Ch.7 Flashcards
what do axons travel through to get to the spinal cord
corticospinal tracts
how many separate tracts does the corticospinal tract have?
2
what info does the lateral corticospinal tract send
sends info to arms and legs
what info does the anterior/ventral corticospinal tract send
sends info to trunk, control the muscles of the core or midline of the body
what are upper motor neurons
bundles of axons that extend from the cell bodies in the motor cortex found along the corticospinal tract
where are lower motor neurons found
gray matter of the spinal cord
how many nerves are in the spinal cord?
31
what does the spinal cord do?
sends signals to and from the body
what info is processed by the dorsal root?
afferent sensory info
what info is processed by the ventral root?
efferent motor info
what do interneurons do?
connect the dorsal root (sensation) to the lower motor neurons
what is the reflex arc
occurs when someone touches something hot
how does the reflex arc get processed by nuerons
sensory neuron -> interneuron -> lower motor neuron
what are the 3 types of muscles
cardiac, smooth, and skeletal
where is cardiac muscle located
heart
where is smooth muscle located
organs
biofeedback
looks at how we may be able to control more movement than we typically do such as holding breath
what two types of fibers make of the skeletal muscle
extrafusal and intrafusal
what are extrafusal fibers
muscle cells that contract to shorten a muscle
what are intrafusal fibers
-muscle cells that detect changes in muscle length
-sensory receptors monitor stretching
what is the neuromuscular junction
the synapse formed when the axon terminal of a motor neuron positions itself in a section of the extrafusal muscle fiber known as the motor end plate
what is the motor end plate
an area that is highly excitable and appropriate for the initiation of action potentials
what are antagonistic muscles
produce actions that are opposite of one another for example biceps and triceps enable the arm to move toward and away from the body
proprioception
ability to sense the position, orientation, and movement of ones own body
what does the golgi tendon organ do?
when a muscle contract excessively it sends a message back to the nervous system to initate the appropriate compensatory action
what does the supplementary motor complex do
helps guide the execution of complex behvaior
what makes up the supplementary motor complex?
supplementary motor area (SMA) and presupplementary motor area (pre-SMA)
when is SMA activated?
when we think about doing soemthing
when is preSMA activated
when we actually do something
what leads to diminished activation of SMA and pre SMA
proficiency at task
what do cortical areas (SMA, pre-SMA, premotor cortex) play a key role in
voluntary movements
what is the basal ganglia and what are its primary components
-collection of interconnected nuclei that surround the thalamus and regulate movement
-consists of caudate nucleus, putamen, globus pallidus
what do the 3 structures of the basal ganglia communicate with
substantia nigra
what makes up the striatum
caudate and putamen
what is the role of the basal ganglia
-Creates a motor loop in which these structures put together info from the cortical areas and send it to the cortex for movement execution, involved with motor regulation
-also involved with learning and habit formation, attention, rewarded behaviors, and emotional responses
how much of the brains volume is made up of the cerebellum
10%
what is the last stop in the brain for movement
cerebellum
what is the function of the flocculondular lobe in the cerebellum
balance and posture
what is the function of the Vermis and lateral cerebellar hemispheres in the cerebellum
regulate muscle tone
what is the function of the cerebella peduncles in the cerebellum
communication with other brain regions
what is the role of the cerebellum
movement, coordination, balance, and muscle tone
Cerebellar cognitive affective syndrome affects what
Executive function, language, sequencing events, visuospatial abilities are all affected
What does it take to become an expert in motion
-10,000 hours of distributed practice
-Intentional repetitive practicing of skills
-10 years
-trial and error
what is automaticity in the context of expertise and motion
less attention needed to perform a certain action
what is efficiency in the context of expertise and motion
less neural activation is required to do well
benefits of exercise
-improves intelligence scores
-prevents cognitive decline
-enhances learning
What is Parkinson’s disease and who does it typically affect
-neurodegenerative disease
-often found in older adults
what physical changes occur in result of Parkinson’s disease
-akinesia (lack of voluntary movement)
-muscle tremors (shaking at rest)
-rigidity of movement
-fewer automatic movements
what is akinesia
lack of voluntary movements often seen in those with Parkinson’s disease
what happens to the substantia nigra in Parkinson’s disease
degeneration of neurons accompanied by decreased levels of dopamine
what are lewy bodies
protein deposits present in the cell body in brain areas affected by Parkinson’s
what is L-DOPA used for
offers temporary relief of symptoms associated with Parkinsons disease but becomes less effective over time
how can surgery be used to treat Parkinsons disease
-Transplanting dopaminergic neurons to substantia nigra (variable success rates)
-Lesioning the basal ganglia
what does lesioning the basal ganglia do for those with Parkinsons
-decrease termor
-Blocks habitual motor messages that compete with goal directed movement
what is paraplegia
inability to move lower extremities
what is quadriplegia
inability to move lower, upper extremities and torso
treatments for movement disorders
-transplants can lead to some regeneration
what are autologous transplants
your own cultured tissue
what is neurorehabilitation
stimulation/agonist drugs/harness training
robotic control
electrode implants in motor cortex
