SPLH 620 ALL 2027 EXAM SCRIPT ANSWERS AND
QUESTIONS SET A+
✔✔What is the definition of the speech motor system? - ✔✔—A complex network of
structures and
pathways that organize, control and execute voluntary movements.
—Resides at all levels of the NS.
✔✔What are the steps/model of speech motor control? - ✔✔1. Auditory cortex
2. Prefrontal cortex
3. Broca's area
4. Premotor and supplementary motor areas
5. Basal ganglia (excite or inhibit action)
6. Primary motor cortex
7. Corticobulbar/Corticospinal tracts to relevant muscles
8. Cerebellum (copy is sent there)
✔✔What are some of the characteristics of the primary motor cortex? - ✔✔1. Important
for execution.
2. Provides most of the descending projection into the brainstem and spinal cord.
3. Electrical stimulation leads to contraction of
individual muscles (not coordinated movements);
4. Lesions leads to contralateral weakness to body part mapped to lesioned site.
5. Somatotopically organized (spatial organization by region of the body)
✔✔What are some of the characteristics of the premotor cortex and supplementary? -
✔✔1. Planning and co-ordination of complex
movements.
2. Most of output goes to M1.
3. Imaging studies show activity in these regions when people execute a sequence of
movements - or when they imagine them
4. Receive input from association areas of
the parietal and temporal cortex. (MOTOR PLANNING/PROGRAMMING!!!)
,✔✔Broca's aphasia characteristics? - ✔✔- speech nonfluent
- comprehension better
than production
✔✔What is involved in the pyramidal system/tract? - ✔✔= direct activation pathway,
direct
motor system
• Controls voluntary movements
(finely controlled, skilled, discrete, rapid)
• Has only one axonal synapse
• Innervates LMNs (IPSILATERAL??)
✔✔What is involved in the extrapyramidal system/tract? - ✔✔= indirect activation
pathway, indirect motor system, brainstem motor pathways
• Provides framework on which skilled actions can be accomplished, controls posture
and tone, regulate reflexes (involuntary)
• Source of input to LMNs via multiple synapses
• Smaller, short, local, circuits
✔✔What are the disorders of the motor system that affect speech? Conceptualization, •
Linguistic planning, • Motor planning or programming, • Motor execution, • Sensory
feedback? - ✔✔• Cognitive/intellectual impairment (e.g., dementia)
• Aphasia
• Apraxia of speech
• Dysarthria
• Dysarthria and peripheral sensory-based speech disturbances
✔✔Where are the localizations for spastic and flaccid dysarthria? What about
hypokinetic and hyperkinetic dysarthria? - ✔✔F: LMN (cranial nerves)
S: UMN (Prim Motor cortex, Corticobulbar tract)
Hypo & Hyper: Basal ganglia
✔✔What is apraxia of speech and its characteristics? - ✔✔AOS: Disorder of speech
motor planning (loss of the ability to carry out learned purposeful movements)
• Almost always caused by lesions in the languagedominant (usually left) hemisphere of
the brain. "Speech doesn't come out right" Mispronunciation, Nonfluent, Inconsistent
errors, Speak slowly to prevent errors
✔✔What is Dysarthria and its characteristics? - ✔✔Poor control of the speech
articulators (Jaw, lips, tongue).
, F: decreased muscle tone, decreased reflexes, Fasciculation, fibrillations, Atrophy
S: Increased muscle tone (spasticity), increased reflexes, clonus
✔✔What would happen if there was a unilateral LMN or UMN lesion on CN V? What
about a bilateral lesion? - ✔✔Unilateral LMN lesion
• Affects one side of jaw but
can still move jaw, no major effects on speech.
Unilateral UMN lesion
• No effect on speech
Bilateral LMN/UMN lesion
• jaw hangs open, cannot be
closed, movement with
limited range
• Affects articulation
✔✔Study the examples of different areas for lesions from class! - ✔✔STUDY!
✔✔CN VII effects on speech? Unilateral LMN and bilateral LMN & UMN? - ✔✔Unilateral
LMN: effect more visual than auditory
Bilateral UMN & LMN: inability to produce /b, p, w, f, v/, vowels are distorted
✔✔What would happen if there was a lesion on the CN IX nerve? - ✔✔• CN IX is rarely
damaged in isolation
• CN IX role on speech cannot be assessed directly. It probably has some influence on
resonance and phonatory functions because of effects of lesion on pharyngeal
elevation.
✔✔What would happen if there was a lesion on the unilateral or bilateral LMN of the CN
X nerve? - ✔✔Unilateral:
• Hoarseness (due to paralysis of the ipsilateral intrinsic muscles of the larynx).
Bilateral:
• Devastating effects on phonation, resonance, and swallowing with significant effects
on prosody and clarity of articulation
✔✔What would happen if there was unilateral or bilateral LMN lesion on CN XI? -
✔✔Sternocleidomastoid, trapezius
• Generally unilateral LMN lesion to CN XI does not affect speech.
• Bilateral LMN weakness: cause postural weakness which can affect respiration,
phonation, resonance indirectly
✔✔What would happen if there was unilateral or bilateral LMN lesion on CN XII? -
✔✔(Innervates all intrinsic and all but one extrinsic muscles of the tongue)
• Unilateral LMN lesion: leads to tongue deviation to side of lesion on protrusion
• Bilateral LMN lesion? Severe articulation problems.
QUESTIONS SET A+
✔✔What is the definition of the speech motor system? - ✔✔—A complex network of
structures and
pathways that organize, control and execute voluntary movements.
—Resides at all levels of the NS.
✔✔What are the steps/model of speech motor control? - ✔✔1. Auditory cortex
2. Prefrontal cortex
3. Broca's area
4. Premotor and supplementary motor areas
5. Basal ganglia (excite or inhibit action)
6. Primary motor cortex
7. Corticobulbar/Corticospinal tracts to relevant muscles
8. Cerebellum (copy is sent there)
✔✔What are some of the characteristics of the primary motor cortex? - ✔✔1. Important
for execution.
2. Provides most of the descending projection into the brainstem and spinal cord.
3. Electrical stimulation leads to contraction of
individual muscles (not coordinated movements);
4. Lesions leads to contralateral weakness to body part mapped to lesioned site.
5. Somatotopically organized (spatial organization by region of the body)
✔✔What are some of the characteristics of the premotor cortex and supplementary? -
✔✔1. Planning and co-ordination of complex
movements.
2. Most of output goes to M1.
3. Imaging studies show activity in these regions when people execute a sequence of
movements - or when they imagine them
4. Receive input from association areas of
the parietal and temporal cortex. (MOTOR PLANNING/PROGRAMMING!!!)
,✔✔Broca's aphasia characteristics? - ✔✔- speech nonfluent
- comprehension better
than production
✔✔What is involved in the pyramidal system/tract? - ✔✔= direct activation pathway,
direct
motor system
• Controls voluntary movements
(finely controlled, skilled, discrete, rapid)
• Has only one axonal synapse
• Innervates LMNs (IPSILATERAL??)
✔✔What is involved in the extrapyramidal system/tract? - ✔✔= indirect activation
pathway, indirect motor system, brainstem motor pathways
• Provides framework on which skilled actions can be accomplished, controls posture
and tone, regulate reflexes (involuntary)
• Source of input to LMNs via multiple synapses
• Smaller, short, local, circuits
✔✔What are the disorders of the motor system that affect speech? Conceptualization, •
Linguistic planning, • Motor planning or programming, • Motor execution, • Sensory
feedback? - ✔✔• Cognitive/intellectual impairment (e.g., dementia)
• Aphasia
• Apraxia of speech
• Dysarthria
• Dysarthria and peripheral sensory-based speech disturbances
✔✔Where are the localizations for spastic and flaccid dysarthria? What about
hypokinetic and hyperkinetic dysarthria? - ✔✔F: LMN (cranial nerves)
S: UMN (Prim Motor cortex, Corticobulbar tract)
Hypo & Hyper: Basal ganglia
✔✔What is apraxia of speech and its characteristics? - ✔✔AOS: Disorder of speech
motor planning (loss of the ability to carry out learned purposeful movements)
• Almost always caused by lesions in the languagedominant (usually left) hemisphere of
the brain. "Speech doesn't come out right" Mispronunciation, Nonfluent, Inconsistent
errors, Speak slowly to prevent errors
✔✔What is Dysarthria and its characteristics? - ✔✔Poor control of the speech
articulators (Jaw, lips, tongue).
, F: decreased muscle tone, decreased reflexes, Fasciculation, fibrillations, Atrophy
S: Increased muscle tone (spasticity), increased reflexes, clonus
✔✔What would happen if there was a unilateral LMN or UMN lesion on CN V? What
about a bilateral lesion? - ✔✔Unilateral LMN lesion
• Affects one side of jaw but
can still move jaw, no major effects on speech.
Unilateral UMN lesion
• No effect on speech
Bilateral LMN/UMN lesion
• jaw hangs open, cannot be
closed, movement with
limited range
• Affects articulation
✔✔Study the examples of different areas for lesions from class! - ✔✔STUDY!
✔✔CN VII effects on speech? Unilateral LMN and bilateral LMN & UMN? - ✔✔Unilateral
LMN: effect more visual than auditory
Bilateral UMN & LMN: inability to produce /b, p, w, f, v/, vowels are distorted
✔✔What would happen if there was a lesion on the CN IX nerve? - ✔✔• CN IX is rarely
damaged in isolation
• CN IX role on speech cannot be assessed directly. It probably has some influence on
resonance and phonatory functions because of effects of lesion on pharyngeal
elevation.
✔✔What would happen if there was a lesion on the unilateral or bilateral LMN of the CN
X nerve? - ✔✔Unilateral:
• Hoarseness (due to paralysis of the ipsilateral intrinsic muscles of the larynx).
Bilateral:
• Devastating effects on phonation, resonance, and swallowing with significant effects
on prosody and clarity of articulation
✔✔What would happen if there was unilateral or bilateral LMN lesion on CN XI? -
✔✔Sternocleidomastoid, trapezius
• Generally unilateral LMN lesion to CN XI does not affect speech.
• Bilateral LMN weakness: cause postural weakness which can affect respiration,
phonation, resonance indirectly
✔✔What would happen if there was unilateral or bilateral LMN lesion on CN XII? -
✔✔(Innervates all intrinsic and all but one extrinsic muscles of the tongue)
• Unilateral LMN lesion: leads to tongue deviation to side of lesion on protrusion
• Bilateral LMN lesion? Severe articulation problems.
