Understanding Voice Dynamics and Function

What is Voice?

• Voice is the audible sound produced by phonation-- the process of sound production through vocal fold interaction with exhaled air.
• Voice is defined as a complex process that serves many functions, including:
  • Expressing emotions
  • Carrying words
  • Producing music
  • Conveying meaning through phrasing, control of pitch, and dynamic range
  • Serving as an emotional outlet (laughing and crying)
  • Revealing the inner self
  • Drawing people in or pushing people away (soothing versus hard voice)
  • Revealing physical state (crying, weakness from illness)

Defining "Normal" Voice

• There are measures of vocal function, but there is no objective, standard method for determining if a voice is "normal".
• Measures of vocal function are useful but need further development (tasks, norms, standardization, etc.)
• SLPs must rely on auditory perception in addition to instrumental assessments.
• Perceptual judgments depend on age, gender, cultural background, education, vocal training, and the listener characteristics.

Voice Disorder

• A voice disorder exists when pitch, loudness, quality, and/or flexibility differ noticeably from voices of others of similar age, gender, and cultural group.

Perceptual Parameters of Voice

• Pitch:
  • Normal: appropriate for the age and gender of the speaker.
  • Abnormal: too high, too low, monotone, pitch breaks, reduced pitch range.
• Loudness:
  • Normal: loud enough to be heard under normal circumstances
  • Abnormal: too soft, too loud, monoloud, reduced loudness range
• Quality:
  • Normal: clear, absence of noise
  • Abnormal: lack of clarity, presence of noise, discordance.
• Flexibility/Variation:
  • Normal: a variety of pitch, loudness, and quality.
  • Abnormal: limited range of pitch, loudness, and quality.

Common Terms to Describe Abnormal Voice Qualities

• Roughness: Perception of noisiness and/or lack of clarity – related to the amount of aperiodicity and noise in the acoustic signal.
• Breathiness: Perception of audible escape of air during phonation – related to incomplete glottic closure and increased levels of air flow during phonation
• Strain or Tension: Perception of increased effort to produce phonation – may be reflected by increased subglottal pressure.
• Tremor: Rhythmic variations in pitch and loudness which are not under voluntary control.
• Sudden Interruption of Voicing: Perceptual sign of a sudden and unexpected abduction of vocal folds, or delayed adduction from unvoiced to voiced phonemes.
• Diplophonia: Two pitches perceived at once.

Other Behaviors

• Stridor: Noisy breathing, involuntary sound accompanying inspiration and/or expiration.
• Excessive throat clearing: Perceptual sign of voice disorder when it occurs frequently and consistently.
• Aphonia: Absence of a definable vocal tone – voice is whisper-like, but without phonation (consistent vs. episodic).

Clinical Perceptual Evaluation of Voice - CAPE-V

• Purpose: To describe the severity of auditory-perceptual attributes of a voice problem
• Rating:
  • Overall severity
  • Roughness
  • Breathiness
  • Strain
  • Pitch
  • Loudness
  • Additional Features
• Measurements:
  • Mild/Mod/Severe
  • 0-100 scale
  • Consistent/Inconsistent

Clinical Perceptual Evaluation of Voice - CAPE-V (continued)

• The CAPE-V protocol includes three vocal tasks:
  • Sustain /a/ and /i/ for 3-5 seconds in duration.
  • Produce 6 sentences.
  • Spontaneous speech: "Tell me about your voice problem".

Incidence of Voice Disorders

• Adults:
  • Estimated 3% to 9% of the total population has a voice disorder.
  • Studies report ranges from 12% to 35% for the elderly, mainly based on retrospective review.
• Children:
  • Studies using small sample sizes report figures as high as 23.4%.
  • Studies using larger sample sizes report ranges from 3-6%.
• Occupation-Based Statistics:
  • Voice disorders are more common in jobs that require high levels of voice use.
  • Occupations with high voice use risk are: Singer, Counselor/Social Worker, Teacher, Telemarketer, and Ticket Sales.

The Voice Team

• Primary members: MD (laryngologist) and SLP
• The MD is responsible for medical diagnosis and management.
• The SLP is responsible for assessment of vocal function and behavior and for providing voice therapy services.
• Other specialties are called upon as needed (e.g., neurology, radiology, psychology, gastroenterology, teachers with singing/voice coaching).

This quiz explores the concept of voice, including its production and functions such as emotional expression and communication. It also delves into the challenges in defining what constitutes a 'normal' voice. Test your knowledge on the complexity of vocal function and its assessments.