Movement Flashcards
Where are alpha motoneurons located in spinal cord?
In anterior horn of spinal cord.
Which types of skeletal muscles do peripheral nerves innervate?
Muscles in trunk/limbs.
Which types of skeletal muscles do cranial nerves innervate?
Muscles in face, trunk and neck.
What is the definition of a tract?
Collect of axons in the central nervous system that has common origin and destination.
What ares types of indirect and direct pathways present?
Direct: -Corticospinal Tract -Corticobulbar Tract Indirect: -Vestibulospinal Tract -Tectospinal Tract -Reticulospinal Tract -Rubrospinal Tract
What is the start, end, nerve type and function of vestibulospinal tract?
Motor Cortex Vestibular Nucleus Vestibulospinal Tract Spinal Cord Peripheral Nerve Skeletal Muscle Function: Head stability (keeps eyes stable as body moves)
What is the start, end, nerve type and function of tectospinal tract?
Motor Cortex Superior Colliculus Tectospinal Tract Spinal Cord Peripheral Nerve Skeletal Muscle Function: Orientation of head towards visual target.
What is the start, end, nerve type and function of reticulospinal tract?
Motor Cortex Reticular Formation Recticulospinal Tract Spinal Cord Peripheral Nerve Skeletal Muscle Function: Maintenance of standing posture
What is the start, end, nerve type and function of rubrospinal tract?
Motor Cortex Red Nucleus Rubrospinal Tract Spinal Cord Peripheral Nerve Skeletal Muscle Function: Unknown
What is the start, end, nerve type and function of corticospinal tract?
Motor Cortex Spinal Cord Peripheral Nerve Skeletal Muscle Function: Goal directed limb movement.
What is the start, end, nerve type and function of corticobulbar tract?
Motor Cortex Brain Stem Cranial Nerve Skeletal Muscle Function: Controls skeletal muscles innervated by cranial nerves.
What is the process of movement, with what relevant brain structures involved?
1) Wanting/deciding to move (prefrontal cortex)
2) Working out where your body is in relation to where you want to move to (primary somatosensory cortex)
3) Planning how you are going to move (premotor cortex & supplementary motor area)
4) Starting to move (substantial nigra and basal ganglia)
5) Commanding skeletal muscle to contract (motor cortex)
6) Skeletal muscle contraction and movement
7) Monitoring, modulation of ongoing movement (cerebellum)
8) Use sensory info to guide movement and determine its success (sensory cortex)
What is function of prefrontal cortex?
Decision making, working memory, planning
What is function of primary somatosensory cortex?
Provides information in limb position
What is function of primary somatosensory cortex?
Provides information in limb position
What is function of premotor cortex?
Visually guided tasks and control and coordination of distal muscles.
What is function of supplementary motor area?
Internally guided tasks and coordination of distal muscles.
What are functions of substantial nigra and basal ganglia?
Selection and initiation of movement.
What is function of motor cortex?
Movement execution, patterns of muscle activity.
What is function of cerebellum?
Monitoring, evaluating, modulating ongoing movement
What brain region plays an important role in motor learning?
Primary Motor Cortex
What does the term neuroplasticity mean?
Structural and/or functional reorganisation can occur with use (motor skill learning) or disuse.
Where does motor learning occur?
Particular neurons in spinal cord, brainstem, cerebellum and primary motor cortex.
What are the cellular mechanisms that underlie neuroplasticity?
- Long term potentiation
- Long term depression
Describe the mechanism of long term potentiation
Occurs when pre-synaptic neuron is stimulating the post-synaptic neuron when the post-synaptic neuron is already strongly depolarised..
HIGH synaptic efficacy.
Describe the mechanism of long term depression
Occurs when pre-synaptic neuron is stimulating pos-synaptic neuron when post-synaptic neuron is already weakly depolarised.
LOW synaptic efficacy.
What does induction of LTP and LTD depend on?
- Frequency of action potential discharge
2. How much simultaneous depolarisation there is in pre/post synaptic neuron
What are the key structures involved in repeating a spoken word?
- Auditory cortex (receives/interpets sound from cochlea)
- Wernicke’s Area (processes sound info into meaningful words)
- Broca’s Area (word based information to activate muscles)
- Primary Motor Cortex (sends movement commands to required muscles).
What are the key structures involved in reading a written word out loud?
- Primary visual cortex (maps of visual field, processes visual info)
- Angular Gyrus (transforms visual info for WA to understand)
- Wernicke’s Area (processes visual info to meaningful words)
- Broca’s Area (converts word-based info to activate muscles)
- Primary motor cortex (sends movement commands to required muscles).
How does control of speech differ to control of movement?
Mechanisms are more complicated, with direct and indirect control of primary motor cortex.
- Checks sound produced matches intended sound
- Corrects mismatch between intended and actual sound
What is the definition of muscle fatigue?
Exercise-induced decline in voluntary force of power.
Describe the central mechanisms of muscle fatigue
Occurring in the nervous system , progressive decline in voluntary activation of muscles.
Describe the peripheral mechanisms of muscle fatigue
Occurring within skeletal muscle fibers, accounts for majority of decline in voluntary force or power.
Describe the sustained isometric maximal voluntary contraction of one muscle group (elbow flexors)
-HIGH: Intramuscular pressure and blood flow. Changes function of skeletal muscles.
Motor neuron firing rates:
-Changes in intrinsic properties of motoneurons.
-Changes in discharge of receptors in skeletal muscle (afferent input).
-High recurrent (Renshaw Cell) inhibition.
-Low stimulation from brain (descending input).
