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Jon H. Kaas - One of the best experts on this subject based on the ideXlab platform.
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frontal eye field in prosimian galagos intracortical microstimulation and tracing studies
The Journal of Comparative Neurology, 2018Co-Authors: Iwona Stepniewska, Pierre Pouget, Jon H. KaasAbstract:The frontal eye field (FEF) in prosimian primates was identified as a small cortical region, above and Anterior to the Anterior frontal sulcus, from which saccadic eye movements were evoked with electrical stimulation. Tracer injections revealed FEF connections with cortical and subcortical structures participating in higher order visual processing. Ipsilateral cortical connections were the densest with adjoining parts of the dorsal premotor and prefrontal cortex (PFC). Label in a region corresponding to supplementary eye field (SEF) of other primates, suggests the existence of SEF in galagos. Other connections were with Ventral premotor cortex (PMV), the caudal half of posterior parietal cortex, cingulate cortex, visual areas within the superior temporal sulcus, and inferotemporal cortex. Callosal connections were mostly with the region of the FEF of another hemisphere, SEF, PFC and PMV. Most subcortical connections were ipsilateral, but some were bilateral. Dense bilateral connections were to caudate nuclei. Densest reciprocal ipsilateral connections were with the paralamellar portion of mediodorsal Nucleus, intralaminar nuclei and magnocellular portion of Ventral Anterior Nucleus. Other FEF connections were with the claustrum, reticular Nucleus, zona incerta, lateral posterior and medial pulvinar nuclei, Nucleus limitans, pretectal area, Nucleus of Darkschewitsch, mesencephalic and pontine reticular formation and pontine nuclei. Surprisingly, the superior colliculus (SC) contained only sparse anterograde label. Although most FEF connections in galagos are similar to those in monkeys, the FEF-SC connections appear to be much less. This suggests that a major contribution of the FEF to visuomotor functions of SC emerged with the evolution of anthropoid primates. This article is protected by copyright. All rights reserved.
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Frontal eye field in prosimian galagos: Intracortical microstimulation and tracing studies
The Journal of comparative neurology, 2017Co-Authors: Iwona Stepniewska, Pierre Pouget, Jon H. KaasAbstract:The frontal eye field (FEF) in prosimian primates was identified as a small cortical region, above and Anterior to the Anterior frontal sulcus, from which saccadic eye movements were evoked with electrical stimulation. Tracer injections revealed FEF connections with cortical and subcortical structures participating in higher order visual processing. Ipsilateral cortical connections were the densest with adjoining parts of the dorsal premotor and prefrontal cortex (PFC). Label in a region corresponding to supplementary eye field (SEF) of other primates, suggests the existence of SEF in galagos. Other connections were with Ventral premotor cortex (PMV), the caudal half of posterior parietal cortex, cingulate cortex, visual areas within the superior temporal sulcus, and inferotemporal cortex. Callosal connections were mostly with the region of the FEF of another hemisphere, SEF, PFC, and PMV. Most subcortical connections were ipsilateral, but some were bilateral. Dense bilateral connections were to caudate nuclei. Densest reciprocal ipsilateral connections were with the paralamellar portion of mediodorsal Nucleus, intralaminar nuclei and magnocellular portion of Ventral Anterior Nucleus. Other FEF connections were with the claustrum, reticular Nucleus, zona incerta, lateral posterior and medial pulvinar nuclei, Nucleus limitans, pretectal area, Nucleus of Darkschewitsch, mesencephalic and pontine reticular formation and pontine nuclei. Surprisingly, the superior colliculus (SC) contained only sparse anterograde label. Although most FEF connections in galagos are similar to those in monkeys, the FEF-SC connections appear to be much less. This suggests that a major contribution of the FEF to visuomotor functions of SC emerged with the evolution of anthropoid primates.
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The thalamic connections of motor, premotor, and prefrontal areas of cortex in a prosimian primate (Otolemur garnetti).
Neuroscience, 2006Co-Authors: Pei-chun Fang, Iwona Stepniewska, Jon H. KaasAbstract:Connections of motor areas in the frontal cortex of prosimian galagos (Otolemur garnetti) were determined by injecting tracers into sites identified by microstimulation in the primary motor area (M1), dorsal premotor area (PMD), Ventral premotor area (PMV), supplementary motor area (SMA), frontal eye field (FEF), and granular frontal cortex. Retrogradely labeled neurons for each injection were related to architectonically defined thalamic nuclei. Nissl, acetylcholinesterase, cytochrome oxidase, myelin, parvalbumin, calbindin, and Cat 301 preparations allowed the Ventral Anterior and Ventral lateral thalamic regions, parvocellular and magnocellular subdivisions of Ventral Anterior Nucleus, and Anterior and posterior subdivisions of Ventral lateral Nucleus of monkeys to be identified. The results indicate that each cortical area receives inputs from several thalamic nuclei, but the proportions differ. M1 receives major inputs from the posterior subdivision of Ventral lateral Nucleus while premotor areas receive major inputs from Anterior parts of Ventral lateral Nucleus (the Anterior subdivision of Ventral lateral Nucleus and the Anterior portion of posterior subdivision of Ventral lateral Nucleus). PMD and SMA have connections with more dorsal parts of the Ventral lateral Nucleus than PMV. The results suggest that galagos share many subdivisions of the motor thalamus and thalamocortical connection patterns with simian primates, while having less clearly differentiated subdivisions of the motor thalamus.
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Ascending inputs to the pre-supplementary motor area in the macaque monkey: cerebello- and pallido-thalamocortical projections
Thalamus & Related Systems, 2003Co-Authors: Sharleen T. Sakai, Iwona Stepniewska, Jon H. KaasAbstract:The goal of the present study was to determine the ascending sources to the pre-supplementary motor area (pre-SMA) in macaque monkeys using multiple labeling techniques. We labeled the pallidothalamic projections using biotinylated dextran amine (BDA) and the cerebellothalamic projections using wheatgerm agglutinin conjugated to horseradish peroxidase. The pre-SMA thalamocortical projections neurons were also labeled using cholera toxin subunit b following identification of the pre-SMA by location, and by movements evoked by intracortical microstimulation. The extent of pre-SMA was later confirmed by identifying characteristics from Nissl cytoarchitecture and SMI-32 immunoreactivity. Thalamic nuclear boundaries were based on Nissl cytoarchitecture, acetylcholinesterase chemoarchitecture and Cat-301 immunoreactivity. Cerebellothalamic afferents were distributed predominantly to Ventral lateral posterior Nucleus (VLp), including medial and dorsal VLp, while the pallidothalamic afferents projected more rostrally to Ventral lateral Anterior Nucleus (VLa) and Ventral Anterior Nucleus (VA). The pre-SMA thalamocortical projection neurons were primarily found in VA and medial VLp. However, scattered cells were also found in VLa, dorsal VLp, central lateral Nucleus (CL) and mediodorsal Nucleus (MD). Scattered pre-SMA projecting cells overlapped foci of cerebellar label in medial VLp. Additionally, limited overlap of pre-SMA cells and pallidothalamic labeling was found in caudal VA. These findings suggest that the pre-SMA is uniquely positioned to integrate ascending basal ganglia and cerebellar information after a relay from VA and medial VLp. These anatomical findings are consistent with the recent hypothesis that the pre-SMA acts as the coordinator of visual and motor loops in motor learning [J. Cogn. Neurosci. 13 (2001) 626].
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Somatosensory input to the ventrolateral thalamic region in the macaque monkey : A potential substrate for parkinsonian tremor
The Journal of comparative neurology, 2002Co-Authors: Iwona Stepniewska, Sharleen T. Sakai, Jon H. KaasAbstract:In the present study, we determined the anatomic relationships between somatosensory and motor pathways within ventrolateral (VL) thalamic nuclei of the motor thalamus of macaque monkeys. In labeling experiments, four macaque monkeys (Macaca mulatta) received injections of biotinylated dextran amine and wheat germ agglutinin conjugated to horseradish peroxidase into the cerebellar nuclei or internal segment of the globus pallidus and cervical segments of the spinal cord, respectively. Each tracer was visualized in brain sections by sequentially using a different chromogen. Labeled terminals were plotted and superimposed on adjacent brain sections processed for Nissl substance, acetylcholinesterase, and the antigens for calbindin and Cat-301 to reveal thalamic nuclei. The labeled cerebellar terminals were distributed throughout the posterior VL (VLp), whereas the labeled pallidothalamic terminals were concentrated in the Anterior VL and the Ventral Anterior Nucleus. The spinothalamic input was directed mostly to the Ventral posterior complex and cells just caudal to it. In addition, the patches of spinothalamic terminations intermingled and partly overlapped with the cerebellothalamic, but not with the pallidothalamic terminations within VLp. The regions of overlap of somatosensory and cerebellar inputs within the VLp of the present study appear to correspond to the reported locations of the tremor-related cells in parkinsonian patients. Thus, the overlapping spinothalamic and cerebellar inputs may provide a substrate for the altered activity of motor thalamic neurons in such patients.
Sharleen T. Sakai - One of the best experts on this subject based on the ideXlab platform.
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Ascending inputs to the pre-supplementary motor area in the macaque monkey: cerebello- and pallido-thalamocortical projections
Thalamus & Related Systems, 2003Co-Authors: Sharleen T. Sakai, Iwona Stepniewska, Jon H. KaasAbstract:The goal of the present study was to determine the ascending sources to the pre-supplementary motor area (pre-SMA) in macaque monkeys using multiple labeling techniques. We labeled the pallidothalamic projections using biotinylated dextran amine (BDA) and the cerebellothalamic projections using wheatgerm agglutinin conjugated to horseradish peroxidase. The pre-SMA thalamocortical projections neurons were also labeled using cholera toxin subunit b following identification of the pre-SMA by location, and by movements evoked by intracortical microstimulation. The extent of pre-SMA was later confirmed by identifying characteristics from Nissl cytoarchitecture and SMI-32 immunoreactivity. Thalamic nuclear boundaries were based on Nissl cytoarchitecture, acetylcholinesterase chemoarchitecture and Cat-301 immunoreactivity. Cerebellothalamic afferents were distributed predominantly to Ventral lateral posterior Nucleus (VLp), including medial and dorsal VLp, while the pallidothalamic afferents projected more rostrally to Ventral lateral Anterior Nucleus (VLa) and Ventral Anterior Nucleus (VA). The pre-SMA thalamocortical projection neurons were primarily found in VA and medial VLp. However, scattered cells were also found in VLa, dorsal VLp, central lateral Nucleus (CL) and mediodorsal Nucleus (MD). Scattered pre-SMA projecting cells overlapped foci of cerebellar label in medial VLp. Additionally, limited overlap of pre-SMA cells and pallidothalamic labeling was found in caudal VA. These findings suggest that the pre-SMA is uniquely positioned to integrate ascending basal ganglia and cerebellar information after a relay from VA and medial VLp. These anatomical findings are consistent with the recent hypothesis that the pre-SMA acts as the coordinator of visual and motor loops in motor learning [J. Cogn. Neurosci. 13 (2001) 626].
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Somatosensory input to the ventrolateral thalamic region in the macaque monkey : A potential substrate for parkinsonian tremor
The Journal of comparative neurology, 2002Co-Authors: Iwona Stepniewska, Sharleen T. Sakai, Jon H. KaasAbstract:In the present study, we determined the anatomic relationships between somatosensory and motor pathways within ventrolateral (VL) thalamic nuclei of the motor thalamus of macaque monkeys. In labeling experiments, four macaque monkeys (Macaca mulatta) received injections of biotinylated dextran amine and wheat germ agglutinin conjugated to horseradish peroxidase into the cerebellar nuclei or internal segment of the globus pallidus and cervical segments of the spinal cord, respectively. Each tracer was visualized in brain sections by sequentially using a different chromogen. Labeled terminals were plotted and superimposed on adjacent brain sections processed for Nissl substance, acetylcholinesterase, and the antigens for calbindin and Cat-301 to reveal thalamic nuclei. The labeled cerebellar terminals were distributed throughout the posterior VL (VLp), whereas the labeled pallidothalamic terminals were concentrated in the Anterior VL and the Ventral Anterior Nucleus. The spinothalamic input was directed mostly to the Ventral posterior complex and cells just caudal to it. In addition, the patches of spinothalamic terminations intermingled and partly overlapped with the cerebellothalamic, but not with the pallidothalamic terminations within VLp. The regions of overlap of somatosensory and cerebellar inputs within the VLp of the present study appear to correspond to the reported locations of the tremor-related cells in parkinsonian patients. Thus, the overlapping spinothalamic and cerebellar inputs may provide a substrate for the altered activity of motor thalamic neurons in such patients.
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The relationship between MI and SMA afferents and cerebellar and pallidal efferents in the macaque monkey.
Somatosensory & motor research, 2002Co-Authors: Sharleen T. Sakai, Masahiko Inase, Jun TanjiAbstract:The purpose of the present study was to determine the interrelationship between the thalamic afferents arising from the cerebellum (Cb) and the internal segment of the globus pallidus (GPi) with the neurons projecting to the primary motor cortex (MI) and to the supplementary motor area (SMA). We combined fluorescent retrograde tracers with a double anterograde labeling technique. Multiple injections of a combination of Diamidino Yellow and Fast Blue were made into either the MI or SMA hand/arm representation as determined by intracortical microstimulation. In the same animal, biotinylated dextran amine was injected into the GPi and horseradish peroxidase conjugated to wheat germ agglutinin was injected into the contralateral cerebellar nuclei. The results revealed that the cerebellar and pallidal thalamic territories are largely separate. The Ventral Anterior Nucleus (VA) and the Ventral lateral Nucleus pars oralis (VLo) contained a greater density of pallidal labeling while a greater density of cerebella...
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Pallidal and cerebellar afferents to pre-supplementary motor area thalamocortical neurons in the owl monkey: A multiple labeling study
The Journal of comparative neurology, 2000Co-Authors: Sharleen T. Sakai, Iwona Stepniewska, Jon H. KaasAbstract:In the present study, we determined where thalamic neurons projecting to the pre-supplementary motor area (pre-SMA) are located relative to pallidothalamic and cerebellothalamic inputs and nuclear boundaries. We employed a triple-labeling technique in the same owl monkey (Aotus trivirgatus). The cerebellothalamic projections were labeled with injections of wheat germ agglutinin conjugated to horseradish peroxidase, and the pallidothalamic projections were labeled with biotinylated dextran amine. The pre-SMA was identified by location and movement patterns evoked by intracortical microstimulation and injected with the retrograde tracer cholera toxin subunit B. Brain sections were processed sequentially using different chromogens to visualize all three tracers in the same section. Alternate sections were processed for Nissl cytoarchitecture or acetylcholinesterase chemoarchitecture for nuclear boundaries. The cerebellar nuclei primarily projected to posterior (VLp), medial (VLx), and dorsal (VLd) divisions of the Ventral lateral Nucleus; the pallidum largely projected to the Anterior division (VLa) of the Ventral lateral Nucleus and the parvocellular part of the Ventral Anterior Nucleus (VApc). However, we also found zones of overlapping projections, as well as interdigitating foci of pallidal and cerebellar label, particularly in border regions of the VLa and VApc. Thalamic neurons labeled by pre-SMA injections occupied a wide band and were especially concentrated in the VLx and VApc, cerebellar and pallidal territories, respectively. Labeled thalamocortical neurons overlapped cerebellar inputs in the VLd and VApc and overlapped pallidal inputs in the VLa and the Ventral medial Nucleus. The results demonstrate that inputs from both the cerebellum and globus pallidus are relayed to the pre-SMA.
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Pallidal and cerebellar inputs to thalamocortical neurons projecting to the supplementary motor area in Macaca fuscata: a triple-labeling light microcopic study
Anatomy and embryology, 1999Co-Authors: Sharleen T. Sakai, Masahiko Inase, Jun TanjiAbstract:We investigated the interrelationship between the supplementary motor area (SMA) thalamocortical projection neurons and the pallidothalamic and cerebellothalamic territories in the monkey (Macaca fuscata) using a combination of three tracers in a triple labeling paradigm. Thalamic labeling was analyzed following injections of the anterograde tracers, biotinylated dextran amine (BDA) into the internal segment of the globus pallidus (GPi) and wheat germ agglutinin conjugated to horseradish peroxidase (WGA-HRP) into the contralateral cerebellar interpositus and dentate nuclei. In addition, the retrograde tracer cholera toxin subunit B (CTB) was injected into the physiologically identified hand/arm representation of SMA. The tissue was processed sequentially using different chromogens in order to visualize all three tracers in a single section. We found that the SMA thalamocortical neurons occupied a wide band extending from the Ventral Anterior Nucleus pars principalis (VApc) through the Ventral lateral Nucleus pars oralis (VLo) and the Ventral lateral Nucleus pars medialis (VLm) and into to the Ventral lateral Nucleus pars caudalis (VLc) including a portion of Ventral posterior lateral Nucleus pars oralis (VPLo) and Nucleus X. The heaviest CTB labeling was found in VLo with dense plexuses of BDA labeled pallidothalamic fibers and swellings often observed superimposed upon retrogradely labeled CTB cells. In addition, dense foci of cerebellothalamic WGA-HRP anterograde label were observed coinciding with the occasional retrogradely CTB labeled neurons in VLc and transitional zones between VApc, VLo and VPLo. Our light microscopic results suggest that the SMA receives thalamic inputs with afferents largely derived from GPi and minor inputs originating from the cerebellum.
Suzanne N. Haber - One of the best experts on this subject based on the ideXlab platform.
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Organization of thalamic projections to the Ventral striatum in the primate
The Journal of Comparative Neurology, 1995Co-Authors: José Manuel Giménez-amaya, Silvano De Las Heras, Nikolaus R Mcfarland, Suzanne N. HaberAbstract:Although thalamic projections to the dorsal striatum are well described in primates and other species, little is known about thalamic projections to the Ventral or “limbic” striatum in the primate. This study explores the organization of the thalamic projections to the Ventral striatum in the primate brain by means of wheat germ agglutinin conjugated to horseradish peroxidase (WGA-HRP) and Lucifer yellow (LY) retrograde tracer techniques. In addition, because functional and connective differences have been described for the core and shell components of the Nucleus accumbens in the rat and are thought to be similar in the primate, this study also explores whether these regions of the Nucleus accumbens can be distinguished by their thalamic input. Tracer injections are placed in different portions of the Ventral striatum, including the medial and lateral regions of the Ventral striatum; the central region of the Ventral striatum, including the dorsal part of the core of the Nucleus accumbens; and the shell region of the Nucleus accumbens. Retrogradely labeled neurons are located mainly in the midline nuclear group (Anterior and posterior paraventricular, paratenial, rhomboid, and reuniens thalamic nuclei) and in the parafascicular thalamic Nucleus. Additional labeled cells are found in other portions of the intralaminar nuclear group as well as in other thalamic nuclei in the Ventral, Anterior, medial, lateral, and posterior thalamic nuclear groups. The distribution of labeled cells varies depending on the area of the Ventral striatum injected. All regions of the Ventral striatum receive strong projections from the midline thalamic nuclei and from the parafascicular Nucleus. In addition, the medial region of the Ventral striatum receives numerous projections from the central superior lateral Nucleus, the magnocellular subdivision of the Ventral Anterior Nucleus, and parts of the mediodorsal Nucleus. After injection into the lateral region of the Ventral striatum, few labeled neurons are seen scattered in nuclei of the intralaminar and Ventral thalamic groups and occasional labeled cells in the mediodorsal Nucleus. The central region of the Ventral striatum, including the dorsal part of the core of the Nucleus accumbens, receives a limited projection from the midline thqlamic, predominantly from the rhomboid Nucleus. It receives much smaller projections from the central medial Nucleus and the Ventral, Anterior, and medial thalamic groups. The shell of the Nucleus accumbens receives the most limited projection from the thalamus and is innervated almost exclusively by the midline thalamic nuclei and the central medial and parafascicular nuclei. The shell is distinguished from the rest of the Ventral striatum in that it receives the fewest projections from the Ventral, Anterior, medial, and lateral thalamic nuclei. © 1995 Wiley-Liss, Inc.
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Organization of thalamic projections to the Ventral striatum in the primate
The Journal of comparative neurology, 1995Co-Authors: José Manuel Giménez-amaya, Nikolaus R Mcfarland, S. De Las Heras, Suzanne N. HaberAbstract:Although thalamic projections to the dorsal striatum are well described in primates and other species, little is known about thalamic projections to the Ventral or "limbic" striatum in the primate. This study explores the organization of the thalamic projections to the Ventral striatum in the primate brain by means of wheat germ agglutinin conjugated to horseradish peroxidase (WGA-HRP) and Lucifer yellow (LY) retrograde tracer techniques. In addition, because functional and connective differences have been described for the core and shell components of the Nucleus accumbens in the rat and are thought to be similar in the primate, this study also explores whether these regions of the Nucleus accumbens can be distinguished by their thalamic input. Tracer injections are placed in different portions of the Ventral striatum, including the medial and lateral regions of the Ventral striatum; the central region of the Ventral striatum, including the dorsal part of the core of the Nucleus accumbens; and the shell region of the Nucleus accumbens. Retrogradely labeled neurons are located mainly in the midline nuclear group (Anterior and posterior paraventricular, paratenial, rhomboid, and reuniens thalamic nuclei) and in the parafascicular thalamic Nucleus. Additional labeled cells are found in other portions of the intralaminar nuclear group as well as in other thalamic nuclei in the Ventral, Anterior, medial, lateral, and posterior thalamic nuclear groups. The distribution of labeled cells varies depending on the area of the Ventral striatum injected. All regions of the Ventral striatum receive strong projections from the midline thalamic nuclei and from the parafascicular Nucleus. In addition, the medial region of the Ventral striatum receives numerous projections from the central superior lateral Nucleus, the magnocellular subdivision of the Ventral Anterior Nucleus, and parts of the mediodorsal Nucleus. After injection into the lateral region of the Ventral striatum, few labeled neurons are seen scattered in nuclei of the intralaminar and Ventral thalamic groups and occasional labeled cells in the mediodorsal Nucleus. The central region of the Ventral striatum, including the dorsal part of the core of the Nucleus accumbens, receives a limited projection from the midline thalamic, predominantly from the rhomboid Nucleus. It receives much smaller projections from the central medial Nucleus and the Ventral, Anterior, and medial thalamic groups. The shell of the Nucleus accumbens receives the most limited projection from the thalamus and is innervated almost exclusively by the midline thalamic nuclei and the central medial and parafascicular nuclei. The shell is distinguished from the rest of the Ventral striatum in that it receives the fewest projections from the Ventral, Anterior, medial, and lateral thalamic nuclei.
José Manuel Giménez-amaya - One of the best experts on this subject based on the ideXlab platform.
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Overlapping territories between the thalamostriatal and nigrothalamic projections in cats.
Neuroreport, 1998Co-Authors: S. De Las Heras, Elisa Mengual, José Manuel Giménez-amayaAbstract:Fluorescent tracers were injected into different regions of the caudate Nucleus and HRP-WGA in the substantia nigra of the cat in order to analyse the thalamic distribution of retrogradely labelled thalamostriatal neurones and anterogradely labelled nigrothalamic terminals within the thalamus. Overlapping thalamic territories between the thalamostriatal neurones projecting to areas of the caudate Nucleus and the nigrothalamic connections were observed in the rostral nuclei of the central thalamic group (Ventral Anterior Nucleus, Ventral Anterior-Ventral lateral complex and Ventral medial Nucleus) and, more restricted, in the rostral (rhomboid, paracentral, Ventral lateral, dorsal mediodorsal nuclei) and caudal intralaminar nuclei (centromedian-parafascicular complex). This study provides evidence of the existence of thalamic areas in which the input and output of the basal ganglia converge.
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Organization of thalamic projections to the Ventral striatum in the primate
The Journal of Comparative Neurology, 1995Co-Authors: José Manuel Giménez-amaya, Silvano De Las Heras, Nikolaus R Mcfarland, Suzanne N. HaberAbstract:Although thalamic projections to the dorsal striatum are well described in primates and other species, little is known about thalamic projections to the Ventral or “limbic” striatum in the primate. This study explores the organization of the thalamic projections to the Ventral striatum in the primate brain by means of wheat germ agglutinin conjugated to horseradish peroxidase (WGA-HRP) and Lucifer yellow (LY) retrograde tracer techniques. In addition, because functional and connective differences have been described for the core and shell components of the Nucleus accumbens in the rat and are thought to be similar in the primate, this study also explores whether these regions of the Nucleus accumbens can be distinguished by their thalamic input. Tracer injections are placed in different portions of the Ventral striatum, including the medial and lateral regions of the Ventral striatum; the central region of the Ventral striatum, including the dorsal part of the core of the Nucleus accumbens; and the shell region of the Nucleus accumbens. Retrogradely labeled neurons are located mainly in the midline nuclear group (Anterior and posterior paraventricular, paratenial, rhomboid, and reuniens thalamic nuclei) and in the parafascicular thalamic Nucleus. Additional labeled cells are found in other portions of the intralaminar nuclear group as well as in other thalamic nuclei in the Ventral, Anterior, medial, lateral, and posterior thalamic nuclear groups. The distribution of labeled cells varies depending on the area of the Ventral striatum injected. All regions of the Ventral striatum receive strong projections from the midline thalamic nuclei and from the parafascicular Nucleus. In addition, the medial region of the Ventral striatum receives numerous projections from the central superior lateral Nucleus, the magnocellular subdivision of the Ventral Anterior Nucleus, and parts of the mediodorsal Nucleus. After injection into the lateral region of the Ventral striatum, few labeled neurons are seen scattered in nuclei of the intralaminar and Ventral thalamic groups and occasional labeled cells in the mediodorsal Nucleus. The central region of the Ventral striatum, including the dorsal part of the core of the Nucleus accumbens, receives a limited projection from the midline thqlamic, predominantly from the rhomboid Nucleus. It receives much smaller projections from the central medial Nucleus and the Ventral, Anterior, and medial thalamic groups. The shell of the Nucleus accumbens receives the most limited projection from the thalamus and is innervated almost exclusively by the midline thalamic nuclei and the central medial and parafascicular nuclei. The shell is distinguished from the rest of the Ventral striatum in that it receives the fewest projections from the Ventral, Anterior, medial, and lateral thalamic nuclei. © 1995 Wiley-Liss, Inc.
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Organization of thalamic projections to the Ventral striatum in the primate
The Journal of comparative neurology, 1995Co-Authors: José Manuel Giménez-amaya, Nikolaus R Mcfarland, S. De Las Heras, Suzanne N. HaberAbstract:Although thalamic projections to the dorsal striatum are well described in primates and other species, little is known about thalamic projections to the Ventral or "limbic" striatum in the primate. This study explores the organization of the thalamic projections to the Ventral striatum in the primate brain by means of wheat germ agglutinin conjugated to horseradish peroxidase (WGA-HRP) and Lucifer yellow (LY) retrograde tracer techniques. In addition, because functional and connective differences have been described for the core and shell components of the Nucleus accumbens in the rat and are thought to be similar in the primate, this study also explores whether these regions of the Nucleus accumbens can be distinguished by their thalamic input. Tracer injections are placed in different portions of the Ventral striatum, including the medial and lateral regions of the Ventral striatum; the central region of the Ventral striatum, including the dorsal part of the core of the Nucleus accumbens; and the shell region of the Nucleus accumbens. Retrogradely labeled neurons are located mainly in the midline nuclear group (Anterior and posterior paraventricular, paratenial, rhomboid, and reuniens thalamic nuclei) and in the parafascicular thalamic Nucleus. Additional labeled cells are found in other portions of the intralaminar nuclear group as well as in other thalamic nuclei in the Ventral, Anterior, medial, lateral, and posterior thalamic nuclear groups. The distribution of labeled cells varies depending on the area of the Ventral striatum injected. All regions of the Ventral striatum receive strong projections from the midline thalamic nuclei and from the parafascicular Nucleus. In addition, the medial region of the Ventral striatum receives numerous projections from the central superior lateral Nucleus, the magnocellular subdivision of the Ventral Anterior Nucleus, and parts of the mediodorsal Nucleus. After injection into the lateral region of the Ventral striatum, few labeled neurons are seen scattered in nuclei of the intralaminar and Ventral thalamic groups and occasional labeled cells in the mediodorsal Nucleus. The central region of the Ventral striatum, including the dorsal part of the core of the Nucleus accumbens, receives a limited projection from the midline thalamic, predominantly from the rhomboid Nucleus. It receives much smaller projections from the central medial Nucleus and the Ventral, Anterior, and medial thalamic groups. The shell of the Nucleus accumbens receives the most limited projection from the thalamus and is innervated almost exclusively by the midline thalamic nuclei and the central medial and parafascicular nuclei. The shell is distinguished from the rest of the Ventral striatum in that it receives the fewest projections from the Ventral, Anterior, medial, and lateral thalamic nuclei.
Iwona Stepniewska - One of the best experts on this subject based on the ideXlab platform.
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frontal eye field in prosimian galagos intracortical microstimulation and tracing studies
The Journal of Comparative Neurology, 2018Co-Authors: Iwona Stepniewska, Pierre Pouget, Jon H. KaasAbstract:The frontal eye field (FEF) in prosimian primates was identified as a small cortical region, above and Anterior to the Anterior frontal sulcus, from which saccadic eye movements were evoked with electrical stimulation. Tracer injections revealed FEF connections with cortical and subcortical structures participating in higher order visual processing. Ipsilateral cortical connections were the densest with adjoining parts of the dorsal premotor and prefrontal cortex (PFC). Label in a region corresponding to supplementary eye field (SEF) of other primates, suggests the existence of SEF in galagos. Other connections were with Ventral premotor cortex (PMV), the caudal half of posterior parietal cortex, cingulate cortex, visual areas within the superior temporal sulcus, and inferotemporal cortex. Callosal connections were mostly with the region of the FEF of another hemisphere, SEF, PFC and PMV. Most subcortical connections were ipsilateral, but some were bilateral. Dense bilateral connections were to caudate nuclei. Densest reciprocal ipsilateral connections were with the paralamellar portion of mediodorsal Nucleus, intralaminar nuclei and magnocellular portion of Ventral Anterior Nucleus. Other FEF connections were with the claustrum, reticular Nucleus, zona incerta, lateral posterior and medial pulvinar nuclei, Nucleus limitans, pretectal area, Nucleus of Darkschewitsch, mesencephalic and pontine reticular formation and pontine nuclei. Surprisingly, the superior colliculus (SC) contained only sparse anterograde label. Although most FEF connections in galagos are similar to those in monkeys, the FEF-SC connections appear to be much less. This suggests that a major contribution of the FEF to visuomotor functions of SC emerged with the evolution of anthropoid primates. This article is protected by copyright. All rights reserved.
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Frontal eye field in prosimian galagos: Intracortical microstimulation and tracing studies
The Journal of comparative neurology, 2017Co-Authors: Iwona Stepniewska, Pierre Pouget, Jon H. KaasAbstract:The frontal eye field (FEF) in prosimian primates was identified as a small cortical region, above and Anterior to the Anterior frontal sulcus, from which saccadic eye movements were evoked with electrical stimulation. Tracer injections revealed FEF connections with cortical and subcortical structures participating in higher order visual processing. Ipsilateral cortical connections were the densest with adjoining parts of the dorsal premotor and prefrontal cortex (PFC). Label in a region corresponding to supplementary eye field (SEF) of other primates, suggests the existence of SEF in galagos. Other connections were with Ventral premotor cortex (PMV), the caudal half of posterior parietal cortex, cingulate cortex, visual areas within the superior temporal sulcus, and inferotemporal cortex. Callosal connections were mostly with the region of the FEF of another hemisphere, SEF, PFC, and PMV. Most subcortical connections were ipsilateral, but some were bilateral. Dense bilateral connections were to caudate nuclei. Densest reciprocal ipsilateral connections were with the paralamellar portion of mediodorsal Nucleus, intralaminar nuclei and magnocellular portion of Ventral Anterior Nucleus. Other FEF connections were with the claustrum, reticular Nucleus, zona incerta, lateral posterior and medial pulvinar nuclei, Nucleus limitans, pretectal area, Nucleus of Darkschewitsch, mesencephalic and pontine reticular formation and pontine nuclei. Surprisingly, the superior colliculus (SC) contained only sparse anterograde label. Although most FEF connections in galagos are similar to those in monkeys, the FEF-SC connections appear to be much less. This suggests that a major contribution of the FEF to visuomotor functions of SC emerged with the evolution of anthropoid primates.
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The thalamic connections of motor, premotor, and prefrontal areas of cortex in a prosimian primate (Otolemur garnetti).
Neuroscience, 2006Co-Authors: Pei-chun Fang, Iwona Stepniewska, Jon H. KaasAbstract:Connections of motor areas in the frontal cortex of prosimian galagos (Otolemur garnetti) were determined by injecting tracers into sites identified by microstimulation in the primary motor area (M1), dorsal premotor area (PMD), Ventral premotor area (PMV), supplementary motor area (SMA), frontal eye field (FEF), and granular frontal cortex. Retrogradely labeled neurons for each injection were related to architectonically defined thalamic nuclei. Nissl, acetylcholinesterase, cytochrome oxidase, myelin, parvalbumin, calbindin, and Cat 301 preparations allowed the Ventral Anterior and Ventral lateral thalamic regions, parvocellular and magnocellular subdivisions of Ventral Anterior Nucleus, and Anterior and posterior subdivisions of Ventral lateral Nucleus of monkeys to be identified. The results indicate that each cortical area receives inputs from several thalamic nuclei, but the proportions differ. M1 receives major inputs from the posterior subdivision of Ventral lateral Nucleus while premotor areas receive major inputs from Anterior parts of Ventral lateral Nucleus (the Anterior subdivision of Ventral lateral Nucleus and the Anterior portion of posterior subdivision of Ventral lateral Nucleus). PMD and SMA have connections with more dorsal parts of the Ventral lateral Nucleus than PMV. The results suggest that galagos share many subdivisions of the motor thalamus and thalamocortical connection patterns with simian primates, while having less clearly differentiated subdivisions of the motor thalamus.
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Ascending inputs to the pre-supplementary motor area in the macaque monkey: cerebello- and pallido-thalamocortical projections
Thalamus & Related Systems, 2003Co-Authors: Sharleen T. Sakai, Iwona Stepniewska, Jon H. KaasAbstract:The goal of the present study was to determine the ascending sources to the pre-supplementary motor area (pre-SMA) in macaque monkeys using multiple labeling techniques. We labeled the pallidothalamic projections using biotinylated dextran amine (BDA) and the cerebellothalamic projections using wheatgerm agglutinin conjugated to horseradish peroxidase. The pre-SMA thalamocortical projections neurons were also labeled using cholera toxin subunit b following identification of the pre-SMA by location, and by movements evoked by intracortical microstimulation. The extent of pre-SMA was later confirmed by identifying characteristics from Nissl cytoarchitecture and SMI-32 immunoreactivity. Thalamic nuclear boundaries were based on Nissl cytoarchitecture, acetylcholinesterase chemoarchitecture and Cat-301 immunoreactivity. Cerebellothalamic afferents were distributed predominantly to Ventral lateral posterior Nucleus (VLp), including medial and dorsal VLp, while the pallidothalamic afferents projected more rostrally to Ventral lateral Anterior Nucleus (VLa) and Ventral Anterior Nucleus (VA). The pre-SMA thalamocortical projection neurons were primarily found in VA and medial VLp. However, scattered cells were also found in VLa, dorsal VLp, central lateral Nucleus (CL) and mediodorsal Nucleus (MD). Scattered pre-SMA projecting cells overlapped foci of cerebellar label in medial VLp. Additionally, limited overlap of pre-SMA cells and pallidothalamic labeling was found in caudal VA. These findings suggest that the pre-SMA is uniquely positioned to integrate ascending basal ganglia and cerebellar information after a relay from VA and medial VLp. These anatomical findings are consistent with the recent hypothesis that the pre-SMA acts as the coordinator of visual and motor loops in motor learning [J. Cogn. Neurosci. 13 (2001) 626].
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Somatosensory input to the ventrolateral thalamic region in the macaque monkey : A potential substrate for parkinsonian tremor
The Journal of comparative neurology, 2002Co-Authors: Iwona Stepniewska, Sharleen T. Sakai, Jon H. KaasAbstract:In the present study, we determined the anatomic relationships between somatosensory and motor pathways within ventrolateral (VL) thalamic nuclei of the motor thalamus of macaque monkeys. In labeling experiments, four macaque monkeys (Macaca mulatta) received injections of biotinylated dextran amine and wheat germ agglutinin conjugated to horseradish peroxidase into the cerebellar nuclei or internal segment of the globus pallidus and cervical segments of the spinal cord, respectively. Each tracer was visualized in brain sections by sequentially using a different chromogen. Labeled terminals were plotted and superimposed on adjacent brain sections processed for Nissl substance, acetylcholinesterase, and the antigens for calbindin and Cat-301 to reveal thalamic nuclei. The labeled cerebellar terminals were distributed throughout the posterior VL (VLp), whereas the labeled pallidothalamic terminals were concentrated in the Anterior VL and the Ventral Anterior Nucleus. The spinothalamic input was directed mostly to the Ventral posterior complex and cells just caudal to it. In addition, the patches of spinothalamic terminations intermingled and partly overlapped with the cerebellothalamic, but not with the pallidothalamic terminations within VLp. The regions of overlap of somatosensory and cerebellar inputs within the VLp of the present study appear to correspond to the reported locations of the tremor-related cells in parkinsonian patients. Thus, the overlapping spinothalamic and cerebellar inputs may provide a substrate for the altered activity of motor thalamic neurons in such patients.
