Download 1. Globus pallidus 2. Subthalamic nucleus 1 2

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1. Globus pallidus
2. Subthalamic nucleus
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Figure 18.5. Functional organization of the outputs from the basal ganglia. (A) Diagram of the targets of the basal
ganglia, including the intermediate relay nuclei (the globus pallidus, internal and external segments, and the
subthalamic nucleus), the superior colliculus, the thalamus, and the cerebral cortex. (B) An idealized coronal
section through the human brain, showing the structures and pathways diagrammed in (A).
Figure 18.10. Summary explanation of
hypokinetic disorders such as Parkinson's
disease and hyperkinetic disorders like
Huntington's disease. In both cases, the
balance of inhibitory signals in the direct and
indirect pathways is altered, leading to a
diminished ability of the basal ganglia to control
the thalamic output to the cortex. (A) In
Parkinson's disease, the inputs provided by the
substantia nigra are diminished (thinner arrow),
making it more difficult to generate the transient
inhibition from the caudate and putamen. The
result of this change in the direct pathway is to
sustain the tonic inhibition from the globus
pallidus (internal segment) to the thalamus,
making thalamic excitation of the motor cortex
less likely (thinner arrow from thalamus to
cortex). (B) In hyperkinetic diseases such as
Huntington's, the projection from the caudate
and putamen to the globus pallidus (external
segment) is diminished (thinner arrow). This
effect increases the tonic inhibition from the
globus pallidus to the subthalamic nucleus
(larger
arrow),
making
the
excitatory
subthalamic nucleus less effective in opposing
the action of the direct pathway (thinner arrow).
Thus, thalamic excitation of the cortex is
increased (larger arrow), leading to greater and
often inappropriate motor activity. (After
DeLong, 1991.)
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A chain of nerve cells
arranged in a disinhibitory
circuit. Top: Diagram of the
connections between two
inhibitory neurons, A and B,
and an excitatory neuron, C.
Bottom: Pattern of the action
potential activity of cells A, B,
and C when A is at rest, and
when neuron A fires
transiently as a result of its
excitatory inputs. Such
circuits are central to the
gating operations of the basal
ganglia.
Hearing loss
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Chemical sensors: Detecting NO in situ
“In vivo nitric oxide sensor using non-conducting polymer-modified carbon fiber.”
Biosensors & Bioelectronics 13 (1998) 1187–1195
nitric
oxide
nitrite
dopamine
ascorbic
acid
“In vivo nitric oxide sensor using non-conducting polymer-modified carbon fiber.”
Biosensors & Bioelectronics 13 (1998) 1187–1195
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Myers et al., “Simultaneous comparison of cerebral dialysis and push-pull perfusion in the brain
of rats: a critical review.”, Neurosci. Biobehav. Rev., 1998, 22, 371-387.
HW#3: Project abstract with references
Due September 25th, 2006, at 7:20pm.
Task: write a 250-350 word abstract describing your project. Include at least two
references. The references do not count toward the word limit.
Grading of this particular homework:
Your classmates will read your abstract, and grade you. So please be clear. Anyone in
the class must be able to understand and report on what you are writing.
Format:
Title.
Author, date.
Abstract:
If you have no idea how to write an abstract, try following this format:
Introduction: describe the problem or the subject in your words.
Methods/results: if you have them. Otherwise describe what other people have done (refer to
bibliography). Compare at least two groups (or two papers).
Conclusion: concisely say again everything you wrote above, but in one or two sentences. You
may also propose a hypothesis to explain the problem described in your project.
References
Write names of authors, title of the paper or book, journal, date, volume, and page
information.
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