spch 311 outline 12

direct, voluntary motor system that controls gross motor movement

what is the pyramidal structure?

indirect motor system that controls involuntary movements involved in posture, muscle tone, and reflexes as well as coordination and modulation of movements

what is the extrapyramidal system?

part of the pyramidal tract that runs from cortex to brainstem

- housed entirely in CNS

explain UMN

part of the pyramidal tract that runs from brainstem through cranial or spinal nerves

- housed entirely in PNS

explain LMN

respiration, phonation, resonation, and articulation

4 systems of speech

- we all have thoughts, feelings, and ideas in our head

- when we share these things through speech, we form intention, which involves the entire cerebral cortex with the prefrontal cortex and limbic system playing major roles in process

explain the conceptual level of the motor speech system

linguistic and motor

2 parts of planning level

- non-motor in nature

- taking what we want to express and "dressing" it in language with regard to the meaning we want to express, the grammatical structure with which we want to express it, and the social pragmatic rules we use while expressing it

- the dominant perisylvian region is engaged here

explain linguistic planning

- once phonological assembly has takien place, the motor planning for phoneme production has taken place

- blueprints that are formed when we develop speech and become more defined

- once motor speech for each phoneme is learned, it only needs to be recalled to be executes, rather than be made new each time

explain motor planning

premotor cortex and supplementary motor areas

the __ __ and __ __ __ are important to motor planning

- motor program involved the execution of phonemes in time and space

- takes many motor programs to accomplish a motor plan

- in order to execute proper speech production, the speech organs must move accurately with regard to articulatory target, timing, muscle tone, and force

- sensory feedback involve self correction

explain motor programming level

cerebellum, basal ganglia, and supplementary motor areas

the __, __ __, and __ __ __ are involved at the motor programming level

basal ganglia and cerebellar

2 motor control circuits

coordinating, integrating, and refining movements of the direct and indirect pathways

why are the 2 circuits important to motor programming?

indirect motor system

the basal ganglia circuit is central to the __ __ __

- regulate cortically initiated activity by modifying it

- refine movement by suppressing competing movement that are extraneous to precise and target motor activity

function of basal ganglia nuclei

afferent and efferent loops to join cortical motor areas with thalamus and substantia nigra

the basal ganglia nuclei form what?

regulate muscle tone and posture and to smooth muscle movement

- dampening effect on the cortically initiated motor signals

basal ganglia nuclei use the various neurotransmitters to do what?

dyskinesias as parkinson's

damage to the basal ganglia circuit

automatically incorporates feedback for coordinating skilled, sequential voluntaty muscle activity

the posterior lobe of the cerebellum does what?

cortical motor output to muscles by receiving input from motor cortex, brainstem reticular networks, and the spinal cord

the cerebellum constantly monitors all...

efferent commands regarding the intended movements with the sensory info received from the muscles and joints and coordinates the movement through a motor feedback loop between cerebellum, premotor cortex, and precentral gyrus

the cerebellum compares the....

disdiokinesia - putuhkuh

ataxic dysarthria- sounds drunk, speech slurred

damage to the cerebellar circuit

pyramidal system

the direct motor pathway is also known as __ __

betz cells

- found in 5th layer of cerebral cortex and lateral motor pathways and are found no where else in nervous system

what are the largest of the pyramidal cell and where are they found?

lat corticobulbar, lat corticospinal, and ant corticospinal

3 tracts the pyramidal system involves

lat corticobulbar or lat corticospinal

the betz cell bodies are located in cerebral cortex and their axons course through the __ __ tract or the __ __ tract

to the ventral horn of spinal cord which then synapse directly to muscles

the axons that course through the lat corticospinal tract synapse directly .....

cranial nerve nuclei in the brainstem which go to the muscles those cranial nerves supply

the axons that course through the lat corticobulbar tract synapse with the ....

muscles of the head and neck including those important for speech and swallowing

- controls movement of speech muscles

what does the lat corticobulbar tract control?

basal ganglia and cerebellar circuits; extrapyramidal system

the movement becomes refined through the __ __ and __ __ which are part of the __ __

motor cortex and descend through corona radiata to internal capsule to brainstem where they cross at medulla and spinal cord juncture

where do the tracts of the pyramidal system begin?

it leaves the brainstem as a cranial nerve and directly innervates various muscles in head and neck

in the case of the lat corticobulbar tract, once it crosses the medulla, ....

result in spastic muscles due to overactive muscle tone (hypertone) and overactive reflexes (hyperreflexia)

damage to UMN

- results in flaccid muscles due to lack of muscle tone (hypotonia) and lack of reflexes (hyporeflexia)

damage to LMN

LMN damage in which spontaneous depolarization of LMN occur resulting in contraction of individual muscle fibers but not all of them within a muscle

explain fasciculations

slurred, uncoordinated speech due to CNS or PNS problems affecting one or more of the processes of speech

what is dysarthria?

- result from UMN damage

- stiff and rigid muscles

what is spastic dysarthria?

strained/strangled, harsh voice, monopitch, hypernasal, slow speech rate, and imprecise consonant production

characteristics of spastic dysarthria

LMN damage

what is flaccid dysarthria from?

breathy voice quality, monopitch, hypernasality, imprecise consonant production and short phrases

characteristics of flaccid dysarthria

- extrapyramidal system

- controls involuntary movements involved in posture, muscle tone, and reflexes as well as coordination or modulation of movements

what is the indirect motor system?

corticoreticular-input into rf

corticobulbar-input into midbrain

2 tracts in extrapyramidal

rubrospinal, vestibulospinal, reticulospinal, and tectospinal

4 tracts that originate in brainstem and input in various places along spinal cord

basal ganglia, cerebellum, and thalamus

the tracts of extrapyramidal make many stops which include the __ __, __, and ___ before getting to final destination at the brainstem or spinal cord

loss of coordination and modulation, leading to dyskinesias

- tremors, chorea, dystonia, and clonus

damage to extrapyramadal system results in:

tremors

rhythmic shaking

chorea

quick movements of the hands and feet

athetosis

slow, writhing movements

dystonia

distorted posture

clonus

large muscle contractions

hyperkinetic and hypokinetic dysarthria

2 speech problems involved in extrapyramadal system

- too much movement caused by basal ganglia damage

- speech is characterized by harsh voice, monopitch, loud voice level, and imprecise consonants and distorted vowels

what is hyperkinetic dysarthria?

- related to too little dopamine production in substantia nigra

- parkinson's is characterized by low levels of dopamine

what is hypokinetic dysarthria?

breathy voice, monopitch, reduced syllable stress, variable speech rate, and imprecise consonants

hypokinetic dysarthria demonstrates what ?

extrafusal and intrafusal

2 fibers of the skeletal muscles

extrafusal muscle fibers

which fibers are innervated by alpha motor neurons (LMN) that contract fibers facilitating movement?

intrafusal muscle fibers

which fibers are innervated by gamma motor neurons which are involved in proprioception and influenced by extrapyramidal system?

alpha motor neuron

an __ __ __ divides into many branches as it travels to a muscle

tone

the degree of contraction in any given muscle

by how many muscle fibers are contracted at any given moment

how is tone determined?

tetany

too much tone

flaccidity

too little tone