Apraxia of Speech

Question 1

Apraxia Defined

Answer 1

motor speech disorder “resulting from impairment, as a result of brain damage, of the capacity to program the positioning of speech musculature and the sequencing of muscle movements for the volitional production of phonemes

Question 2

Apraxia

Answer 2

no significant weakness, slowness, or incoordination in reflex or automatic acts

prosodic alterations may be associated with the articulatory problem, perhaps in attempts to compensate

Question 3

AOS Overview

Answer 3

• neurological deficit in the production of speech sounds
• occurs in the absence of muscle weakness, abnormal muscle tone, reduced ROM, or decreased muscle steadiness
• a deficiency in the ability to accurately sequence the movements needed to produce speech sounds
• probably should be referenced as dyspraxia as there is “disordered action” not a lack of movement

Question 4

AOS Types

Answer 4

1. ideational apraxia

2. ideomotor apraxia

Question 5

Ideational Apraxia

Answer 5

• inability to make use of an object or gesture because the individual has lost the knowledge (or idea) of the object’s or gesture’s function
• disturbance in the conception of an object/gesture
• uncommon disorder that typically results from damage to the left parietal lobe
• often goes undetected masked by other disorders (i.e., aphasia)
• difficult to detect as it resolves quickly when caused by a stroke

Question 6

Ideomotor Apraxia

Answer 6

• disturbance in the performance of the movements needed to use an object, make a gesture, or complete a sequence of individual movements
• AOS is one of the ideomotor apraxias
• typically affects the voluntary movements more so than the automatic movements

Question 7

3 Subcategories of Ideomotor Apraxia

Answer 7

1. Limb Apraxia
2. Nonverbal Oral Apraxia
3. AOS

Question 8

Limb Apraxia

Answer 8

• inability to sequence the movements of the arms, legs, hands, or feet during a volitional action
• often results from left hemisphere damage

-affects both the right/left limbs, although
hemiplegia may hide its effects on one side of the body

Question 9

Nonverbal Oral Apraxia

Answer 9

aka: oral apraxia, buccofacial apraxia, facial apraxia or lingual apraxia
- deficit in the ability to sequence nonverbal voluntary movements of the tongue, lips, jaw, and other associated oral structures
- individuals will grope for the correct position, delay performing the action, add extra unnecessary movements
- commonly seen in those suffering left hemisphere damage; can co-occur with aphasia
- can co-occur with AOS or verbal apraxia of speech

Question 10

AOS

Answer 10

• deficit in the ability to sequence the motor commands needed to correctly position the articulators during voluntary production of phonemes
• usually caused by damage to the left frontal lobe, especially when damage occurs near Broca’s area

Duffy suggests it can co-occur with UUMN dysarthria

Question 11

AOS Etiologies

Answer 11

AOS is typically the result of injury to the perisylvian area of the left hemisphere of the brain

Injuries to the insula and the basal ganglia have also been know to cause AOS

Specific etiologies: CVA, degenerative disease, trauma, tumor

• most common is CVA (58%)
• degenerative disease: Alzheimer’s, PPA, Creutzfeldt-Jakob disease (16%)
• trauma (15%); typically surgical trauma
• (11%) were tumor related

Question 12

Speech Characteristics of AOS

Answer 12

AOS is primarily a disorder of articulation and prosody

The other sub-systems may be impacted as well

Question 13

AOS Articulation

Answer 13

• substitutions of one phoneme for another are more common (may be distortions of the target phoneme though)
• placement errors are the most frequent type of substitution error followed by manner, voicing, and oral-nasal errors
• substitution of a voiceless phoneme for a voiced phoneme is more common
• fricatives and affricates are more often in error than stops, nasals, semivowels or vowels
• consonant clusters are more likely to be in error

Question 14

AOS Articulation Cont…

Answer 14

• initial position deficits are more likely than medial or final consonant positions
• articulation is more accurate on real words than on nonsensical words
• errors are more common on multisyllabic words

-the > the distance b/w articulatory contacts the higher the rate of b/d
“puh, puh, puh” vs. “puh, tuh, kuh”; think about AMRs vs. SMRs

-errors will be inconsistent during repeated utterances of the same word

Question 15

AOS Prosody

Answer 15

[1] rate of connected speech is slower than normal

[2] equal stress is often placed on all syllables in an utterance

[3] silent pauses may occur at the initiation of a word or b/w syllables; may be the result of articulatory groping

[4] the normal variations in pitch and loudness in an utterances may be reduced

Question 16

AOS Respiration

Answer 16

• some individuals with AOS may not be able to take a deep breath when asked to do so on command
• will demonstrate halting, effortful movements
• this is voluntary; reflexive respiration is not affected by AOS

Question 17

AOS Ponation

Answer 17

• usually phonation is not impacted when the AOS is mild or moderate
• suspected difficulties is really related to the articulation issue where the Pt is struggling for the correct articulator placement

-in severe AOS though, the Pt may be unable to prolong a vowel for both spontaneous and voluntary tasks
Duffy suggests that this usually occurs in the first 1-2 wks following the onset of the apraxia

Question 18

Differential Diagnosis

Answer 18

AOS or aphasia:
[1] does the Pt have pure AOS?; aphasia without AOS?; aphasia and AOS

[2] is the deficit true AOS or a type of paraphasia seen in Pt’s with some aphasias?

[3] is the deficit AOS or just nonfluent language errors associated with a Broca’s aphasia?