CH 6. - Ataxic Dysarthria Flashcards
Neuromotor Basis of Ataxic Dysarthria
- Impaired coordination due to damage of cerebellum
- motor control (breakdown in timing & coordination)
Neural components of the cerebellar control circuit
Medial zone (vermis & intermediate part of hemisphere)
Lateral zone (lateral hemisphere)
Medial zone (cerebellar control circuit)
(Vermis & Intermediate part of hem)
Connections to vestibular & brainstem nuclei, and regions of the spinal cord
Contributes to:
axial & trunk control
balance & posture
vestibular reflexes
coordination between head & eye muscle tone
Lateral zone (cerebellar control circuit)
(Lateral Hemisphere)
Connections to the motor & premotor cortex, comparator (comparing intended/actual performance), function is modified by motor experience
Contributes to:
coordination of voluntary move
planning & intiation of move
sensorimotor learning
muscle tone & tremor
Lateralization of motor control as it relates to cerebellar control circuit
- Each cerebral hemisphere controls the contralateral side
- Cerebellar hemisphere coordinates movement on that same side
3 key functions of the cerebellum
BALANCE: connect with vestibular system of inner ear
POSTURE: connect with spinal cord
ARTICULATION: connect to cerebral hemispheres for subconcious coordination of rapid movements
etiologies for ataxic dysarthria
Degenerative (ALS, Multiple Sclerosis)
Vascular (stroke)
Traumatic (post operative, tumor, TBI)
Friedreich’s Ataxia, Posterior Fossa Tumors, Purkinje cells
3 general symptoms associated with cerebellar control circuit damage
INNACURACY OF VOLUNTARY MOVEMENTS
SLOWNESS OF MOVEMENT
HYPOTONIA
Speech-related complaints for ataxic dysarthria
- Drunken quality of speech
- Deterioration of speech w/ limited alcohol consumption
- Difficulty coordinating speak/breathe
- Sometimes bite cheek/tongue while speak/eat
- Less frequent swallowing complaints in comparison to flaccid/spastic
Distinctive speech features of ataxic dysarthria
Reduced vital capacity & total lung volume
Reduced maximum phonation time
Paradoxical respiratory activity
Abrupt & irregular respiratory movements
