muscle control Flashcards
most visceral reflexes for the organs have a ____ firing rate
tonic
brain region involved in activating alpha motor neurons and motor units
primary motor cortex
brain region involved in making appropriate movement and aids in motor memory
premotor cortex
brain region involved in complex and sequential movements
supplementary motor cortex
brain region involved in inhibiting unwanted movements; has influence on pre and primary motor cortex
association cortex: prefrontal cortex
brain region involved in motivated movement by dopamine and tells brain what to do
basal ganglia and substantia nigra
brain region involved in movement modification to make them more precise and accurate; maintains posture
cerebellum
what is true of the alpha motor neurons
a. develop force
b. initiate in the dorsal horn
c. exit CNS via spinal cord
d. all of the above
a
what is not true of muscle spindles
a. provide sensory feedback
b. contain a connective tissue capsule
c. contain intrafusal fibers inside the muscle spindle
d. have a phasic firing rate
d
the muscle spindle reflex is a ____ ____ loop
negative feedback
what is true of the stretch receptor reflex without gamma activation
a. the intrafusal fibers wil contract
b. the extrafusal fibers will stop contracting when the stretch has reached potential
c. the muscle spindle becomes compressed and can no longer send stimulus about stretch
d. no damage to the muscle will occur
c
what reflex is receptive to tension in the tendons and responds primarily to isometric phase of voluntary muscle contraction
golgi tendon organs
which reflex develops allows better motor control and posture due to sensory communication
a. golgi tendon
b. muscle spindle
golgi tendon
which reflex develops passive force and maintains appropriate muscle tension
a. golgi tendon
b. muscle spindle
b
corticospinal pathways are always ____lateral
contra
what is true of the lateral corticospinal pathway?
a. 80-90% of pyramidal fibers
b. decussates in the spinal cord
c. innervates axial skeleton
d. all of the above
a.
decussates in the medulla
innervates distal limbs
what is true of the anterior coticospinal pathway?
a. 10-20% pyramidal fibers
b. decussates at level of synapse in spinal cord
c. innervates axial skeleton
d. all of the above
d
what is not true of the corticobulbar tracts?
a. not always contralateral
b. has many areas of decussation
c. pathway does not innervate the cranial nerves
c
the corticoculbar and corticospinal pathways are
a. voluntary
b. involuntary
c. ipsilateral
d. A and C
a
the brainstem pathway is ____ and _____
involuntary and ipsilateral
what is not true of the brainstem pathway?
a. does not decussate
b. starts in cortex
c. innervates muscle of the trunk
d. does balance, posture, and central pattern generators
b
hypertonia is usually an issue of the ____ motor neuron
upper (upper alpha motor nueron)
what disease is characterized by basal nuclei dysfunction that result in bradykinesia in voluntary movements; symptoms are tremors at rest and shuffling gate (
parkinsons disease
parkinsons is a result of degredation of ___ ____ and lowered dopamine release to basal ganglia
substantia nigra
what disease is characterized by undesired tremors and lack of coordinated movements; difficulty learning new movements
cerebellar ataxia
what disease is characterized by poor muscle tone, muscle imbalance and other brain development problems such as epilepsy
cerebral palsy (caused by reduced blood flow early in development)
