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Apraxia
Apraxia results from an impaired ability to generate the motor programming for speech
movements. It is not a disorder in the transmission of messages to the speech musculature.
Apraxia is a planning/programming problem, not a movement problem like dysarthria. Apraxia
is a problem in assembling the appropriate sequence of movements for speech production or the
execution of the appropriate serial ordering of sounds for speech. The primary disorder is an
inability to program articulatory movements. Apraxia is always the result of a central nervous
system lesion and is a cortical problem.
In apraxia, errors are inconsistent and unpredictable. Different error patterns occur in
spontaneous speech versus repetition. Students’ spontaneous speech contains fewer errors than
does his/her speech in repetition tasks. When producing rote material or that which has become
automatic, the student will speak clearly. Substitutions are the most common type of error.
Approximations of the targeted phoneme are also expected. Other types of errors found in
apraxic speech include repetitions, additions, transpositions, prolongations, omissions and
distortions. Errors are often perseveratory in nature. As in stuttering, the anticipation of errors
causes dysfluent speech. Apraxic speech is full of groping along with trial and error types of
articulatory movements. This could be due to the anticipation of errors. For a student with
apraxia, vowels may be easier to produce than consonants. Problems with voice and resonance
are not symptomatic of this disorder.
Apraxia of speech may occur without concomitant swallowing problems. The movements of the
velum, lips, tongue and jaw will only be impaired during speech. Diadochokinesis will be slow
and abnormal, and syllables will be produced out of order.
Characteristics of apraxia in children according to Smit (2004)
Significantly reduced intelligibility Severely limited consonant inventory with many omissionsReduced syllable inventory Assimilation and transposition errors
Vowel errors Groping evident in articulation attempts
Inconsistent production of the same word Performance reduces with increased sentence length and complexity
Prosodic errors Better performance in single words than in sentences
Isolated instances of well articulated words that are not evident again
Characteristics in the history of students with apraxia
Poor feeding in infancy Drooling past an age typically seenSensory aversions Relative quiet infancy
Generally clumsy Slow progress in treatment
Nonspeech Characteristics
Resists imitating modeled wordsUses gestures to relay message Avoids speaking
Relies on family members as translators
Concomitant Characteristics
Receptive language skills above expressive language Poor vocabulary and wordfindingSymptoms of central neuromotor disorder: perseveration, difficulty inhibiting contradictory behaviors, fatigues easily
Great article, Monica. Thanks for sharing. This wasn't a topic that I had any information on. As usual, you are my one-stop-shop for all things speech related.
-Francesca
PS: Did you find your lovely Sassafras?
Good article. Did you know the guy who plays Harry Potter also has apraxia? See, he went on to make millions. I'm sure Jack will do the same. :)
Thanks Francesca! And, no, Sassafras is still missing.
I didn't know that, Angela, about Harry Potter...very interesting!