Most clinicians know that doing a motor speech evaluation is an overwhelmingly tedious task, especially when you only have 1-2 hours to complete the assessment. I have compiled a list of factors that should be evaluated to arrive at an accurate diagnosis.
1. Case History: Primary and secondary medical diagnosis, site of lesion in CNS (MRI, CT scans), and date of onset/course of problem. Ideally, the patient provides information putting on display the salient features and severity of the problem.
2. Patient Interview: Basic data, family/home situation, description including onset, perception of speech, how it feels to speak, changes in appearance, associated deficits, swallowing difficulty, physical/mobility status, and earlier instances of nervous system damage.
3. Cognitive / Communication Assessment: Orientation, comprehension of two-step directions, and expressive language.
4. Respiration: Subglottic air pressure for phonation (damage can cause decreased air, short phrases, and breathy vocal quality).
5. Phonation: Vocal fold vibration dependent on complete adduction of folds and sufficient subglottic air pressure to cause folds to vibrate (damage can cause hypotonicity or hypertonicity).
6.Resonance: Provides proper tonality for oral and nasal phonemes, dependent on functional raising and lowering of velum (damage can cause weakness or slowness – incomplete velopharyngeal closure resulting in hypernasality).
7. Articulation: Requires appropriate timing, direction, force, speed and placement of oral structures (damage to nerves most commonly results in imprecise consonants).
8. Prosody: Melody of speech (damage can effect pitch, loudness, prolonged intervals between syllables or words).
9. Oral Mechanism Exam (OME): Tone, strength, and range of motion of oral motor musculature.
7. Alternating Motion Rate (AMR): Assess speed (slow/fast), dysrhythmia, uneven loudness, uneven pitch, tremor, duration between syllables, blurring between syllables, hypernasality, nasal emission, restricted amplitude of lips or jaw, imprecise/distorted consonants (average /p/ and /t/ – 5-7 reps per second or 30-35 reps in 5 seconds, /k/ is slightly slower).
9. Sequential Motion Rate (SMR): More difficult than AMR; average is 5 per second. Useful in diagnosing apraxia. With apraxia, patient may exhibit delay in starting, may exhibit phoneme substitutions, incorrect sequencing of syllables, and groping for correct placement.
10. Stress Testing: Screen for Myasthenia Gravis – a disorder that causes rapid fatigue of muscles during sustained motor tasks (patient counts quickly from 1-100; assess for rapid deterioration in articulation, resonance, or phonation).
11. Test for nonverbal oral apraxia: If there is evidence of groping or inability to sequence oral movements, test for apraxia. May observe groping behaviors, hesitations during non-speech oral movements, disrupted sequence of oral movements that are not verbal, can have nonverbal oral apraxia without apraxia of speech and apraxia of speech without nonverbal oral apraxia.
12. Test for apraxia of speech: Inability to sequence voluntary movements for speech. May demonstrate hesitations, revisions, omissions, inconsistent errors in articulation, automatic and emotional speech are usually intact, as are complete automatized sequences such as counting, days of week. Family will usually be surprised that clear utterances occur during emotional situations. To assess, have patient repeat words. If unable to repeat, present in written form. The goal is to increase complexity. List should also contains low frequency words. If patient has apraxia of speech, he/she will observe many sequencing/articulation errors. Next set of single syllable words begin/end in same phoneme should be easier to produce; however, if patient has difficulty it will give you an indication of the severity of apraxia.
13. Functional Communication Measure: Level 0 – unable to test, Level 1 – production of speech is unintelligible, Level 2 – spontaneous production of speech is limited in intelligibility; some automatic speech and imitative words or consonants/vowel (CV) combinations may be intelligible, Level 3 – spontaneous production of speech consists primarily of automatic words or phrases w/ inconsistent intelligibility, Level 4 – spontaneous production of speech is intelligible at the phrase level in familiar contexts: out of context speech is generally unintelligible unless self cueing and self-monitoring strategies are applied, Level 5 – spontaneous production of speech is intelligible for meeting daily living needs; out of context speech requires periodic repetition, rephrasing, or provision of a cue, Level 6 – spontaneous production of speech is intelligible in and out of context, but the production is sometimes distorted, Level 7 – production of speech is normal in all situations.