Ch.7 Physiology Articulation

Instrumentation and Articulation

• Measurement of Speech Sounds:

• The utilization of advanced voice analysis software, such as PRAAT, enables detailed spectrogram analysis to visualize and measure speech characteristics.

• Computerized speech labs provide a comprehensive way to assess several aspects of vocal function, including pitch, loudness, and duration of speech sounds.

• Articulation Assessment:

• In-depth assessment techniques, including vowel and consonant-vowel matching, were analyzed through spectrograms to gauge articulation precision.

• While many instruments are primarily research-based, their academic findings can inform clinical applications, potentially enhancing treatment approaches.

• Instruments Used:

• Iowa Oral Performance Instrument (IOPI):

  • Effectively measures strength and endurance of the tongue and lips critical for both speech and swallowing.

  • The design allows patients to work with a tongue bulb providing measurable feedback to enhance endurance and strength over time.

  • This instrument's evidence-based effectiveness has been consistently supported by studies showing significant improvements in patient compliance through motivational feedback mechanisms.

• Oral Motor Exercises:

• Primarily aimed at treatment for dysarthria, a motor speech disorder resulting from neurological damage, these exercises help improve oral motor strength and endurance essential for effective speech production.

Speech Function:

• Understanding the Interaction of Articulators:

• The balance between mobile and immobile articulators is crucial for efficient speech production.

• Mobile Articulators:

  • Lips:

    • Act as primary sites for muscle insertion, and their functionality, including closure and pucker, is essential for accurate verbal and non-verbal communication.

    • The lower lip, utilizing greater velocity and force, plays a critical role in articulating sounds during both speech and eating activities.

  • Mandible:

    • Performs a supportive role, actively participating in carrying the lips, tongue, and teeth necessary for effective speech production; peripheral stability of the mandible directly impacts intelligibility.

  • Tongue:

    • Unique in functioning as a muscular hydrostat, allowing for extensive mobility without skeletal support, it can make precise movements due to coordination between intrinsic (for shaping) and extrinsic (for positioning) muscles.

    • Essential tongue movements for speech include elevation/depression of the tongue tip and lateralization, impacting articulation and phoneme production significantly.

Velum (Soft Palate):

• Acts as a vital structure to separate the oral from the nasal cavities, influencing both resonance and the prevention of food entering the nasal cavity during swallowing.

• Surgical repairs for cleft palates can have profound implications on speech resonance and overall communication effectiveness.

• Nasal Assimilation:

  • Examines how the nasality of sounds can be affected by nearby phonetic contexts, altering speech production outcomes.

Consonants vs. Vowels:

• Consonants:

  • Categorized by parameters such as place of articulation (e.g., bilabials P and B; labiodentals F and V; alveolars T and D), manner of articulation (e.g., stops, fricatives, nasals), and voicing distinctions (e.g., cognate pairs like T vs. D).

• Vowels:

  • Characterized by being produced with an open vocal tract, defined through parameters of tongue height (high, mid, low) and tongue position (front, central, back). The vowel quadrilateral serves as a visual representation of vowel sounds based on these articulation features.

Phonological Systems and Theories of Articulation:

• Feedback Systems in Speech Production:

  • The production of speech involves intricate feedback systems with proprioceptive and auditory mechanisms that ensure constant adjustments in articulation.

• Key Theories:

  • Associated Chain Theory: Proposes that motor acts are learned sequentially, but it lacks emphasis on the dynamic nature of speech production.

  • Central Control Theory: Suggests that the brain orchestrates all patterns for articulation without feedback considerations.

  • Dynamic Action Theory: Emphasizes the interaction and coordination of anatomical structures impacting speech, allowing for variability in production patterns.

  • DIVA Model: Focuses on the coordination of directions and velocities for articulation, considering external influences from surrounding phonetics to adjust sound variations during speech.

Speech Development:

• Prenatal factors influence the development of the lip and palate, and such anatomical variations have critical implications for conditions like cleft lip and palate.

• As speech develops as a fine motor skill following the acquisition of gross motor skills, the interplay of reflexes with communicative efforts significantly influences ongoing communication abilities as children grow.

Pathologies Affecting Articulation:

• Temporary anatomical changes, such as trauma to the teeth, tongue, or mandible, can lead to challenges in articulation but often resolve over time with healing.

• Neurogenic disorders, including amyotrophic lateral sclerosis (ALS), apraxia, and dysarthria, are associated with neurological conditions, having a profound impact on an individual’s speech production capabilities, often necessitating specialized interventions.