Apraxia of speech
- 2. • A neurologic deficit in the production of speech sounds. • Errors are not caused by muscle weakness, abnormal muscle tone, reduced range of movement, or decreased muscle steadiness. • Errors are caused by a deficit in the ability to accurately sequence the movements needed to produce speech sounds • Greek word praxis – performance of action • Apraxia – without action • Dyspraxia – disordered actions
- 3. • Indl with apraxia – not without movement • Problem with selecting and sequencing of movements needed to produce speech • Several types of aparaxia, of which AOS is only one of the subcategories • Main two types – Ideational apraxia - Ideomotor apraxia
- 4. • Ideational – inability to make use of an object or gesture bc the indl has lost the knowledge (idea) of the objects or gestures function • Means cannot make proper use an object or gesture bc they no longer know its purpose • Uncommon disorder – result from damage to the left parietal lobe • Usually symptoms can be masked easily by accompanying disorder like aphasia • Sometimes it resolves quickly when caused by a stroke
- 5. • Ideomotor apraxia – disturbance in the performance of the movements needed to use an object, make a gesture, or complete a sequence of individual movements • AOS – one of the ideomotor apraxia • Not lost their knowledge of an object or gesture • They have a deficit in the ability to carry out the motor plan needed to use an object or make a gesture
- 6. • Ideomotor apraxia typically affects voluntary movements more often than spontaneous or automatic movements • Movement sequencing is easier when actually manipulating a real object compared with only pantomiming its use • Completing a movement sequence is easier when given gestural command (imitation) • Movement sequencing errors can be sometimes inconsistent on repeated attempts of the same action
- 7. • 3 subcategories of ideomotor apraxia • Limb apraxia – inability to sequence the movements of the arms, legs, hands, or feet during a voluntary action • Most often the result of left hemisphere damage • Nonverbal oral apraxia – buccofacial apraxia, facial apraxia, orofacial praxia, lingual apraxia • Deficit in the inability to sequence non verbal voluntary movements of the tongue, lips, jaw and other associated oral structures
- 8. • Difficulty protruding tongue, whistling, biting the lower lip, puffing out the cheeks • Seen in indl with left hemisphere damage, often co-oocurwith aphasia • Able to perform automatic oral movements without difficulty- little clinical significance • Third category - AOS
- 9. AOS • A deficit in the ability to select and sequence the motor commas needed to correctly position the articulators during the voluntary production of phonemes. • It can co-occur with limb or non-verbal apraxia • Caused by damage to lt frontal lobe, especially near Broca’s area • Majority of cases – AOS co-occurs with Broca’s aphasia • Common to co-occur with UUMN dysarthria (Duffy, 2005)
- 10. Neurologic basis
- 11. Causes of AOS • Disorders that damage the MSP • most common site – damage to left perisylvian area • Injuries to insula and basal ganglia • A retrospective study at the Mayo Clinic – 155 quasirandomly selected cases – Duffy (2005) - 49% of cases – stroke Strokes affecting the perisylvian area of lt hemisphere, primarly frontal and parietal lobes
- 12. - second most common – 27% - degenerative disease- Alzheimer’s disease, PPA, Creutzfeldt-Jakob disease Usually associated with diffuse brain damage - third- 14%- Trauma Surgical trauma – aneurysm repair, removal of a tumor, hemorrhage evacuation Closed head injury – very few Remaining cases – tumors in lt frontal lobe, seizure d/o, undetermined etiology or multiple causes like lt hemisphere stroke and dementia