chapter 7 Flashcards
ataxic dysarthria
motor speech disorder often due to damage to cerebellum or its neural pathways
primarily results in speech errors that are
articulatory and prosodic, giving speech unsteady and slurred quality
neurologic basis of ataxic dysarthria
caused by damage to cerebellum or neural pathways that connect cerebellum to other parts of CNS
ataxia
greek word for “lack of order”; widespread incoordination
cerebellum
primary function: coordinate timing and force of muscular contractions
-processes sensory information from all over body and integrates information into execution of movement
cerebellar peduncles
communicates with rest of CNS through three bundles of neural tracts called cerebellar peduncles
inferior peduncle allows cerebellum to
receive sensory info from entire body about position of body parts, recgonize what body is doing during movement and whether motor impulse to muscles is accomplishing intended results, monitor timing and force of movements while performed
middle peduncle allows cerebellum to
receive preliminary info from cortex regrding planned movements, coordinate planned movements by integrating sensory info from body with individuals experience of what appropriate movement should be, smoothing and refining according to current conditions
-when you;re falling this is what makes you try to steady yourself and not fall
superior peduncle
have main output to rest of CNS, send its processed motor impulses to motor areas of cortex, completing corticocerebellar control circuit
cerebellar control circuits
neurons that course through 3 cerebellar pathways
extrapyramidal system
makes rapid adjustments in timing and force of movements to compensate for unexpected changes in circumstances of movement
causes of ataxic dysarthria
damage to cerebellum or its control circuits causing difficulties coordinating voluntary movements
cerebellar ataxia
movements deficits of timing, force, range, and direction
vermis
midpoint of cerebellum between cerebellar hemispheres upon which speech coordination is highly dependent
stroke
Blockage of arteries serving the cerebellum
toxic conditions
-lead and mercury posioning
-long and short term alcohol consumption
exposure to chemicals such as acrylamide and cyanide
toxic levels that may not be irreversible
phenytoin (dilantin) antiseizure drug
metabolic conditions
vitamin E or b12 deficiency, severe cases of hypothyroidism, hereditary disorders such as wilson’s disease
TBI
trauma to cerebellum tends to be diffuse, as with most head injuries
-cerebellar peduncles especially vulnerable to twisting and rotational forces because cerebellum essentialy an appendage attached to brainstem
tumors
extent of ataxic dysarthria depends on location and size of tumor
metastatic tumors
most common; formed when primary tumor sheds cancerous cells that seed a secondary tumor
low-grade astrocystoms
slow-growing type of tumor appearing frequently in cerebellum, especially in children
hemangioblastomas
benign tumors of proliferated blood vessels found occasionally in cerebellum
speech characteristics of ataxic dysarthria
movements appear poorly coordinated, problems controlling timing/force for speed, slurred, montonous articulation, primarily disorder of articulation and prosody, scanning speech
scanning speech
term to describe ataxic dysarthria, describing slow, deliberate production of syllables, with each syllable in a word receiving equal stress
articulation
significant problem, imprecise consonant production, distorted vowels, irregular articulatory breakdowns, decomposition of movement
distorted vowels
gives slurred quality, caused by cerebellar damage disrupting timing, force, range, and direction of movements
decomposition of movement
manifestations of cerebellar dysfunction, where instead of smooth coordinated movements, they are distinct and jerky
prosody
equal and excess stress the distingushing characteristic of ataxic dysarhria, prolonged phonemes and prolonged intervals between phonemes, monopitch and monoloudness
phonation
few phonatory deficits noted in ataxic, harsh vocal quality, voice tremor
harsh vocal quality
caused by decreased muscle tone in laryngeal and respiratory structures, preventing full contraction of the muscle groups
resonance
hypernasality, hyponasality
hyponasality
more present, intermittent, caused by timing errors between muscles of velum and other muscles of articulation
respiration
uncoordinated movements in respiratory muscles, contributing to speech deficits paradoxical movements
paradoxical movements
movements againist each other rather than in coordination; leads patient to speak on residual air, which can lean to increased rate of speech, decreased loudness, and harsh vocal quality
key evaluation tasks for ataxic
AMR, reading, conversational speech, and repeating sentences containing numerous multisyllabic words
speech alternate motor tasks
slower than normal, difficulty maintaining steady rhythm with repeition, severe cases: speed up abruptly then slow down, AMRs are more susceptible in ataxic compared to any other dysarthria
treatment
damage affects speed, force, and timing of movements of articulators, resulting in uncoordinated movement; most evident speech errors related to artic and prosody
respiration
do not need to address strengthening, concentrate on controlling airlfow more accurately during speech, as uncoordinated movements of respiratory muscles cause speech on residual air, affecting prosody and phonation
tasks to help improve breath control during speech
slowed controlled exhalation, speak immediately on exhalation, stop phonation early, optimal breath group: teaching how many syllables or words can be said clearly on one full inhalation
tasks to help improve breath control during speech
slowed controlled exhalation, speak immediately on exhalation, stop phonation early, optimal breath group: teaching how many syllables or words can be said clearly on one full inhalation
prosody
prosodic problems involve rate, stress, intonation
rate control prosody
slow irregular rate characteristic of ataxic dysarthria, but may attempt to speak too rapid for speech capabilities
rate control tasks
reciting syllables to a metronome, finger or hand tapping, cued reading material
stress and intonation prosody
concentrate on developing more natural pitch and loudness variations in connected speech; exercises: contrastive stress drills, pitch range exercises, intonation profiles, chunking utterances into syntactic units
