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Suzanne N. Haber - One of the best experts on this subject based on the ideXlab platform.
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Defining the Caudal Ventral Striatum in Primates: Cellular and Histochemical Features
The Journal of Neuroscience, 2002Co-Authors: Julie L. Fudge, Suzanne N. HaberAbstract:Afferents from the amygdala help to define the ventral Striatum and mediate goal-directed behaviors. In addition to well known inputs to the classic ventral Striatum, the amygdala also projects to the caudoventral Striatum and amygdalostriatal area. We examined whether the primate caudoventral Striatum and amygdalostriatal area can be considered part of the “ventral” Striatum based on cellular and histochemical features found in the classic rostral ventral Striatum. We used several histochemical stains, including calbindin-D28k, a marker of the shell compartment, acetylcholinesterase, substance P, tyrosine hydroxylase, and Bcl-2, a marker of immature neurons, to examine this question. Our results indicate that the lateral amygdalostriatal area and caudoventral Striatum are “striatal like” based on intermediate to high acetylcholinesterase and tyrosine hydroxylase levels. The lateral amygdalostriatal area is chemically similar to the shell, whereas the caudoventral Striatum more closely resembles the Striatum outside the shell. In contrast, the medial amygdalostriatal area is more related to the central amygdaloid nucleus than to the Striatum. Bcl-2 immunoreactivity is associated with granular islands and medium-sized cells in the vicinity of the ventral Striatum both rostrally and caudally. Together, the caudal ventral Striatum has a histochemical and cellular organization similar to that of the rostral ventral Striatum, consistent with their common innervation by the amygdala and other ventral structures. In addition, Bcl-2 is expressed in and near both poles of the ventral Striatum, suggesting that these areas maintain a heightened capacity for growth and plasticity compared with other striatal sectors.
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Topographic organization of the ventral Striatum afferent projection from amygdaloid complex and hippocampal formation
Nō to shinkei Brain and nerve, 1996Co-Authors: Katsuzo Kunishio, Ohmoto T, Suzanne N. HaberAbstract:The organization of the striatal afferent fibers from the amygdaloid complex and hippocampal formation was studied in the monkey with particular emphasis on specific projections of the ventral Striatum. Retrograde tracers were injected into the different regions of the ventral (limbic) Striatum and dorsolateral (sensorimotor) Striatum. Labeled neurons were observed in the various regions of the amygdaloid complex and hippocampal formation. The medial ventral Striatum received dense projections from the amygdala (the basal nucleus and the magnocellular division of the accessory basal nucleus), and the hippocampus (subiculum, CA1 and CA3). The shell of the nucleus accumbens (calbindin-D28k negative region) also received dense projections from the amygdala (the basal nucleus and the magnocellular division of the accessory basal nucleus), and the hippocampus (subiculum). The injections into the core of the nucleus accumbens showed scattered labeled neurons in the amygdala, and only a few labeled neurons in the hippocampus. The lateral ventral Striatum received few inputs from the amygdala and hippocampus. In contrast to the ventral Striatum, the dorsolateral Striatum received no projection from the amygdala or the hippocampus. The connectional similarities between the medial ventral Striatum and the shell of the nucleus accumbens suggest that although the medial ventral Striatum is not calbindin-D28k negative, it may be regarded as a transitional zone between the shell and the rest of the ventral Striatum.
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Primate striatonigral projections: a comparison of the sensorimotor-related Striatum and the ventral Striatum.
The Journal of Comparative Neurology, 1994Co-Authors: E. Lynd-balta, Suzanne N. HaberAbstract:The Striatum receives topographic cortical inputs with the limbic lobe terminating in the ventral Striatum and sensorimotor cortical regions terminating in the dorsolateral Striatum. The organization of striatonigral projections originating from these different striatal territories was examined in primate by using several anterograde tracers. The ventral Striatum innervates a large area of the substantia nigra, including the medial pars reticulata and much of the pars compacta. Moreover, projections from separate areas of the ventral Striatum overlap considerably in the substantia nigra. No mediolateral or rostrocaudal topographic order is apparent, and the area of the substantia nigra associated with the ventral Striatum is extensive. In contrast, the sensorimotor-related Striatum innervates a limited region of the ventrolateral substantia nigra. Similar to ventral striatonigral projections, projections originating from different areas of the sensorimotor-related Striatum send converging inputs to the substantia nigra. Sensorimotor-related striatonigral projections avoid the region of the dopaminergic neurons in the dorsal pars compacta. Striatonigral projections from the sensorimotor-related and ventral Striatum do not overlap in the substantia nigra. Examination of the outputs of discrete striatal loci indicates that the organization of striatonigral projections is more related to corticostriatal inputs than to a simple rostrocaudal, dorsoventral, or mediolateral tpography of the Striatum. Striatal projections that originate from different striatal territories are distinct and nonoverlapping, thus supporting the concept of segregated striatonigral circuits. However, areas of the Striatum that receive common cortical inputs send converging inputs to the substantia nigra. This suggests that the substantia nigra is also an important link for integrating information between functionally related (sub)circuits. © 1994 Wiley-Liss, Inc.
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Primate striatonigral projections: a comparison of the sensorimotor-related Striatum and the ventral Striatum.
The Journal of comparative neurology, 1994Co-Authors: E. Lynd-balta, Suzanne N. HaberAbstract:The Striatum receives topographic cortical inputs with the limbic lobe terminating in the ventral Striatum and sensorimotor cortical regions terminating in the dorsolateral Striatum. The organization of striatonigral projections originating from these different striatal territories was examined in primate by using several anterograde tracers. The ventral Striatum innervates a large area of the substantia nigra, including the medial pars reticulata and much of the pars compacta. Moreover, projections from separate areas of the ventral Striatum overlap considerably in the substantia nigra. No mediolateral or rostrocaudal topographic order is apparent, and the area of the substantia nigra associated with the ventral Striatum is extensive. In contrast, the sensorimotor-related Striatum innervates a limited region of the ventrolateral substantia nigra. Similar to ventral striatonigral projections, projections originating from different areas of the sensorimotor-related Striatum send converging inputs to the substantia nigra. Sensorimotor-related striatonigral projections avoid the region of the dopaminergic neurons in the dorsal pars compacta. Striatonigral projections from the sensorimotor-related and ventral Striatum do not overlap in the substantia nigra. Examination of the outputs of discrete striatal loci indicates that the organization of striatonigral projections is more related to corticostriatal inputs than to a simple rostrocaudal, dorsoventral, or mediolateral topography of the Striatum. Striatal projections that originate from different striatal territories are distinct and nonoverlapping, thus supporting the concept of segregated striatonigral circuits. However, areas of the Striatum that receive common cortical inputs send converging inputs to the substantia nigra. This suggests that the substantia nigra is also an important link for integrating information between functionally related (sub)circuits.
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The organization of midbrain projections to the Striatum in the primate: Sensorimotor-related Striatum versus ventral Striatum
Neuroscience, 1994Co-Authors: E. Lynd-balta, Suzanne N. HaberAbstract:Abstract In order to examine the organization of nigrostriatal projections in the primate, the retrograde tracers Lucifer Yellow conjugated to dextran amines and horseradish peroxidase conjugated to wheatgerm agglutinin were injected into different regions of the dorsolateral and ventral Striatum. Based on the topography of cortical inputs to the Striatum, the dorsolateral Striatum is associated with the motor system, and the ventral Striatum is related to the limbic system. Our results indicate that although midbrain neurons projecting to the ventral and dorsolateral Striatum are mostly separate, there are neurons projecting to these different striatal territories that overlap in the medial substantia nigra. The dopaminergic neurons of the ventral mesencephalon can be subdivided into dorsal and ventral tiers that include the cells of the ventral tegmental area, the substantia nigra pars compacta, and the retrorubral area. Neurons projecting to the ventral Striatum are found in both the dorsal and ventral tiers. A large number of neurons occupying the medial densocellular zone of the ventral tier are labeled following injections into different regions of the ventral Striatum. Neurons projecting to the sensorimotor-related Striatum are derived almost exclusively from the ventral tier. Many of these neurons are located very ventrally in the substantia nigra, where clusters of neurons invade the pars reticulata. In addition, labeled neurons are found throughout the mediolateral extent of the densocellular zone of the pars compacta. Notably, neurons are labeled in the medial densocelluar zone following injections into the dorsolateral and ventral Striatum. Mesencephalic neurons projecting to different striatal territories are distinct in that dorsal tier neurons mainly innervate the ventral Striatum, whereas the ventral columns of neurons in the ventral tier innervate the sensorimotor-related Striatum. Thus, the dopaminergic regulation of the sensorimotor-related Striatum and the ventral Striatum may be different. However, a subgroup of dopaminergic neurons in the medial densocellular zone projects to both striatal territories. Such divergent projections may allow the substantia nigra to serve as a link, connecting different striatal territories, via their connections with the substantia nigra.
E. Lynd-balta - One of the best experts on this subject based on the ideXlab platform.
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Primate striatonigral projections: a comparison of the sensorimotor-related Striatum and the ventral Striatum.
The Journal of Comparative Neurology, 1994Co-Authors: E. Lynd-balta, Suzanne N. HaberAbstract:The Striatum receives topographic cortical inputs with the limbic lobe terminating in the ventral Striatum and sensorimotor cortical regions terminating in the dorsolateral Striatum. The organization of striatonigral projections originating from these different striatal territories was examined in primate by using several anterograde tracers. The ventral Striatum innervates a large area of the substantia nigra, including the medial pars reticulata and much of the pars compacta. Moreover, projections from separate areas of the ventral Striatum overlap considerably in the substantia nigra. No mediolateral or rostrocaudal topographic order is apparent, and the area of the substantia nigra associated with the ventral Striatum is extensive. In contrast, the sensorimotor-related Striatum innervates a limited region of the ventrolateral substantia nigra. Similar to ventral striatonigral projections, projections originating from different areas of the sensorimotor-related Striatum send converging inputs to the substantia nigra. Sensorimotor-related striatonigral projections avoid the region of the dopaminergic neurons in the dorsal pars compacta. Striatonigral projections from the sensorimotor-related and ventral Striatum do not overlap in the substantia nigra. Examination of the outputs of discrete striatal loci indicates that the organization of striatonigral projections is more related to corticostriatal inputs than to a simple rostrocaudal, dorsoventral, or mediolateral tpography of the Striatum. Striatal projections that originate from different striatal territories are distinct and nonoverlapping, thus supporting the concept of segregated striatonigral circuits. However, areas of the Striatum that receive common cortical inputs send converging inputs to the substantia nigra. This suggests that the substantia nigra is also an important link for integrating information between functionally related (sub)circuits. © 1994 Wiley-Liss, Inc.
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Primate striatonigral projections: a comparison of the sensorimotor-related Striatum and the ventral Striatum.
The Journal of comparative neurology, 1994Co-Authors: E. Lynd-balta, Suzanne N. HaberAbstract:The Striatum receives topographic cortical inputs with the limbic lobe terminating in the ventral Striatum and sensorimotor cortical regions terminating in the dorsolateral Striatum. The organization of striatonigral projections originating from these different striatal territories was examined in primate by using several anterograde tracers. The ventral Striatum innervates a large area of the substantia nigra, including the medial pars reticulata and much of the pars compacta. Moreover, projections from separate areas of the ventral Striatum overlap considerably in the substantia nigra. No mediolateral or rostrocaudal topographic order is apparent, and the area of the substantia nigra associated with the ventral Striatum is extensive. In contrast, the sensorimotor-related Striatum innervates a limited region of the ventrolateral substantia nigra. Similar to ventral striatonigral projections, projections originating from different areas of the sensorimotor-related Striatum send converging inputs to the substantia nigra. Sensorimotor-related striatonigral projections avoid the region of the dopaminergic neurons in the dorsal pars compacta. Striatonigral projections from the sensorimotor-related and ventral Striatum do not overlap in the substantia nigra. Examination of the outputs of discrete striatal loci indicates that the organization of striatonigral projections is more related to corticostriatal inputs than to a simple rostrocaudal, dorsoventral, or mediolateral topography of the Striatum. Striatal projections that originate from different striatal territories are distinct and nonoverlapping, thus supporting the concept of segregated striatonigral circuits. However, areas of the Striatum that receive common cortical inputs send converging inputs to the substantia nigra. This suggests that the substantia nigra is also an important link for integrating information between functionally related (sub)circuits.
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The organization of midbrain projections to the Striatum in the primate: Sensorimotor-related Striatum versus ventral Striatum
Neuroscience, 1994Co-Authors: E. Lynd-balta, Suzanne N. HaberAbstract:Abstract In order to examine the organization of nigrostriatal projections in the primate, the retrograde tracers Lucifer Yellow conjugated to dextran amines and horseradish peroxidase conjugated to wheatgerm agglutinin were injected into different regions of the dorsolateral and ventral Striatum. Based on the topography of cortical inputs to the Striatum, the dorsolateral Striatum is associated with the motor system, and the ventral Striatum is related to the limbic system. Our results indicate that although midbrain neurons projecting to the ventral and dorsolateral Striatum are mostly separate, there are neurons projecting to these different striatal territories that overlap in the medial substantia nigra. The dopaminergic neurons of the ventral mesencephalon can be subdivided into dorsal and ventral tiers that include the cells of the ventral tegmental area, the substantia nigra pars compacta, and the retrorubral area. Neurons projecting to the ventral Striatum are found in both the dorsal and ventral tiers. A large number of neurons occupying the medial densocellular zone of the ventral tier are labeled following injections into different regions of the ventral Striatum. Neurons projecting to the sensorimotor-related Striatum are derived almost exclusively from the ventral tier. Many of these neurons are located very ventrally in the substantia nigra, where clusters of neurons invade the pars reticulata. In addition, labeled neurons are found throughout the mediolateral extent of the densocellular zone of the pars compacta. Notably, neurons are labeled in the medial densocelluar zone following injections into the dorsolateral and ventral Striatum. Mesencephalic neurons projecting to different striatal territories are distinct in that dorsal tier neurons mainly innervate the ventral Striatum, whereas the ventral columns of neurons in the ventral tier innervate the sensorimotor-related Striatum. Thus, the dopaminergic regulation of the sensorimotor-related Striatum and the ventral Striatum may be different. However, a subgroup of dopaminergic neurons in the medial densocellular zone projects to both striatal territories. Such divergent projections may allow the substantia nigra to serve as a link, connecting different striatal territories, via their connections with the substantia nigra.
Roshan Cools - One of the best experts on this subject based on the ideXlab platform.
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Dissociable responses to punishment in distinct striatal regions during reversal learning
NeuroImage, 2010Co-Authors: Oliver J. Robinson, Michael J. Frank, Barbara J. Sahakian, Roshan CoolsAbstract:Adaptive behavior depends on the ability to flexibly alter our choices in response to changes in reward and punishment contingencies. One brain region frequently implicated in such behavior is the Striatum. However, this region is functionally diverse and there are a number of apparent inconsistencies across previous studies. For instance, how can significant BOLD responses in the ventral Striatum during punishment-based reversal learning be reconciled with the frequently demonstrated role of the ventral Striatum in reward processing? Here we attempt to address this question by separately examining BOLD responses during reversal learning driven by reward and during reversal learning driven by punishment. We demonstrate simultaneous valence-specific and valence-nonspecific signals in the Striatum, with the posterior dorsal Striatum responding only to unexpected reward, and the anterior ventral Striatum responding to both unexpected punishment as well as unexpected reward. These data help to reconcile conflicting findings from previous studies by showing that distinct regions of the Striatum exhibit dissociable responses to punishment during reversal learning.
Robert J Mcdonald - One of the best experts on this subject based on the ideXlab platform.
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dorsal Striatum and stimulus response learning lesions of the dorsolateral but not dorsomedial Striatum impair acquisition of a stimulus response based instrumental discrimination task while sparing conditioned place preference learning
Neuroscience, 2004Co-Authors: Robert E Featherstone, Robert J McdonaldAbstract:While some evidence suggests that the dorsal Striatum is important for stimulus-response learning, disagreement exists about the relative contribution of the dorsolateral and dorsomedial Striatum to this form of learning. In the present experiment, the effects of lesions of the dorsolateral and dorsomedial Striatum were investigated on two tasks that differentially require the development of stimulus-response learning. The first task utilized an operant conditional discrimination task, which is likely to rely heavily upon stimulus-response learning. The second task looked conditioned place preference learning, a task that is unlikely to require the development of stimulus-response associations. Animals with lesions of the dorsolateral Striatum were impaired on the operant conditional discrimination task, but retained the ability to learn the conditioned place preference task. In contrast, animals with lesions of the dorsomedial Striatum were not found to be impaired on either task used in the present experiment. These results suggest that the dorsolateral Striatum is necessary for the successful acquisition of tasks that place a demand upon stimulus-response learning, while the dorsomedial Striatum is not involved in this type of learning.
Vincent D Costa - One of the best experts on this subject based on the ideXlab platform.
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Motivational neural circuits underlying reinforcement learning
Nature Neuroscience, 2017Co-Authors: Bruno B Averbeck, Vincent D CostaAbstract:Reinforcement learning (RL) is the behavioral process of learning to associate rewards with actions or objects. Conceptual and theoretical accounts of RL have focused on the Striatum. However, recent data shows that the amygdala also plays an important role in RL. Reinforcement learning (RL) is the behavioral process of learning the values of actions and objects. Most models of RL assume that the dopaminergic prediction error signal drives plasticity in frontal–striatal circuits. The Striatum then encodes value representations that drive decision processes. However, the amygdala has also been shown to play an important role in forming Pavlovian stimulus–outcome associations. These Pavlovian associations can drive motivated behavior via the amygdala projections to the ventral Striatum or the ventral tegmental area. The amygdala may, therefore, play a central role in RL. Here we compare the contributions of the amygdala and the Striatum to RL and show that both the amygdala and Striatum learn and represent expected values in RL tasks. Furthermore, value representations in the Striatum may be inherited, to some extent, from the amygdala. The Striatum may, therefore, play less of a primary role in learning stimulus–outcome associations in RL than previously suggested.
