Term
What occurs with classic conditioning? |
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Definition
When a weak stimulus (conditioned stimulus) that normally does not elicit a response is paired with a strong stimulus (unconditioned stimulus) that always elicits a response. |
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Term
What deficits occur with cerebellar patients? |
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Definition
inability to acquire conditioned eye blink responses however, retainement of previously learned eye blink responses. |
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Term
What occurs with saccade adaptations? |
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Definition
The visual system is tricked by changing the target position as eye movement occurs, reducing the effective number of saccades needed. After subsequent trials, saccades produced are simply higher in amplitude and fewer in frequency. The brain learns ! |
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Term
What deficits occur with cerebellar lesions? |
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Definition
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Term
Describe this graph:[image] |
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Definition
The prism alters the perception of visual stimuli. The adjustment occurs at both visual and proprioreceptive levels. After the prism is removed, there is a negative aftereffect. |
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Term
How do we know that the adjustment is visual and proprioreceptive? |
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Definition
-If it only affected the visual region, then both hands would be affected. -If it was purely proprioreceptive, then an afteraffect would occur in any motor output generated in the arm used during exposure. (NOT THE CASE) |
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Term
What areas of the brain are involved with the Prism Adaptation? |
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Definition
Cerebellum, Posterior Parietal Cortex and Pre-Motor Cortex. |
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Term
How do cells respond with or without visual feedback? |
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Definition
Visually-responsive cells respond differently depending on whether arm is visible during movement. |
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Term
What does the impairment of Pre-Motor Cortex result in? |
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Definition
Disfunction of visually guided tasks ( not internally generated tasks) |
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Term
What does the cerebellum code for in regards to the Prism Adaptation? |
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Definition
visual tracking, and visually guided movements! |
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Term
What occurs with a cerebellar lesion patient? |
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Definition
Subjects have difficulty in pointing at stationary targets or following moving targets. TRACKING OBJECTS |
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Term
What does Parkinson's Disease affect? |
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Definition
Degenerative disease affecting the Substantia Nigra Pars Reticula and it's dopamine producing cells. |
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Term
Define the Excitotoxicity of Parkinson's disease |
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Definition
The metabolization of hydrogen peroxide is normally broken down by glutathione. In Parkinson's disease there is a decrease in Glutathione levels in the substantia nigra, which leads to a build up of hydrogen peroxide and free radicals leading to cell death. |
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Term
What are the effects of Parkinson's Disease? |
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Definition
An imbalance in the excitatory and inhibitory inputs to the thalamus. Too little input from the excitatory Substantia Nigra, and too much inhibitory input from Putamen. |
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Term
What are the symptoms of Parkinson's disease? |
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Definition
T-tremor, occurs during resting and typically in hands R- rigidity, or stiffness of joints A- akinesia, or difficulty to initiate movements. P-postural imbalances, or instable gait
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Term
What is the difference between patients with cerebellar lesions and patients with Parkinson's. |
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Definition
Tremors occur at rest during parkinson's disease, while tremors occur during movement with cerebellar lesions. |
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Term
Why do parkinson's patients use both agonist/antagonist muscle groups during postural perturbation trials? |
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Definition
They have an inability to adjust postural control to specific contexts, and therefore use the most complex adjustments no matter the context. |
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Term
What are some possible techniques to repair Parkinson's disease. |
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Definition
-L-Dopa -Transplantation of dopamine reducing cells -Neurosurgically to repair imbalances of imputs to thalamus by lesioning/stimulating specific cites in the basal ganglia. |
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