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| | Notes on the Basal Ganglia |
 | | Because the corticostriatal pathway and the striatopallidal and striatonigral pathways are topographically organized, specific parts of the cortex act on specific parts of the globus pallidus and substantia nigra via the striatum. | | | Major efferents arise in the internal segment of the globus pallidus and the substantia nigra pars reticulata. | | | Thus if dopamine is excitatory to the striatal neurons, the loss of GABA-ergic neurons would lead to an increased firing (disinhibition) of the dopaminergic pathway producing an abnormal outflow from the globus pallidus etc., producing choreic movements. |
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http://www2.umdnj.edu/~paneuweb/basgang.htm
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| | Basal Ganglia Components and Pathways |
| | The indirect pathway is inhibitory from the putamen to the external globus pallidus, inhibitory from there to the subthalamic nucleus, and excitatory to the external globus pallidus or substantia nigra pars reticulata. | | | The inhibitory direct pathway projects monosynaptically from the putamen to the motor regions of the internal globus pallidus and the substantia nigra pars reniculata [84]. | | | It appears that the net affect of the direct pathway is to facilitate motion by exciting the supplementary motor area; the indirect pathway has the opposite effect [32]. |
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http://www.hitl.washington.edu/publications/prothero/node51.html
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| | Parkinson's Disease |
| | Pallidotomy may improve symptoms of tremor, rigidity, and bradykinesia, by interrupting the neural pathway between the globus pallidus and the striatum or thalamus. | | | Pallidotomy is surgery in which the globus pallidus is lesioned. | | | The direct pathway is the inhibitory striatal projection to the globus pallidus interna and substantia nigra pars reticulata. |
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http://shamimkhaliq.50megs.com/Psychology/Neurotransmitters/parkinsons_disease.htm
(780 words)
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| | Society for Neuroscience News Releases |
| | Another aim of Savasta's work, was to investigate the role of the globus pallidus in mediating the stimulation-induced increase in GABA in the substantia nigra. | | | The goal was to identify the neurochemical changes induced by STN-DBS in the related nuclei of the basal ganglia such as the globus pallidus, a section of the substantia nigra and striatum. | | | In a recent study, Savasta used an in vivo functional approach in rats, by combining the techniques of electrical deep brain stimulation and intracerebral microdialysis (in which minute quantities of fluid are withdrawn from the brain and analyzed). |
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http://www.sfn.org/content/AboutSFN1/NewsReleases/am2002_deep.html
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| | [No title] |
| | The finding of a 27% enlargement in the globus pallidus suggests that this structure should be of particular interest to MRI studies of schizophrenics, especially those, such as first episode studies, looking for the presence of change in volume over time. | | | The strong inverse correlation between the SAPS bizarre behavior score and globus pallidus volume is, nonetheless, interesting, although caution is needed in interpretation because of the small sample and the large number of correlations performed. | | | We thus examined volumes of caudate, putamen and globus pallidus using the latest generation of MRI technology in conjunction with clinical scale and neuropsychological assessment of a group of chronic schizophrenics. |
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http://splweb.bwh.harvard.edu:8000/pages/papers/bg_hokama_95/bg.html
(8078 words)
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| | Team projects on www for Biological Basis of Behavior - 2001 |
| | The putamen is continuous with the caudate nucleus and lies medial to the insula -- bounded laterally by the fibers of the external capsule and medially by the globus pallidus. | | | Recent evidence from studies with nonhuman primates also points to a distinct pallido-thalamo-cortical pathway that may play a cognitive function in which the prefrontal cortex receives inputs from areas of the thalamus that are affected by projections from the internal segment of the globus pallidus (Sadock, p.25). | | | Other areas of the striatum just send their information straight to the internal globus pallidus via inhibitory, GABA-secreting neurons in what is called the "direct pathway" (Sadock, p. |
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http://www.humboldt.edu/~morgan/sub_s01.htm
(4743 words)
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| | Recent Developments in Neuro-surgery for Dystonia – Dr |
| | Three important recent developments in neurosurgery can be observed: 1) the introduction of the globus pallidus as the surgical target structure; 2) the imaging technique of this target structure: and 3) the introduction of continuous deep brain stimulation. | | | However, further studies are necessary to establish factors predicting and determining favourable outcome of pallidal stimulation, such as clinical symptomatology, precise location in the globus pallidus, and stimulation parameters. | | | In general, it appeared that primary generalized dystonia had a better response to this surgery than secondary dystonia. |
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http://www.dystonia-europe.org/europe/Article_Speelman_03.htm
(400 words)
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| | The Neostriatal Mosaic, CR Gerfen, Ann Rev Neurosci 1992 |
| | Consistent with this are the concurrent decrease in 2-deoxyglucose utilization in the external pallido-subthalamic pathway and increased utilization in the internal pallido-thalamic pathway (Mitchell et al 1989). | | | In such studies, specific limb movements are correlated with both decreases and increases in the activity of internal pallidal firing, Such results are suggested to demonstrate that although disinhibitory mechanisms are involved in the generation of specific movements, the opposed mechanism, which results in increased inhibitory processes, may suppress antagonistic movements (Alexander and Crutcher 1990). | | | The generation of eye movements appears to be clearly related to disinhibitory processes whereby pauses in nigrotectal activity are correlated with eye movements (Hikosaka and Wurtz 1983a,b), yet single unit recording studies of internal globus pallidus activity in relationship to limb movements in primates reveals a more complex pattern of activity. |
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http://mickey.utmem.edu/netpapers/Gerfen/Striatum92.html
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| | Context Dependency in the Globus Pallidus Internal Segment During Targeted Arm Movements -- Gdowski et al. 85 (2): 998 ... |
| | Sensory-motor processing in the caudate nucleus and globus pallidus: a single-unit study in behaving primates. | | | Georgopoulos AP, DeLong MR, and Crutcher MD. Relations between parameters of step-tracking movements and single cell discharge in the globus pallidus and subthalamic nucleus of the behaving monkey. | | | Differing theories of globus pallidus (GP) function have emerged from previous studies of behaviorally associated GP neuronal |
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http://jn.physiology.org/cgi/content/full/85/2/998
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| | THALAMOTOMY AND PALLIDOTOMY - Neurosurgical Service - Massachusetts General Hospital |
| | The techniques for microelectrode recording in the globus pallidus have been well described by Lozano et al and Sterio et al.(32, 40) Typically, tungsten microelectrodes with an impedance of 1-2 M Ohm at 1 khz are used. | | | Thus, both pathways ultimately affect the internal segment of the globus pallidus. | | | In the indirect pathway a separate population of striatal neurons first projects to the external segment of the globus pallidus (Figure 2B). |
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http://neurosurgery.mgh.harvard.edu/Functional/pallidt.htm
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| | References |
| | Loher TJ, Hasdemir MG, Burgunder JM, et al: Long-term follow-up study of chronic globus pallidus internus stimulation for posttraumatic hemidystonia. | | | Durif F, Lemaire JJ, Debilly B, et al: Long-term follow-up of globus pallidus chronic stimulation in advanced Parkinson's disease. | | | Kulisevsky J, Lleo A, Gironell A, et al: Bilateral pallidal stimulation for cervical dystonia: dissociated pain and motor improvement. |
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http://www.medscape.com/content/2004/00/48/36/483624/483624_ref.html
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| | Parkinsons Disease Surgery - Detroit, Michigan, Henry Ford |
| | We are currently in the process of determining somatotopic organization of the globus pallidus and internal capsule, whose organization in humans thus far has been only indirectly inferred from the patients with various lesions. | | | Because of the unique features of the microelectrode recording stimulation technique, we are able to map out subcortical structures. |
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http://www.henryfordhealth.org/19269.cfm
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| | [No title] |
| | Neurons projecting from the striatum to the globus pallidus externa (indirect pathway). | | | It excites both the direct and indirect pathways, with preference toward indirect. | | | It secretes dopamine in the striatum, exciting the direct pathway and inhibiting the indirect pathway. |
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http://medicine.creighton.edu/medschool/2006/Review/Neuro/BasalGanglia_a.html
(372 words)
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| | Bibliography: Medtronic & Basal Gang |
| | "The firing pattern of the neurons of the internal Globus Pallidus (GPi) is greatly disturbed in Parkinson's disease. | | | Effect of subthalamic high frequency stimulation on substantia nigra pars reticulata and globus pallidus neurons in normal rats. | | | High-freqency stimulation of the globus pallidus internalis in Parkinson's disease : a study of seven cases. |
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http://www.sm.u-bordeaux2.fr/gross/biblio/bibmedtr.html
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| | Basal ganglia - Wikipedia, the free encyclopedia |
| | Two pathways through the basal ganglia could then be followed. | | | Classic Connectivity Diagram showing glutamatergic pathways as red, dopaminergic as magenta and GABA pathways as blue | | | For example, the internal segment of the globus pallidus in primates is called the entopenduncular nucleus in rodents. |
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http://en.wikipedia.org/wiki/Basal_ganglia
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| | Basal Ganglia and Cerebellum |
| | The relationships between the nuclei of the basal ganglia are by no means completely understood. | | | The anatomy of these structures should be a review from the "coronal and horizontal sections" lab. | | | The SNpc degenerates in Parkinson's disease, but the condition can be treated by giving oral dopamine precursors. |
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http://thalamus.wustl.edu/course/cerebell.html
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| | What is DBS? |
| | Patients bothered by involuntary movements, such as dyskinesia, often experience a marked reduction of these involuntary movements primarily because those patients are able to reduce their medications following surgery. | | | These surgeries are effective but carry significant risks. | | | Deep brain stimulation of the globus pallidus is effective for a wide range of Parkinson's symptoms. |
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http://www.clevelandclinicmeded.com/deepbrainpatient/whatisdbs.htm
(711 words)
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| | Pediatrics: Changes in globus pallidus with (pre)term kernicterus.@ HighBeam Research |
| | We report serial magnetic resonance (MR) and sonographic behavior of globus pallidus in 5 preterm and 3 term infants with kernicterus and describe the clinical context in very low birth weight preterm infants. | | | Pediatrics: Changes in globus pallidus with (pre)term kernicterus.@ HighBeam Research | | | Search for more information on HighBeam Research for. |
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http://www.highbeam.com/library/doc0.asp?DOCID=1G1:111932560&refid=holomed_1
(200 words)
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| | Globus pallidus - Wikipedia, the free encyclopedia |
| | The globus pallidus (Latin for "pale body") is a sub-cortical structure in the brain. | | | The non-primate globus pallidus is usually considered homologous to the primate external segment of the globus pallidus, whereas the non-primate entopeduncular nucleus is often considered the homolog of the internal segment of the globus pallidus. | | | In primates, the medial medullary lamina divides it into two parts—the internal and external segments, which form two of the major nuclei of the basal ganglia. |
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http://en.wikipedia.org/wiki/Globus_pallidus
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| | Quiz4.2001 |
| | d.In the indirect pathway, excitation of the subthalamic nuclei from the association cortex acts on the globus pallidus interna to oppose the inhibition of the caudate/putamen (that is, oppose the direct pathway) | | | Regarding the 'direct' and 'indirect' pathway through the basal ganglia which of the following statements is NOT true. | | | a.In the direct pathway, the globus pallidus interna cells are tonically active and inhibit the VA/VL nucleus of the thalamus. |
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http://socrates.berkeley.edu/~alanburr/neurobio/Neuroexams/Quiz4.2001.html
(531 words)
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| | [No title] |
| | The globus pallidus is the source of efferent pathways from the basal ganglia (caudate, putamen, globus pallidus, amygdaloid, claustrum). | | | Bilateral ablation (surgical removal) of the globus pallidus in animals causes | | | The putamen is lateral to the globus pallidus and contains mostly small neurons with cell bodies in the 10 to 15 micron range. |
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http://kumc.edu/research/medicine/pharmacology/CAI/webCAI/anatomy/ua11.wbc
(497 words)
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| | globus pallidus |
| | Development of responses of globus pallidus and entopeduncular nucleus neurons to stimulation of the caudate nucleus and precruciate cortex. | | | Globus pallidus glial pigment and its changes with age and chronic illness in childhood. | | | Comparison between normal developing striatum and developing striatal grafts using drug-induced Fos expression and neuron-specific enolase immunohistochemistry. |
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http://www.arclab.org/node_pages/2502.html
(606 words)
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| | Deep Brain Stimulation Approved for Parkinson’s Disease |
| | The pivotal study on which the approval was based was published in the September 27, 2001, New England Journal of Medicine. | | | Percent “on” time without dyskinesia increased from 27% to 74% in subthalamic nucleus patients and from 28% to 64% in globus pallidus patients. | | | Percent “off” time decreased from 49% to 19% in subthalamic nucleus stimulation patients and from 37% to 24% in globus pallidus patients. |
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http://www.neurologyreviews.com/apr02/brain.html
(570 words)
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| | [No title] |
| | A. The lenticular fasciculus is comprised of axons of neurons located in the medial globus pallidus. | | | Which is an example of the feedback system in the basal ganglia. | | | All of the following may result in Parkinsonism like symptoms except. |
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http://web.indstate.edu/thcme/anderson/mcbasgl.html
(1086 words)
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| | Evidence for transient perinatal glutamatergic innervation of globus pallidus. |
| | The results suggest that a glutamatergic pathway transiently innervates the globus pallidus during the perinatal period. | | | Because glutamate is an excitotoxin, this pathway may account, in part, for the basal ganglia damage seen in some forms of cerebral palsy after perinatal hypoxia/ischemia. | | | There is no known glutamatergic innervation of globus pallidus (GP) in adult mammals, but we report that during postnatal development of the GP there are large, transient increases in both presynaptic high-affinity glutamate uptake and postsynaptic Na+-independent glutamate receptor binding. |
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http://www.arclab.org/medlineupdates/abstract_2883265.html
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| | Exam 2 |
| | putamen and caudate nucleus Which of the following is an efferent pathway from the globus pallidus? | | | more than one of the above An important basal ganglia feedback circuit is the: Cerebral cortex--Striatum--Globus pallidus-- thalamus--Cerebral Cortex--. | | | C. Medial medullary lamina- fibers that separate the putamen from the globus Pall. |
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http://www.csus.edu/org/nrg/carter/course/bio123/exam/123exam3.htm
(226 words)
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| | Basal Ganglia Disorders |
| | Efferent pathways - major pathway is from globus pallidus to ventrolateral nucleus of the thalamus and then back to cortex | | | Globus pallidus is site or origin for major efferent (output) from basal ganglia | | | Striatum sends output to substantial nigra and globus pallidus |
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http://www.ucs.louisiana.edu/~ncr3025/roussel/codi555/basalganglia.html
(507 words)
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| | [No title] |
| | ^* Neurotransmitters: internal globus pallidus = inhibitory GABA; substantia nigra = GABA Q6=What are major diseases of the basal ganglia and the consequent changes in basal ganglia circuitry and function? | | | A4=* Striatum project to internal and external globus pallidus segments and project to substantia nigra pars reticulata ^* External globus pallidus project to subthalamic nucleus ^* Subthalamic nucleus project to internal globus pallidus Q5=What are the primary efferent structures of the basal ganglia and their neurotransmitters? | | | A3=* Striatum is primary afferent structure ^* Inputs to striatum: neocortex (except primary visual and auditory cortices); substantia nigra pars compacta; and centromedian nucleus of the thalamus ^* Neurotransmitters: neocortex and thalamus = excitatory glutamate; substantia nigra = dopamine (excitatory and inhibitory) Q4=What is the direction of information flow through the basal ganglia? |
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http://www.openwindow.com/ftp/neuro4.fls
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| | Neurotransmitter - June 1995 |
| | Destroying the internal globus pallidus in these monkeys made their parkinsonian symptoms better leading researchers to predict that the same operation should work in humans with Parkinson's disease. | | | If the patient's symptoms get better and if there are no side effects, it is assumed that the electrode is in the internal globus pallidus and the heat is turned on to destroy it. | | | The first is that advances in our understanding of anatomy and physiology led to the prediction that one of the consequences of dopamine cell loss in Parkinson's disease is that nerve cells in the internal segment of the globus pallidus become overactive (See figure). |
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http://dem0nmac.mgh.harvard.edu/newsletter/June1995/pallidotomy.html
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| | Functional Neurosurgery at Massachusetts General Hospital/Harvard |
| | Currently available treatments for movement disorders include microelectrode-guided deep brain stimulation of the subthalamic nucleus, the globus pallidus or the thalamus as appropriate. | | | The center works closely with the Partners Parkinson and Movement Disorders Treatment Center, and the MGH Epilepsy Unit. |
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http://neurosurgery.mgh.harvard.edu/Functional/default.htm
(1135 words)
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| | The Globus Pallidus |
| | Park, M., Falls, W. and Kitai, S. An intracellular HRP study of the rat globus pallidus: I. Responses and light microscope analysis. | | | Although these segments are separated by the medial medullary lamina, the pallidal neurons from each segment are extremely similar, and for the most part morphologically indistinguishable (Carpenter 1981). | | | In nonprimates the anatomical structures usually have a larger separation and are referred to as the pallidum and entopeduncular nucleus (corresponding to the GPe and GPi respectively). |
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http://www.anc.ed.ac.uk/~anaru/research/anatomy/GP.html
(251 words)
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