speech pathways & Cranial nerves intro Flashcards
Motor unit consists of:
motor neuron and muscle fibers innervated by the motor neuron
______ ______motor neuron and muscle fibers innervated by the motor neuron
Motor unit
Motor neurons are nerve cells involved in _____ _____ & originate in _____ or _____ from a cranial or spinal nerve.
motor movement
brainstem
spinal cord
motor neurons that involved in motor movement & originate in brainstem and spinal cord from a cranial or spinal nerve are also called _____ _____ _____.
lower motor neurons
______ of these neurons leave cell bodies & travel to specific muscles. _____subdivide into branches that connect with muscle fibers.
Axons
An axon splits into branches, thus can ______ several miscle fibers. Also each fiber may receive input from branches of _____ motor neurons.
innervate
different
Without proper _____ muscle _______. May also result in ________.
innervation
atrophies
fasciculations
Upper motor neurons are
cell bodies in motor cortex and their descending processes that synapse on cranial and spinal motor neurons
_______ _______ ______ are cell bodies in motor cortex and their descending processes that synapse on cranial and spinal motor neurons
Upper motor neurons
Lower motor neurons are :
motor nuclei through which central nervous system sends impulses to muscles (and glands)
______ _____ _____ are motor nuclei through which central nervous system sends impulses to muscles (and glands)
Lower motor neurons
UMN originate in:
upper brain levels
LMN originate in:
brainstem and spinal cord
What are the 4 main parts to speech motor system
- Final common pathway
- Direct activational pathway
- Indirect activational pathway
- control circuits
Speech motor system emphasizes _____ or ______ pathways, however ______ or _____ pathways are important also and problems in _____ pathways can impact motor function,
motor or efferent
afferent or sensory
sensory
Final common pathway is also called?
Lower motor neuron system
Final common pathway:
It’s the last link in sequence of motor events that lead to motor movement & all other components have to go through it.
The _____ _____ _____ is the last link in sequence of motor events that lead to motor movement & all other components have to go through it.
Final common pathway
The final commont pathway has __ paired cranial nerves and ___ paired spinal nerves.
12
31
______ innervation receives innervation from both sides. protective function for most cranial nerves. If one side is damaged, the other sides may stay intact. provides protection for important functions.
Bilateral
bilateral innervation:
receives innervation from both sides. protective function for most cranial nerves. If one side is damaged, the other sides may stay intact. provides protection for important functions.
Unilateral innervation:
receives innervation from only 1 side so damage occurs more easily.
_______ innervation receives innervation from only 1 side so damage occurs more easily.
Unilateral
________ innervation receives innervation from opposite side.
Contralateral