stratum Opticum (SO) of the superior colliculus.
Tenascin, however, was abundant in the Stratum Opticum of the tectum, the target of retinal axons in the brain.
In Stratum Opticum, neuronal activity was similar in all three groups of cats.
In the adult, labeled axons and boutons are most dense in the Stratum Opticum and stratum griseum intermedium.
The tectal neurons have a long perpendicular dendrite, which branches out in the Stratum Opticum (SO).
In normal adult hamsters, fibers from the ipsilateral eye form dense clusters in the lowermost stratum griseum superficiale (SGS) and Stratum Opticum (SO).
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 projection from the rat's superior colliculus (SC) to the lateral posterior nucleus of the thalamus (LP) has previously been described as arising from a morphologically homogeneous population of neurons in the Stratum Opticum (SO).
The results demonstrated that a prominent pathway originates in the superficial gray layer and terminates in Stratum Opticum. In comparison, the projection from the superficial gray layer to the layers beneath Stratum Opticum is extremely sparse. The pathway from the superficial gray layer to Stratum Opticum has a columnar distribution, extending about 100 microns rostrally and caudally from the center of the injection site. The results suggest that Stratum Opticum may serve as a link between the superficial gray layer and the deeper layers..
The upper laminae of the recipient's SC (approximately up to Stratum Opticum) were removed by aspiration after the neocortex overlying the SC was aspirated out.
Little tenascin was present in the retinal optic fiber layer, and the optic nerve and tract, but was abundant in the Stratum Opticum of the tectum, the target of retinal axons in the brain.
corticalis), three layers of the optic tectum (Stratum Opticum pars externa, stratum fibrosum et griseum superficiale, stratum album centrale), and a single target in the tegmentum (n.
Our findings reveal that seventeen of the 25 cortical areas project upon some portion of the superficial layers (stratum zonale, stratum griseum superficiale, and Stratum Opticum, SO).
Calbindin-D-28k showed a laminar distribution of neurons with a predominance in deep portions of superficial grey matter and in ventral portions of Stratum Opticum.
Animals with functional transplants expressed cFos throughout the depth of the stratum griseum superficiale and Stratum Opticum of the superior colliculus, thus apparently activating an additional population of superior collicular cells.
The highest activity occurs in the stratum zonale and stratum griseum superficiale, contrasting with the pale neuropil in the Stratum Opticum, where only a few positive neurons are found.
The three brains injected in the MT area resulted in SC labels that involved the superficial gray layer (SGS), the Stratum Opticum (SO) and the intermediate gray layer (SGI), sparing the layers below SGI.
The fibers of this aberrant decussation are confined mainly to the superficial gray layer, with little ingrowth or termination in the deeper Stratum Opticum; laterally, most termination is in the superficial part of the superficial gray. We found that in the presence of IN-1, but not a control antibody, recrossing retinofugal fibers, observed at postnatal day 12, traverse the Stratum Opticum as well as the superficial gray, with greater depth of termination in superficial gray and Stratum Opticum.
The highest density of immunoreactive fibres was found in the area ventralis telencephali, the mesencephalic tegmentum, the Stratum Opticum of the optic tectum, the central gray of the brainstem, the caudal part of the fasciculi solitarii and the dorsal horn of the spinal cord.
High numbers of beta 2-LI somata were found only in the nucleus spiriformis lateralis, whereas neuropil staining for beta 2-LI was intense in the nucleus geniculatus lateralis ventralis, nucleus suprachiasmaticus, nucleus lateralis anterior, nucleus habenularis lateralis, area pretectalis, griseum tecti, nucleus lentiformis mesencephalis, nucleus externus, and nucleus interpeduncularis, and in the stratum griseum centrale, stratum griseum et fibrosum superficiale, and Stratum Opticum of the tectum.
The results reveal contralateral retinal projections to fifteen sites: two in the hypothalamus (the nuclei suprachiasmaticus and periventricularis), five in the thalamus (the nuclei ovalis, geniculatus lateralis ventralis, geniculatus laleralis dorsalis, dorsolateralis anterior and ventrolateralis), five in the pretectal region (the nuclei geniculatus pretectalis, opticus pretectalis ventrolateralis, lentiformis mesencephali, posterodorsalis and griseus tectalis), two in the optic tectum (the Stratum Opticum and the stratum fibrosum et griseum superficiale), and one in the tegmentum (the nucleus opticus tegmenti).
In the stage 34 (day 8) chick embryo, phosphotyrosine-modified proteins were abundant within outgrowing neuronal processes in the optic nerve head and nerve fiber layer of the retina, and in the developing Stratum Opticum at the surface of the optic tectum.
After an intravitreal injection of horseradish peroxidase, most labelled axon terminals were found in the stratum griseum superficiale and Stratum Opticum of the contralateral superior colliculus. However, a small proportion (approximately 2%) of retinal ganglion cell axon terminals were located in deeper layers of the superior colliculus between the Stratum Opticum and the periaqueductal grey matter. Terminals were smaller in the upper two-thirds of the stratum griseum superficiale than in the lower one-third of this layer, the Stratum Opticum, and the stratum griseum intermedium.
We suggest that the lower one-half of the superficial grey layer and the Stratum Opticum together constitute a subdivision of the superior colliculus that is specialized to detect strong discontinuities in relative motion.
Despite this spatial proximity, axons from the two pathways do not intermix, but instead restrict their growth to defined areas, thus forming two separate plexiform layers, the Stratum Opticum and the stratum album centrale.
Correlations among a variety of neural structures suggested the importance of stratum marginale (SM), Stratum Opticum (SO), and stratum fibrosum et griseum superficiale (SFGS), stratum griseum centrale (SGC) and stratum periventriculare (SPV) in vision, of stratum album centrale (SAC) and SGC for olfaction, and of SPV for the processing of acoustico-lateral information..
Posterior cortical axons arrive in the SC on postnatal (P-) day one (the first 24 hours after birth = P-0) and begin to arborize in the superficial laminae (the stratum griseum superficiale [ SGS] and Stratum Opticum [ SO]) within one day after they enter the tectum.
However, labelled fibers also extended into the superficial laminae (the stratum griseum superficiale and Stratum Opticum) reaching as far as the SC surface.
Thus Nissl staining and degeneration experiments were done resulting in differences in the Stratum Opticum (SO) of the CS between microphthalmic and control mice.
Few labeled cells were found in the Stratum Opticum, and the stratum zonale (SZ) showed no labeled cells.
ADA-like immunoreactive structures were seen only as postsynaptic elements to different kinds of nonimmunoreactive terminals and were mostly localized in the ventral third of the SGS and the dorsalmost Stratum Opticum (SO).
In bilaterally enucleated rats and on the contralateral side of monocular-enucleated rats, many small strongly immunoreactive MEAGL-containing neurons, projecting processes horizontally or obliquely toward the surface, appeared in the deepest part of the SGS and the superficial part of the Stratum Opticum (SO), in contrast to the disappearance of the fusiform-shaped weakly stained neurons in the SGS.
No immunostained somata appear in the Stratum Opticum. The most striking effect of unilateral enucleation was the dramatic appearance of a laminarly distributed population of L-ENK-I and/or ENK-8-I neurons in the dorsal Stratum Opticum of the SC contralateral to the enucleated side.
Methionine- and leucine-enkephalin immunoreactive fibers were found in discrete sublayers in the following strata: Stratum Opticum, stratum fibrosum et griseum superficiale, stratum griseum centrale, stratum, and album centrale.
Immunoreactive fibers were present in all laminae of the superior colliculus, but they were most dense in the lower part of the stratum griseum superficiale, the Stratum Opticum, the stratum griseum profundum, and the stratum album profundum.
They had elongated arbors with an average cross-sectional area of 78,045 microns2 (SD = 14,252) and innervated the SGS, the Stratum Opticum (SO), and upper stratum griseum intermediale (SGI).
Area 17 projected most heavily to the dorsal Stratum Opticum (SO) and lower half of stratum griseum superficiale (SGS) with lighter label extending up to the collicular surface.
In colchicine-treated rats, the most remarkable changes occurred in SP-I neurons following eye enucleation at birth; large numbers of SP-I neurons appeared in the ventral part of the stratum griseum superficiale (SGS), Stratum Opticum (SO) and stratum griseum intermediale (SGI) of the deafferentated SC.
For this study, we examined the optic (Stratum Opticum, SO), intermediate gray (stratum griseum intermedium, SGI), intermediate white (stratum album intermedium, SAI), and deep gray (stratum griseum profundum, SGP) layers.
The density of DBH-positive fibers was very low in the Stratum Opticum (SO) and increased in density in the stratum griseum intermediale (SGI) and the other deep layers.
During deep pentobarbital anesthesia: (1) Vigorous small-field (2-5 degrees) multi-unit responses were recorded from microelectrodes in the lower stratum griseum superficiale (SGS) and upper Stratum Opticum (SO), evoked by the motion of a 40 degrees black edge.
In the ipsilateral SC, most of the labeled neurons were distributed in the upper part of the Stratum Opticum (SO) and the lower part of the stratum griseum superficiale (SGS).
Centrally, Glu+ was observed in axons in the optic nerve and tract, and in Stratum Opticum and stratum fibrosum et griseum superficialis (SFGS) of the tectum.
SP-like immunoreactivity constituted four tectal laminae, two of them occurring in the Stratum Opticum. LENK-like immunoreactivity formed three laminae, one in the Stratum Opticum. BOMB-like immunoreactivity formed one lamina within the Stratum Opticum and one in the tectal efferent layers. Layers 1 and 2 of the Stratum Opticum revealed high AChE-activity, whereas low activity was found in deep fiber layers containing tectal efferents.
This focus straddles the stratum griseum superficiale/Stratum Opticum (SGS/SO) border.
The label was tangentially and radially exuberant involving the prospective Stratum Opticum, the adjacent part of the stratum griseum superficiale and also the strata intermediale.
Deposits of PHA-L in the stratum griseum superficiale (SGS) resulted in labelled terminal swellings in the Stratum Opticum and all of the deep laminae (the stratum griseum intermediate [ SGI], stratum albumin intermedium [ SAI], stratum griseum profundum [ SGP], and stratum albumin profundum [ SAP]).
In the mesencephalon, labelled fibers were found in the nucleus intercollicularis and in all layers of the optic tectum except the Stratum Opticum.
Adenosine deaminase immunoreactive cells were found in the Stratum Opticum and lower stratum griseum superficiale; substance P immunoreactive cells were localized to the upper stratum griseum superficiale, and calcitonin gene-related peptide immunolabelled neurons were situated in deeper strata.
The labeled cells in the superior colliculus were located within the deep part of stratum griseum superficiale and the superficial part of Stratum Opticum, and were composed of multipolar cells, vertical fusiform cells and horizontal cells.
Presence of a projection containing adenosine deaminase (ADA)-like immunoreactivity from the Stratum Opticum (SO) to the dorsomedial portion of the lateral posterior nucleus of the thalamus (LPN) of the rat was demonstrated using a method combining retrograde tracing by horseradish peroxidase (HRP) and immunohistochemistry for ADA.
It was obvious from fluorescent images obtained from anterogradely filled axons that these axons deserted the superficial Stratum Opticum (SO) to penetrate the stratum griseum et fibrosum superficiale (SGFS) by making right-angled turns within the SO.
We have employed intracellular injection of horseradish peroxidase (HRP) and 3-dimensional, computer-assisted reconstruction to delineate the organization of the dendrites of horizontal cells in the superficial laminae (the stratum griseum superficiale-SGS, and Stratum Opticum-SO) of the hamster's superior colliculus.
After intraocular injection of WGA-HRP, anterograde labels were observed in the stratum griseum superficiale and Stratum Opticum of the superior colliculus contralateral to the injection site.
Cells in the most lateral portion of the SNr project to a horizontal, patchy tier in the interface region between the Stratum Opticum and the stratum griseum intermediate (SGI).
Other medium-to-small optic terminals were found in Stratum Opticum a and b (60a,b), SFGSb, SFGSc, and stratum griseum centrale c (SGCc).
The exit sequence of the regenerated axons from the Stratum Opticum into the tectal neuropil was normal: temporal first, nasal last.
These dendrites crossed the Stratum Opticum, and their fine ramifications reached the stratum zonale.
We have found that Thy-1 is associated with retinal axons from the time of their arrival at the tectum and that its expression reflects the elaboration of the Stratum Opticum.
Light microscopy of semithin epoxy sections indicated that degenerative changes, consisting largely of swollen axons and myelin debris, appeared first in the upper Stratum Opticum (SO) and lower SGS on D1,2, progressed upward throughout the middle SGS by D4, and finally involved the entire SGS and lower stratum zonale (SZ) by D5-7.
Long-Evans, male rats were implanted with indwelling stimulating electrodes in the optic chiasm and recording electrodes in the Stratum Opticum of the superior colliculus.
Their cell bodies were recovered mostly (4/5) in the Stratum Opticum of the SC.
Their cell bodies are situated mainly in the stratum griseum intermedium and occasionally in the Stratum Opticum. T neurons are located mainly in the ventral Stratum Opticum and the dorsal stratum griseum intermedium.
A third pathway originates principally from cells in the Stratum Opticum and terminates in an area just below the cholinesterase-rich region of the LP, designated as the ventral division of the LP.
The somas of the recovered tecto-LP cells were located, with two exceptions, in, or near, the borders of the Stratum Opticum (SO).
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.
vagus, central acustic area, Crista cerebellaris, Bulbus olfactorius, Eminentia granularis, Stratum Opticum (of the optic tectum), Torus longitudinalis, Nucleus habenularis, Valvula cerebelli, Corpus cerebelli, Telencephalon, Tectum opticum, Diencephalon, Torus semicircularis, mesencephalic tegmentum.
All axons in the superficial fascicle layer Stratum Opticum (SO) and some in the synaptic layer stratum fibrosum et griseum superficiale (SFGS) were unbranched and tipped with a leading growth cone.
In the optic lobes the superficial layers of stratum griseum and fibrosum showed a strong selective labelling of alpha 1, alpha 2 and beta binding sites and the strong selective labelling of alpha 2 binding sites extended to the layer of Stratum Opticum.
After injections in the LGd, LGv, Pb and PT, labeled neurons were present throughout the stratum griseum superficiale and the upper portion of the Stratum Opticum.
Retinofugal fibers are labeled in the Stratum Opticum (SO), stratum fibrosum et griseum superficiale (SFGS), stratum griseum centrale (SGC), stratum album centrale (SAC) and stratum periventriculare (SPV).
These results indicate that the superior colliculus of Pteronotus is composed almost entirely of the layers beneath Stratum Opticum.
The 2-deoxy-D-[ 14C]glucose autoradiographic technique was used to assess metabolic activity across stratum griseum superficiale, Stratum Opticum, and stratum griseum mediale of the superior colliculus, at intervals of 1 to 90 days after a unilateral visual cortex lesion.
Neurons of the Stratum Opticum only responded to visual stimuli, such as modulations of the light level or the motion of an object.
At this stage retinal axons leave the Stratum Opticum (SO) and invade the stratum griseum et fibrosum superficiale (SGFS), where arborization takes place.
In the superficial layers of the superior colliculus the levels of choline acetyltransferase and acetylcholinesterase are highest in the stratum zonale and lowest in the Stratum Opticum; in the intermediate gray layer of the superior colliculus acetylcholinesterase- and choline acetyltransferase-stained fibres are distributed into dense patches.
In many cases, they ascended out of the deep laminae into the Stratum Opticum (SO) and/or stratum griseum superficiale (SGS).
Two of the recovered neurons were located in the stratum griseum superficiale (SGS), three were in the Stratum Opticum (SO), ten were in the stratum griseum intermediale (SGI), 11 were in the stratum album intermedium (SAI), 11 were in the stratum griseum profundum (SGP) and two were located in the stratum album profundum (SAP).
Concurrently, the fiber bundles in the deep SS, identified as the Stratum Opticum (SO), give rise to individual, nonfasciculated fibers, which arborize within SGS.
Six layers are readily distinguished: a fairly thick stratum marginale, a narrow Stratum Opticum and stratum fibrosum et griseum superficiale, a well-developed stratum griseum centrale, a stratum album centrale and a compact stratum periventriculare. In regard to comparative aspects of tectal organization, it became apparent that although most neuronal types are similar to those reported in other teleostean fish, there are certain obvious differences such as: pyramidal cell somata not confined to stratum fibrosum et griseum superficiale, but also clustered in the adjacent Stratum Opticum, presenting stratified or diffuse basilar dendritic arbors; and a change from vertical to oblique and almost horizontal neuronal orientation in the ventral and caudal tectum. A cell of stratum griseum centrale with an ascending axon to Stratum Opticum.
A second intensely labeled region was found in Stratum Opticum and stratum griseum intermediate of the superior colliculus.
On the day of birth the axons course through both stratum griseum superficiale (SGS) and Stratum Opticum (SO); during the following 4 days the axon trunks disappear from SGS and are subsequently found only in SO.
The main trunk of the apical dendrites also gave off several branches in the stratum fibrosum et griseum superficiale (SFGS) and reached the Stratum Opticum (SO).
Their parent axons course caudally in the Stratum Opticum within fascicles of 200-300 fibers of varying diameters.
The parent axon ascends vertically and just below the Stratum Opticum turns rostrad to follow the optic fibers to the diencephalon.
In contrast to the classical lamination pattern of the superior colliculus, the flank has no overlying layer II (stratum griseum superficiale, SGS) or layer III (Stratum Opticum, SO)..
The Stratum Opticum of the mutant rat appeared as a narrow band with few fiber components, but it contained some medium-sized polygonal neurons.
Intracellular recording, receptive field mapping, and horseradish peroxidase (HRP) injection techniques were used to determine the structural and functional characteristics of neurons in the superficial laminae (stratum griseum superficiale and Stratum Opticum) of the hamster's superior colliculus (SC).
The other, 7G4, also binds to Müller cells, However, in the tectum it binds to a small cell type in the Stratum Opticum.
During the time that connections would begin to shift in the tectum a second population of axons appears at the bottom of Stratum Opticum, some with characteristics of growth cones.
The majority of T neurons are located in the ventral Stratum Opticum or dorsal stratum griseum intermediale; X3 and X5 neurons are situated immediately below in the dorsal stratum griseum intermediale, while X1, X2, X4, and I neurons are indiscriminately distributed within the deeper layers.
Current source-density analysis revealed that the two slower conducting fibre populations synapse in the upper third of the stratum griseum superficiale on dendrites whose cell bodies appear to be found in the lower part of this layer and in the Stratum Opticum. The two faster conducting populations synapse deeper, near the border of the stratum griseum superficiale and Stratum Opticum, on neurons with cell bodies that may lie towards the upper part of the stratum griseum superficiale.
Retinotectal optic axons were found in a superficial lamina just above the Stratum Opticum, in the Stratum Opticum, in three layers of the stratum fibrosum et griseum superficiale, in a lamina just beneath the stratum fibrosum et griseum superficiale, and in the stratum album centrale just above the stratum periventriculare.
A small population of mainly medium-sized and large ganglion cells project to the deep stratum griseum superficiale and to the Stratum Opticum. The ipsilateral projection is restricted to the deep stratum griseum superficiale and Stratum Opticum and consists predominantly of medium-sized and large ganglion cells..
In normal animals, retinal fibers withdrew from the superficial layers of the superior colliculus, and the projection became concentrated in the Stratum Opticum, where denser clumps of label in the rostral part of the superior colliculus were first seen at day 5.
Neurones that responded to both visual and auditory stimuli presented separately and gave enhanced or depressed responses to bimodal stimulation were found throughout the deep layers, but were concentrated in the stratum griseum intermediale and extended into the Stratum Opticum..
From the earliest stages of optic fiber ingrowth, the fibers from the two eyes are completely intermixed in the Stratum Opticum (SO).
In the tectum immunofluorescence was characteristically distributed in two rows of horizontally aligned patches, most evidently reflecting the orderly array of myelinated fiber bundles in the Stratum Opticum and stratum album.
The first myelinated fibres in the SC appear at 15 days but the Stratum Opticum is still not recognizable.
Of 34 cells recovered from the deep laminae (those ventral to the Stratum Opticum--SO), 26 were exclusively somatosensory and 10 of these extended dendrites into the superficial layers, the stratum griseum superficiale (SGS) and SO.
Most binocular cells are distributed in the Stratum griseum superficiale (SGS) and the Stratum Opticum (SO).
Optic tectum, Stratum Opticum: fine, medium; stratum fibrosum et griseum superficiale: fine, medium, coarse, segregated in sublayers; stratum album centrale: fine, medium, coarse.
Type L1 axons were thicker than type U axons and terminated in deeper regions of the SGS and in the Stratum Opticum (SO).
A small number of labeled fibers also reached the Stratum Opticum (SO) and lower stratum griseum superficiale (SGS)..
However, following tracer deposits in the superior colliculus that are confined to the layers below the Stratum Opticum (deep layers), more neurons are labeled along the lateral bank than along the medial bank of the middle suprasylvian sulcus. Conversely, tracer deposits in the superior colliculus dorsal to and including the Stratum Opticum label more cells in the medial than the lateral bank. Axon labeling in the superior colliculus is generally densest in the Stratum Opticum and extends either dorsally into the superficial layers or ventrally into the intermediate gray layer.
As predicted, the axons had three parts: (1) fascicular segment (in the Stratum Opticum), (2) extrafascicular segment (in the synaptic neuropil), and (3) terminal arbor (also in the neuropil).
Over 95% of the labeled cells were located in the lower one-half of the stratum griseum superficiale (SGS) and the upper Stratum Opticum (SO).
Unlike projections from striate cortex, those from MT are not limited to the upper layer of the stratum griseum superficiale but rather extend ventrally from the upper through the lower layer of the stratum griseum superficiale and even include the Stratum Opticum.
Labeled boutons were found in stratum zonale (SZ) and in stratum griseum superficiale (SGS), but not in Stratum Opticum (S0).
In tectum, the regenerated optic fibers reestablished fascicles in Stratum Opticum, but they were less orderly than in the normals.
Tecto-LGNd neurons with small spindle form were located in the stratum griseum superficiale of the superior colliculus (SC), whereas tecto-LP neurons with polygonal shape were found in the Stratum Opticum of the SC..
Approximately 80% of the labeled cells occurred in the Stratum Opticum and 20% in the stratum griseum superficiale.
After injections placed dorsal to the Stratum Opticum in the superior colliculus, the parabigeminal nucleus is the only mesencephalic and/or rhombencephalic structure in which labeled neurons are observed.
Collicular cells producing a decline were encountered mostly in the ventral part of the stratum griseum superficiale, and the Stratum Opticum, whereas collicular cells that were related to an increased geniculate response were more frequently found dorsally.
Fibers which arise from the central temporal retina occupy deeper layers, whereas fibers from the peripheral temporal retina occupy more superficial layers in the optic tract and in the Stratum Opticum on the anterior tectum. The growth cones of early retinal fibers growing directly on the tectal surface show a different morphology to later growth cones growing on top of the Stratum Opticum on the tectum..
The auditory cells were located throughout the deeper laminae and also in the lower part of the Stratum Opticum.
Labeled boutons were found in the stratum zonale (SZ) and in the stratum griseum superficiale (SGS), not in Stratum Opticum (SO).
The spatiotemporal pattern of visual inputs to the stratum griseum superficiale (SGS) and Stratum Opticum (SO) of the cat superior colliculus (SC) has been determined by an analysis of the current sinks occurring during postsynaptic activity following stimulation of each optic nerve (ON) and the optic chiasm (OX).
Responses to photic stimulation were recorded from the visual wulst, the Stratum Opticum and the nucleus rotundus.
By a somewhat novel application of the HRP in which the enzyme is deposited intravitreally in two or three sequential installments at 24 h intervals and by modifications that increase the sensitivity of the tetramethylbenzidine reaction procedure, we have successfully mapped the distribution of a significant number of retinal ganglion cell axons below the Stratum Opticum in the intermediate gray layer of the superior colliculus.
In two species, contralaterally, visual inputs project to nuclei geniculatus dorsalis and ventralis, pretectum and colliculus anterior (at the level of Stratum Opticum and the stratum griseum superficiale).
The regenerated axons within the optic nerve are still unmyelinated at the moment of visual recovery, whereas some fibers within the Stratum Opticum pars profunda of the corresponding optic tectum are already myelinated.
In normals, the ipsilateral retinocollicular projection consisted almost entirely of a series of patches along the stratum griseum superficiale-Stratum Opticum border in the rostral one-third of the colliculus.
In the adult, ipsilateral retinotectal input was restricted to a narrow, dense, patchy, mediolateral band in Stratum Opticum in the rostral colliculus. In the newborn, the ipsilateral retinotectal input was less dense, free of patches, spread in thickness to include much of the Stratum Opticum and the superficial grey, and spread in extent to include all but the caudal pole of the colliculus.
Degeneration methods revealed projections in the tectum to the Stratum Opticum, stratum griseum et fibrosum superficiale, and stratum album centrale.
Retinal axons continue caudally from the Stratum Opticum of the contralateral superior colliculus at the medial and lateral sides of the superior colliculus.
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