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1.
Contralateral corticofugal projections from the lateral,suprasylvian and ectosylvian gyri in the cat
Dr. N. Berman B. R. Payne 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1982,47(2):234-238
Summary Contralateral corticofugal projections were investigated following multiple injections of a mixture of tritiated leucine and proline into the lateral, postlateral, suprasylvian and ectosylvian gyri of adult cats. Transported label was found in several Contralateral subcortical regions. These included the claustrum, caudate-putamen, thalamic intralaminar nuclei, pretectum, and the superior and inferior colliculi. These results show that the crossed corticofugal projections are common in the cat and are more extensive than has been previously reported.Abbreviations AC
Anterior Commissure
- AM
Anteromedial Nucleus
- AV
Anteroventral Nucleus
- Cd
Caudate
- CeM
Central Medial Nucleus
- CL
Central Lateral Nucleus
- Cl
Claustrum
- CM
Centromedian Nucleus
- GP
Globus Pallidus
- IC
Inferior Colliculus
- LD
Laterodorsal Nucleus
- LGd
Dorsal Nucleus of the Lateral Geniculate complex
- LP
Lateral Posterior Nucleus
- MD
Mediodorsal Nucleus
- MG
Principal Nucleus of the Medial Geniculate complex
- OT
Optic Tract
- Pa
Anterior Pretectal Nucleus
- Pl
Pulvinar Nucleus
- Put
Putamen
- Re
Reuniens Nucleus
- RN
Red Nucleus
- SC
Superior Colliculus
- SN
Substantia Nigra
- TRC
Tegmental Reticular Nucleus, central division
- VA
Ventral Anterior Nucleus of thalamus
- VB
Ventrobasal Complex of thalamus
- 3
Oculomotor Nucleus 相似文献
2.
K. Kawamura M.D. T. Konno 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1979,35(1):161-175
Summary The retrograde labeling of cortical neurons with horseradish peroxidase (HRP) was used to investigate the morphological features of neurons in various cortical areas projecting to the superior colliculus in the cat.Corticotectal cells were found to be labeled in layer V of the entire cerebral cortex. The number of labeled cells and their locations varied according to the sites of injections of HRP in the colliculus. Most of the Corticotectal cells identified in the present study were small (9–20 m in diameter, 66%) and medium (20–40 urn, 30%) pyramidal neurons and only 4% of them were large (more than 40 m). The labeled cells, 261 in total number, had somal diameters of 20.8±8.0 m (mean and SD). The range of sizes of the labeled neurons was different in different cortical areas. For example, the labeled neurons in the Clare-Bishop area had a greater proportion of large diameter cells than in other areas.The present findings are largely in agreement with the previous data of anterograde degeneration methods with respect to the topographical correlation of the Corticotectal projections. However, in some cortical areas, e.g., the sensorimotor and the first visual (area 17) cortex of the lateral surface of the hemisphere, relatively small numbers of Corticotectal neurons appear to have been labeled by retrogradely transported HRP. The sparsity of the labeled neurons in certain cortical areas may reflect the existence of Corticotectal neurons with axon collaterals supplying brain structures other than the superior colliculus.Abbreviations A.c.
Aqueductus cerebri
- AEct
Gyrus ectosylvius anterior
- AEs
Sulcus ectosylvius anterior
- AI
Stratum album intermediale
- AL
Gyrus lateralis anterior
- AP
Stratum album profundum
- AS
Gyrus sylvius anterior
- Cd
Nucleus caudatus
- F.l.m.
Fasciculus longitudinalis medialis
- GI
Stratum griseum intermediale
- GP
Stratum griseum profundum
- GS
Stratum griseum superficiale
- Ic
Inferior colliculus
- L
Left
- MEct
Gyrus ectosylvius medius
- MS
Gyrus sylvius medius
- MSup
Gyrus suprasylvius medius
- N.r.
Nucleus ruber
- O
Stratum opticum
- P
Pontine nuclei
- P.c.
Pedunculus cerebri
- PEct
Gyrus ectosylvius posterior
- P.g.
Periaqueductal gray matter
- PSigm
Gyrus sigmoideus posterior
- PSup
Gyrus suprasylvius posterior
- R
Right
- Sc
Superior colliculus
- S.n.
Substantia nigra
- Z
Statum zonale
- II
Optic nerve
- III and IV
Motor nuclei of cranial nerves 相似文献
3.
P. P. Battaglini MD S. Squatrito C. Galletti M. G. Maioli E. Riva Sanseverino 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1982,47(1):28-32
Summary Direct projections from visual areas 17, 18, 19, and lateral suprasylvian visual area (LS) to the striatum were searched for in 12 adult cats using the autoradiographic technique to detect neuronal pathways. Striatal labels were found only after injections in areas 19 and LS. Projections homolateral to the injection sites were observed from both areas to the head and body of the caudate nucleus and to the putamen. Contralateral projections were found from both areas 19 and LS: however, area 19 did not project to the contralateral putamen. The extent of contralateral projections was smaller and they were confined within the same regions as the homolateral ones. Silver grains were often arranged in cluster-like patches, which were more evident ipsilaterally, in the head of the caudate nucleus and after injections in area LS.The present data support the view of a not strictly topographical segregation of striatal projections from the cat visual cortex.Supported by a grant from the CNR, Rome, Italy 相似文献
4.
Satoda T Matsumoto H Zhou L Rose PK Richmond FJ 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2002,144(3):397-413
Mesencephalic neurons projecting to the upper cervical spinal cord were examined by mapping the distributions of labeled cells after injecting fluorescent tracers or wheat-germ agglutinin conjugated to horseradish peroxidase (WGA-HRP) into the C1 segment. Injections into the central or deep regions of the ventral horn produced retrograde labeling in cells of several mesencephalic regions. The majority of cells were found contralaterally in the superior colliculus and red nucleus, and ipsilaterally in and around the interstitial nucleus of Cajal (INC), in the cuneiform region, and in the fields of Forel. Smaller numbers of cells were located in the periaqueductal gray matter, nucleus annularis, and magnocellular nucleus of the posterior commissure. Dorsomedial injections in the ventral horn near the ventral commissure labeled only a subset of these projections, including cells in the mesencephalic reticular formation adjacent to the INC and in the nucleus annularis. Dorsolateral injections labeled some cells in the superior colliculus and were particularly effective at labeling cells in the red nucleus. These results suggest that at least ten different cell groups project to the ventral horn of the first cervical segment. Most, but not all, groups originate from regions implicated previously in the control of eye or head movements. 相似文献
5.
Dr. J. A. Saint-Cyr J. Courville 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1982,45(3):333-348
Summary Descending projections from the mesencephalon and superior colliculus to the inferior olive were analyzed by an autoradiographic tracing method. Injections of tritium-labelled leucine were placed in regions which had previously been identified as sources of afferents to the olive. These were located adjacent to the central gray and extended from the rostral red nucleus to the posterior thalamus. Additional injections were made in the superior colliculus. Other injections were placed in the basal ganglia and thalamus. Injections restricted to one side of the central mesencephalon resulted in predominantly ipsilateral labelling of the olive. After injections in the caudo-medial parafascicular and subparafascicular nuclei and rostral nucleus of Darkschewitsch, deposits of grains were observed in the rostral pole of the medial accessory olive and adjacent ventral lamella of the principal olive. The medial accessory olive contained grains into its middle third. More caudal injections which involved the interstitial nucleus of Cajal as well as the nucleus of Darkschewitsch and rostral red nucleus resulted in the dense labelling of the entire principal olive (except the dorsal cap), the entire medial acessory olive (except subnucleus and the caudo-medial pole) and the caudo-dorsal accessory olive. Injections centered in the caudal magnocellular red nucleus and extending into the rostral parvocellular division labelled the dorsal lamella of the principal olive almost exclusively. When only the caudal part of the red nucleus was involved in the injection, the olive was entirely clear of grains. Minor contralateral distributions were observed in the dorsomedial cell column, the medial tip of the dorsal lamella and in the caudal medial accessory olive. The deep layers of the superior colliculus were found to project strongly to the contralateral medial accessory olive immediately beside subnucleus and weakly to the same area ipsilaterally.Four pathways were identified as contributing fibers to the olivary projections. These were the medial longitudinal fasciculus, the medial tegmental tract, the central tegmental tract and tectospinal or tectobulbar fibers. The rubrospinal tract did not contribute projections to the olive. Injections in the caudate nucleus, entopeduncular nucleus and ventral anterior and ventral lateral thalamic nuclei, did not result in any labeling in the olive.List of Abbreviations AC
anterior commissure
- Cd
caudate nucleus
- CG
central gray
- CP
cerebral peduncle
- CTT
central tegmental tract
- DAO
dorsal accessory olive
- dc
dorsal cap of Kooy
- dmcc
dorsomedial cell column of the inferior olive
- dlPO
dorsal lamella of the principal olive
- Entop
entopeduncular nucleus
- EW
nucleus of Edinger-Westphal
- FR
fasciculus retroflexus
- Fx
fornix
- GP
globus pallidus
- H
H field of Forel
- HRP
horseradish peroxidase
- IC
inferior colliculus
- INC
interstitial nucleus of Cajal
- Int Cap
internal capsule
- IPN
interpeduncular nucleus
- LRN
lateral reticular nucleus
- MAO
medial accessory olive
- MB
mammillary body
- MGB
medial geniculate body
- MLF
medial longitudinal fasciculus
- MRF
mesencephalic reticular formation
- MTT
medial tegmental tract
- ND
nucleus of Darkschewitsch
- NFF
nucleus of the fields of Forel
- NPC
nucleus of posterior commissure
- NPP
posterior pretectal nucleus
- NRTP
nucleus reticularis tegmenti pontis
- n III
third cranial nerve fibers
- OT
optic tract
- PC
posterior commissure
- PF
parafascicular nucleus
- PG
pontine gray
- PO
principal olive
- PTM
medial pretectal nucleus
- RNp
parvocellular red nucleus
- RN
red nucleus
- RST
rubrospinal tract
-
subnucleus beta of the inferior olive
- sPf
subparafascicular nucleus
- SC
superior colliculus
- TH
thalamus
- vlPO
ventral lamella of the principal olive
- vlo
ventral lateral outgrowth of the principal olive
- VTA
ventral tegmental area of Tsai
- ZI
zona incerta
- III
nucleus of third cranial nerve
- XII
nucleus of twelfth cranial nerve
Supported by a grant from the Canadian Medical Research Council to the Group in Neurological Sciences at the Université de MontréalSupported by a postdoctoral fellowship of the Centre de Recherche en Sciences Neurologiques of the Université de Montréal 相似文献
6.
H. H. Elverland 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1978,32(1):117-134
Summary The ascending and intrinsic projections of the superior olivary complex (SO) in the cat were investigated by injection of 3H-leucine and horseradish peroxidase (HRP) in SO and the inferior colliculus (IC), respectively. A topically arranged projection was demonstrated from the nucleus of the trapezoid body (NTB) to the ipsilateral lateral superior olivary nucleus (LSO) with a lesser connection in the opposite direction. The medial superior olivary nucleus (MSO) has a strictly ipsilateral projection, whilst LSO projects symmetrically through the lateral lemniscus (LL) of both sides, to end with topically arranged terminals in the ventrolateral part of the central nucleus of the inferior colliculus (CNIC). Terminal labelling found in the ventral and dorsal nuclei of LL (VNLL and DNLL) probably represents collaterals from bypassing fibres originating in MSO and LSO, respectively. These results were demonstrated by both techniques, whilst in addition the HRP method revealed an ipsilateral and a contralateral projection to IC from VNLL and DNLL, respectively. 相似文献
7.
Lock TM Baizer JS Bender DB 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2003,151(4):455-470
We compared the cortical inputs to the superficial and deep compartments of the superior colliculus, asking if the corticotectal system, like the colliculus itself, consists of two functional divisions: visual and visuomotor. We made injections of retrograde tracer extending into both superficial and deep layers in three colliculi: the injection site involved mainly the upper quadrant representation in one case, the lower quadrant representation in a second case, and both quadrants in a third. In a fourth colliculus, the tracer injection was restricted to the lower quadrant representation of the superficial layers. After injections involving both superficial and deep layers, labeled cells were seen over V1, many prestriate visual areas, and in prefrontal and posterior parietal cortex. Both the density of labeled cells and the degree of visuotopic order as inferred from the distribution of labeled cells in cortex varied among areas. In visual areas comprising the lower levels of the cortical hierarchy, visuotopy was preserved, whereas in "higher" areas the distribution of labeled cells did not strongly reflect the visuotopic location of the injection. Despite the widespread distribution of labeled cells, there were several areas with few or no labeled cells: MSTd, 7a, VIP, MIP, and TE. In the case with an injection restricted to superficial layers, labeled cells were seen only in V1 and in striate-recipient areas V2, V3, and MT. The results are consistent with the idea that the corticotectal system consists of two largely nonoverlapping components: a visual component consisting of striate cortex and striate-recipient areas, which projects only to the superficial layers, and a visuomotor component consisting of many other prestriate visual areas as well as frontal and parietal visuomotor areas, which projects to the deep compartment of the colliculus. 相似文献
8.
Dr. T. Tsumoto K. Suda 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1981,43(3-4):451-454
Summary In 16 cats monocularly deprived from 2 to 3 weeks of age, we studied 53 striate cortical cells which were identified as projecting to the dorsal lateral geniculate nucleus (LGN) on the basis of antidromic activation from LGN and of histological localization within cortical layer VI. As in the normal cat, these cortico-geniculate cells could be classified as slow, intermediate or fast, according to their axonal conduction velocities. The sampling ratio of the slow cells (mostly unresponsive to visual stimuli) was much higher than normal. On the other hand, the ratio of the intermediate (one half were simple cells) and fast cells (all except one were complex cells) was significantly lower than the norm. Also, the average axonal conduction velocities of the complex and simple cells were significantly slower than normal. These results suggest that normal maturation of cortico-geniculate cells, particularly fast and intermediate ones, is retarded or arrested by monocular visual deprivation.Supported by a grant from the Ministry of Education of Japan 相似文献
9.
J. M. Flandrin M. Jeannerod 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1981,42(1):73-80
Summary 1. Unilateral lesions of the superior colliculus were made in normal cats. Following the operation, animals exhibited a typical neglect for contralateral visual space and forced circling toward the ipsilateral side. Optokinetic nystagmus was decreased for a stimulus moving toward the ipsilateral side, particularly in the temporal-to-nasal direction when the eye contralateral to the lesion was stimulated alone. — 2. When tested in the dark, animals exhibited a strong imbalance of their vestibulo-ocular responses (VOR) to velocity steps or to sinusoidal oscillations. Rotation of the animal toward the ipsilateral side produced a VOR with a higher gain, and a shorter phase-lead than in pre-operative controls. VOR was decreased in the opposite direction to a smaller extent, however. The overall asymmetry between the two sides at the post-operative stage was about 40%. — 3. In two animals, spontaneous nystagmus was present in the dark with the fast phase toward the ipsilateral side. — 4. Visual suppression of VOR was abolished during ipsiversive rotation and was still present during contraversive rotation. — 5. The effects of unilateral colliculectomy on VOR were transient. Spontaneous nystagmus disappeared in 3 days. VOR asymmetry in the dark was no longer present after 2–3 weeks. Loss of visual VOR suppression persisted for a few more days. — 6. Superior colliculus exerts a tonic control on static and dynamic components of VOR. This control may mediate part of VOR visual modulation and provide a substitutive input for compensation of pathological VOR asymmetry. 相似文献
10.
B. R. Payne Ph.D. N. Berman 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1984,53(2):462-466
Summary Contralateral corticofugal projections from visual cortical areas to thalamic nuclei were demonstrated in the cat using anterograde transport of tritiated proline. Thalamic nuclei receiving projections from contralateral visual cortex include both subdivisions of the lateral-posterior nucleus, the posterior nucleus of Rioch, and the posterior nuclear complex.Abbreviations
BIC
brachium of the inferior colliculus
-
BN
nucleus of the brachium of the inferior colliculus
-
BSC
brachium of the superior colliculus
-
C
dorsal lateral geniculate nucleus, C laminae
-
CG
central gray matter
-
D
nucleus of Darkschewitz
-
FR
fasciculus retroflexus
-
FTC
central tegmental field
-
H
habenula
-
IPN
interpeduncular nucleus
-
LGNd
dorsal lateral geniculate nucleus, A laminae
-
LGNv
ventral lateral geniculate nucleus
-
LP
lateral posterior complex
-
LPi
interjacent division of lateral posterior complex
-
LPl
lateral division of lateral posterior complex
-
LPm
medial division of lateral posterior complex
- M
mammillary body
-
MGM
magnocellular division of medial geniculate nucleus
-
MGN
medial geniculate nucleus
-
MGP
parvocellular division of medial geniculate nucleus
-
MIN
medial interlaminar division of lateral geniculate nucleus
-
MML
medial medullary lamina
-
NOT
nucleus of the optic tract
-
OT
optic tract
-
P
cerebral peduncle
-
PA
anterior pretectal nucleus
-
PC
nucleus of the posterior commissure
-
PM
medial pretectal nucleus
-
PO
posterior nuclear group
-
PoC
posterior commissure
-
POi
intermediate division of posterior nuclear complex
-
POL
pretectal olivary nucleus
-
POm
medial division of posterior nuclear complex
-
PPT
posterior pretectal nucleus
-
PUL
pulvinar
-
RN
red nucleus
-
RNR
posterior nucleus of Rioch
-
SG
suprageniculate nucleus
-
SGI
stratum griseum intermedium of superior colliculus
-
SGP
stratum griseum profundum of superior colliculus
-
SCSl
lower division of stratum griseum superficiale of superior colliculus
-
SGSu
upper division of stratum griseum superficiale of superior colliculus
-
SN
substantia nigra
-
SO
stratum opticum of superior colliculus
-
TC
tectal commissure
-
III
III nerve
-
IIIN
nucleus of III nerve 相似文献
11.
H. Kennedy C. Baleydier 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1977,28(1-2):133-139
Summary Thalamic projections to the visual cortex were investigated using the Horseradish peroxidase tracing technique. Besides confirmation of a distinct origin of thalamic projections to striate and extra-striate visual cortex, afferents of the intralaminar nuclei (ILN) to visual cortex were demonstrated. These projections of ILN were shown to be specific in that they terminate in areas 18, 19 and Clare Bishop but not area 17. The coupling of these intralaminar projections on to the extra-striate visual system is considered with respect to orientation of gaze. 相似文献
12.
K. Elisevich A. W. Hrycyshyn B. A. Flumerfelt 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1985,58(2):368-378
Summary Injections of combined lectin-conjugated and unconjugated horseradish peroxidase were made in the dorsal (d) and ventral (v) divisions of the paramedian reticular nucleus (PRN), a precerebellar relay nucleus, of the cat. The origins of supramedullary afferent projections to the PRN were identified in the pons, midbrain and cerebral cortex using the transverse plane of section. The data indicate a segregation of input from a number of sites to the dPRN and vPRN. The interstitial nucleus of Cajal projects bilaterally to the dPRN and predominantly to the ipsilateral side. The vPRN receives only a unilateral projection from the ipsilateral nucleus of Cajal. Major afferent projections to the vPRN arise from the ipsilateral nucleus of Darkschewitsch and the intermediate layer of the contralateral superior colliculus. Neither of these sites projected to the dPRN. The raphe nuclei and medial reticular formation of the pons and midbrain contribute a moderate input to both divisions of the PRN. A moderate bilateral cerebral cortical projection arises from the first somatomotor area (SMI). The ventral coronal and anterior sigmoid gyri project mainly to the dPRN and vPRN respectively. Smaller afferent projections arise from the posterior sigmoid gyri and area 6 of Hassler and Mühs-Clement (1964) in the medial wall of the anterior sigmoid gyrus. Inputs from the accessory oculomotor nuclei, tectal regions and the first somatomotor cortex suggest a role in postural control for the PRN which may underlie its involvement in mediating orthostatic reflexes.Abbreviations 3N
oculomotor nerve
- 5ME
mesencephalic nucleus (trigeminal)
- 5MN
motor nucleus (trigeminal)
- 5PN
sensory nucleus, parvocellular division (trigeminal)
- 5SM
sensory nucleus, magnocellular division (trigeminal)
- 12M
hypoglossal nucleus
- 12N
hypoglossal nerve
- AQ
aqueduct
- BC
brachium conjunctivum
- BP
brachium pontis
- CAE
nucleus caeruleus
- Cl
inferior central nucleus (raphe)
- CM
centromedian nucleus
- CNF
cuneiform nucleus
- CS
superior central nucleus (raphe)
- D
nucleus of Darkschewitsch
- DRM
dorsal nucleus of the raphe (median division)
- EW
Edinger-Westphal nucleus
- FTC
central tegmental field
- FTG
gigantocellular tegmental field
- FTP
paralemniscal tegmental field
- ICA
interstitial nucleus of Cajal
- ICC
inferior colliculus (central nucleus)
- INC
nucleus incertus
- INT
nucleus intercalatus
- ION
inferior olivary nucleus
- LLV
ventral nucleus of lateral lemniscus
- LP
lateral posterior complex of thalamus
- MGN
medial geniculate nucleus
- MLF
medial longitudinal fasciculus
- TN
nucleus of optic tract
- P
pyramidal tract
- PCN
nucleus of posterior commissure
- PF
parafascicular nucleus
- PH
nucleus praepositus hypogloss
- PRN
paramedian reticular nucleus (a — accessory division; d — dorsal division; v — ventral division)
- PUL
pulvinar
- SCD
superior colliculus (deep layer)
- SNC
substantia nigra (compact division)
- SON
superior olivary nucleus
- RM
red nucleus (magnocellular)
- RR
retrorubral nucleus
- TB
trapezoid body
- TDP
dorsal tegmental nucleus (pericentral division)
- TRC
tegmental reticular nucleus (central division)
- TV
ventral tegmental nucleus
- V3
third ventricle
- V4
fourth ventricle
- VB
ventrobasal complex of thalamus
- VIN
inferior vestibular nucleus
- VSN
superior vestibular nucleus
- ZI
zona incerta
Supported by the Medical Research Council of Canada 相似文献
13.
D. Guitton M. Crommelinck Dr. A. Roucoux 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1980,39(1):63-73
Summary Electrical stimulation of the cat superior colliculus (SC), in conjunction with the accurate measurement of elicited eye movements and histologically verified electrode positions, has revealed a striking antero-posterior variation in collicular organization. Three zones could be defined in the SC on the basis of eye movement patterns and associated neck muscle EMG activity evoked from the deeper layers. The Anterior zone was coextensive with the central 25 ° of the visual retinotopically coded map contained in the superficial layers. Saccades evoked from this zone were also retinotopically coded, and the latency of EMG activity depended on the position of the eye in the orbit. A similar observation applies to the entire monkey SC. The Intermediate zone was coextensive with the 25 °–70 ° of visual projections. Saccades evoked from this region were goal-directed and were associated with invariant, short latency EMG responses. The Posterior zone was found in the extreme caudo-lateral portion of the SC. Eye movements evoked from this zone were centering saccades associated with constant latency EMG activity. The present results in conjunction with previously demonstrated antero-posterior variations in projections to the SC, suggest that the motor strategies controlling gaze shifts toward visual targets vary depending on the location of the target in the visual field. 相似文献
14.
C. K. Peck 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1986,61(2):447-450
Summary Single unit activity was studied in the intermediate and deep layers of the superior colliculus in two trained cats. Eye movements were recorded with a magnetic search coil, the head being fixed. Discharge rates which varied as a function of eye position were consistently observed in 7 of 67 (about 10%) of the sample of eye movement-related units. These units showed similar changes in firing rate as a function of eye position in total darkness and during task related fixation of visual targets and thus appear to convey an eye position signal. Their activity may originate either from proprioception or from corollary discharge. 相似文献
15.
The amygdaloid complex receives information from all sensory systems, especially from vision. In the primate, the amygdala is reciprocally interconnected with some regions of high-order visual cortices such as TE and TEO and only projects to the primary visual cortex (V1, area 17) without direct projection from V1. However, in the cat little is known about the projection from the amygdala to the primary visual cortex. In this study, anatomical study is carried out in cats to determine whether the amygdala sends feedback projection to area 17. FlouroGold, a fluorescent dye was microinjected into area 17 in cats. In the basal nucleus in the amygdala, the retrograde labeled cells (about 30% of total number of the region of interest observed) are distributed widely in an irregular manner, neither in lamina nor in group. The results provide the first anatomical evidence of the amygdale projection to area 17 in the cat, which is a widely used animal model for vision research. 相似文献
16.
Rushmore RJ Payne BR 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2003,151(4):542-547
We examined the functional impact of a long-standing, unilateral primary visual cortex lesion on the superior colliculus (SC) using radiolabeled 2-deoxyglucose (2DG) as a marker of neural activity. In accord with known corticotectal connectivity and functional influence, 2DG uptake in the superficial layers of the ipsilesional SC was decreased. We also found a decrease in the superficial layers of the contralesional SC. These data suggest that modifications in activity in one SC can have a substantial influence on activity in its contralateral partner, and that processing in one visual hemifield does not occur independently of processing of signals in the opposite hemifield. The effects are not mediated by the contralateral hemisphere but are probably mediated by intercollicular circuitry. 相似文献
17.
D. M. Berson J. Lu J. J. Stein 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1990,79(3):459-466
Summary Most of the retinal input to the cat's superior colliculus (SC) arises from W-cells of the contralateral eye and terminates just below the tectal surface. The goal of this study was to determine whether the strength of this input is uniform over the collicular map or, instead, exhibits topographic variations as has been reported for the retinotectal Y-cell projection (McIlwain and Lufkin 1976). Monosynaptic inputs from the principal W-cell projection mediate the late negative potential (LNP), a collicular field potential that can be evoked by shocks to the optic pathway. We assumed that the amplitude of the potential provided a measure of the strength of the W-cell input to the upper superficial gray layer. Using a fixed stimulus, we measured the maximal amplitude of the LNP at 90 topographically identified tectal sites in 5 cats. The amplitude of the LNP varied as much as 5-fold over the SC and was systematically related to the azimuthal position of the recording site. LNP amplitudes were consistently smallest in the representation of the area centralis and vertical meridian and largest in the representations of the contralateral hemifield periphery and the ipsilateral hemifield. There was little systematic variation in LNP amplitude as a function of elevation in the map. The observed variations did not result from non-uniform activation of retinal afferents or drift in properties of the recording electrodes, stimuli, or preparation. The results suggest that the principal W-cell input to the SC is weaker in the representation of the area centralis than elsewhere in the map. These topographic variations are similar to those reported for the retinotectal Y-cell projection (McIlwain and Lufkin 1976) and are consistent with anatomical evidence for thinning of retinal input in the area-centralis representation (Graybiel 1975; Harting and Guillery 1976; Mize 1983). An important implication of these results is that the scaling of the collicular retinotopic map may not be proportional to the spatial density of tectally projecting W-cells. 相似文献
18.
R. Cortimiglia G. Crescimanno M. T. Salerno G. Amato 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1991,84(3):471-477
Summary The effect of claustrum (CL) stimulation on the spontaneous unitary activity of ipsi and contralateral frontal oculomotor neurons, was studied in chloralose-anaesthetized cats. A total of 205 units was bilaterally recorded in the medial oculomotor area, homologous of the primate frontal eye fields 127 neurons were identified as projecting to the superior colliculus; for 33 of these last units stimulation of the ipsilateral CL provoked an excitatory effect lasting 10–25 ms and appearing with a latency of 5–15 ms; on 8 units the excitatory effect was followed by an inhibition lasting 100–250 ms. Ninety-eight of the 127 neurons were also tested through activation of the contralateral CL: 13 cells showed an excitatory effect lasting 10–35 ms and appearing with a latency of 20–50 ms. In three of the thirteen units the excitatory effect was followed by an inhibition lasting 100–150 ms. Complete section of the corpus callosum abolished the contralateral CL effect, suggesting the existence of a direct claustro-contralateral oculomotor cortex pathway running through the corpus callosum. The results could support the hypothesis that the CL may play a role in the bilateral control of the visuomotor performance. 相似文献
19.
H. J. Luhmann L. Martínez Millán W. Singer 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1986,63(2):443-448
Summary Intracortical injections of horseradish peroxidase conjugated with wheat-germ agglutinin (WGA-HRP) reveal a characteristic patchy staining pattern within the superficial layers of cat striate cortex. The patches consist of a dense accumulation of labeled neurons and axonal arborizations. We have investigated the tangential organization and the development of these intrinsic cortical connections by using a flat-mount preparation of area 17. The diameter of the patches varied from 200 to 400 m, the center-to-center distance ranged from 400 to 800 m, and the spread of patches extended further in the anterior-posterior than in the medial-lateral direction. The expression of these horizontal patchy connections is age- and experience-dependent. From ten days to six weeks of age patches are exuberant and on occasion fuse to beaded bands extending radially from the injection site. From 6 weeks onwards the number and the tangential spread of the patches decreases to one or two rows of isolated clusters. Long-term binocular deprivation disrupts this pattern of intrinsic connections nearly completely. We infer from these results that there is an inborn pattern of discrete horizontal connections in striate cortex which is shaped by visual experience and requires contour vision for its maintenance. 相似文献
20.
In rats ranging in age from the second postnatal day (23rd postconceptional day 23 PCD) to adulthood, we have studied the distribution of corticotectal terminals labelled anterogradely by unilateral injections of horseradish peroxidase (conjugated with wheat germ agglutinin) into the visual or motor cortices. No projection to the contralateral superior colliculus (SC) was observed. The earliest age at which the labelled axons and/or terminals from the visual cortex were observed in the ipsilateral SC was 25 PCD. At this stage the projection only involves the optic layer. From 28 to 34 PCD, the projection involves the optic layer, the intermediate layers and the deep part of superficial gray layer. Between 34 and 40 PCD the projection becomes restricted to the superficial laminae (i.e. adultlike). On the 23 PCD (the earliest age examined) we observed a projection from the motor cortex to the intermediate laminae and to a lesser extent the optic layer of the ipsilateral SC. By 34 PCD only the adult-like projection extending from the brachium to the periaqueductal gray (PAG) is apparent. The disappearance of the transient projections to the intermediate collicular laminae may be the result of withdrawal of ‘misprojecting’ axonal collaterals. 相似文献