Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
25 Cards in this Set
- Front
- Back
|
Name the three complex processes of simple voluntary movement.
|
1. Identification and localization of targets.
2. Planning the movement 3. Executing |
|
|
The cortical motor areas are capable of influencing motor behavior both ________ through the brainstem and ________ by corticospinal projections.
|
1. indirectly
2. directly |
|
|
T/F - The corticospinal tract is the largest descending fiber tract in the brain.
|
True
|
|
|
Lateral corticospinal tract neurons terminate in the _______ part of the ventral horn while the ventral corticospinal tract terminates bilaterally in the __________ cell column which contains neurons controlling _________ musculature.
|
1. dorsolateral
2. ventromedial 3. axial |
|
|
Some lateral corticospinal fibers produce monosynaptic excitation of ____ and ____ motorrneurons that innervate distal _____ muscles.
|
1. alpha
2. gamma 3. flexor |
|
|
Most corticospinal fibers synapse on and (excite or inhibit) either excitatory or inhibitory interneurons.
|
excite
|
|
|
Some corticospinal axons synapse in the ____ nucleus as a way to modulate muscle movement.
|
Red nucleus
|
|
|
By electrical stimulation the primary motor cortex can cause contrations around (single or multiple) joints?
Supplementary or premotor cortex? Direct stimulation of the supplementary cortex cause _____ limb movement. |
1. single
2. multiple 3. bilateral |
|
|
The main role of the corticospinal tract neurons is to enable control of what?
|
Distal finger musculature
|
|
|
The supplementary motor and premotor corticies act on distal muscles through what?
|
Projections to the primary motor cortex
|
|
|
The most common type of damage in the motor cortex areas results from what?
|
Strokes
|
|
|
What are negative signs on physical exam?
Positive signs? |
Negative signs --> loss of function
Ex. paresis, paralysis Positive signs --> gain of function Ex. hyper-reflexia, Babinski reflex |
|
|
Damage to the corticospinal tract in primary results in profound loss in the ability to do what?
What muscle control is preserved? |
Use the wrist and fingers independently to manipulate objects.
Axial musculature is unaffected and they can maintain posture, walk, and climb without difficulty |
|
|
T/F -- firing of primary cortex neurons beings before the movement onset.
|
True
|
|
|
The firing rate of primary cortex neurons encodes what to muscles?
|
Amount of force -- even for the same motion, a neuron will fire more if more force is requires to execute the movement.
|
|
|
1. T/F - Different neurons fire in relation to different directions of movement.
2. From experiments that determined the property described above, how were neurons characterized? |
1. True -- primary motor cortex neurons fire for movements in a preferred direction and not fire for movements in other directions
2. "tuned" quite broadly |
|
|
What is a motor neuron population vector? What is it a good predictor of?
|
The direction of movement that is determined by the vectorial sum of a population of motor neurons.
2. The actual direction of movement that population of neurons controls. |
|
|
Which motor cortex is involved is active in simple finger flexing?
|
primary motor cortex
|
|
|
Which motor cortex is involved is active in complex finger movement?
|
Primary and supplementary motor cortex
|
|
|
Which motor cortex is involved is active in mental rehearsal of complex finger movements?
|
Supplementary motor area
|
|
|
The premotor area is involved with what?
|
Planning complex movements
|
|
|
Increasing motor skill does what to the primary motor cortex?
|
Expands the representation of the learned movement in the cortex
|
|
|
What initiates "slow" processes that result in large changes in motor performance over a few weeks?
|
Brief, daily training epochs
|
|
|
What processes results in significant reorganization in the movement representation within the primary motor cortex?
|
Acquisition and retention of motor skill
|
|
|
What does rehabilitative training do for victims of small strokes?
|
improves the loss of digit representation in the primary motor cortex
|
