1
Speech and the Hearing-Impaired Child Theory
and Practice Ch. 13

• Vowels and Diphthongs
• Vowels are formed when sound produced at the
  glottal source is selectively filtered and
  resonated in the vocal tract
• English has 15 vowels and 4 diphthongs which are
  commonly encountered
• Movements of tongue and lips is correlated as
  tongue moves toward front of mouth, lips are
  spread (examples eat, it, at)
• As tongue moves back, lips are rounded (examples
  caught, boat, boot)

2
Speech and the Hearing-Impaired Child Theory
and Practice Ch. 13

• Vowels and Diphthongs
• Most crucial variable in vowel production is the
  point at which the tongue creates the greatest
  degree of constriction in the vocal tract
• Typically this is the highest point in the
  tongues profile
• Vowels may also be differentiated by degree of
  tension in tongue and jaw during production
• Tense tongue spread, Lax narrower
• Examples of tense-lax pairs eat/it, ate/et (as
  in etcetera)
• Some words contain both members of a tense-lax
  pair (spoon pronounced spoon or spoo-on)

3
Speech and the Hearing-Impaired Child Theory
and Practice Ch. 13

• Vowels and Diphthongs
• Formant frequencies of vowels determined by
  length of vocal tract
• But relative shape of tract (and overall acoustic
  pattern) will be similar for all speakers
• Men, women, and kids will all have tongue in high
  back position for boot and high front for
  beet
• Listeners have a normalization process after
  hearing the first few syllables of an utterance,
  such that exact formant frequencies are generally
  unimportant to comprehension
• Analogy handwriting analysis

4
Speech and the Hearing-Impaired Child Theory
and Practice Ch. 13

• Vowels and Diphthongs
• Lieberman (1973) suggests that listeners use
  vowels in eat, ought, and boot to calibrate
  speakers
• Studdert-Kennedy (1975) argues that vowels are
  only normalized in a consonant context
• Normalization in HI not yet studied
• In running speech, vowels are coarticulated and
  not necessarily produced same way each time
• However, speakers have an ideal vowel target in
  mind

5
Speech and the Hearing-Impaired Child Theory
and Practice Ch. 13

• Vowels and Diphthongs
• Ling says that HI kids must establish their own
  ideal vowel targets through sustained production
• Without ideal targets, HI kids may neutralize all
  vowels, thereby reducing intelligibility
• Diphthongs when two vowels are produced as a
  glide
• Examples pie, cow, toy, play, here
• Dialectical differences largely due to vowels and
  diphthongs
• Is can one syllable or two?

6
Speech and the Hearing-Impaired Child Theory
and Practice Ch. 13

• Articulatory Targets and Formant Values
• Use Table 13.A as a guide
• Teacher should follow 4 steps
• 1. Ensure that childs tongue rests on or near
  the lower front teeth for all vowels except those
  associated with r, and that the velum is raised
  during production of all vowels (no nasal
  resonance)
• 2. Know own articulatory patterns thoroughly
• 3. Develops subskills as described
• 4. Discourage exaggeration (teeth no more than 1
  cm apart when jaw is open)

7
(No Transcript)
8
Speech and the Hearing-Impaired Child Theory
and Practice Ch. 13

• Subskills and Teaching Strategies
• All vowels require
• 1. Differential shaping of the vocal tract to
  produce the required formant structures
• 2. Ability to maintain each target vocal tract
  configuration for at least three seconds
• 3. Rapid repetition of each vowel target
• 4. Rapid alternation of the articulators so they
  can assume their target positions for each vowel
  easily from their previous position
• 5. Independent control of the larynx (sound
  source) and the articulators (sound filter)

9
Speech and the Hearing-Impaired Child Theory
and Practice Ch. 13

• Subskills and Teaching Strategies
• The extent to which vowel differentiation occurs
  spontaneously usually depends on the amount of
  residual hearing that is present and the extent
  to which it is used. The wider the frequency
  range of the childs hearing, the greater the
  variety of vowels he will be likely to produce if
  appropriate hearing aids and extensive exposure
  to speech have been provided. The childs
  orosensory-motor differentiation of spontaneously
  produced vowel patterns will also depend on the
  effectiveness of the reinforcement that has been
  supplied. p.230

10
Speech and the Hearing-Impaired Child Theory
and Practice Ch. 13

• Teaching Strategies Related to Vocal Production
• Must be determined for each child according to
  extent of and use of residual hearing
• All other variables (age, previous experience)
  are of secondary importance
• Kids with hearing up to 3,000 Hz may be expected
  to imitate and identify all vowels through use of
  audition
• Only when attempts to teach using audition have
  failed should teacher employ touch or vision

11
Speech and the Hearing-Impaired Child Theory
and Practice Ch. 13

• Teaching Strategies Related to Vowel Production
• Before strategies involving primarily touch and
  vision are adopted, the child must first have
  abundant spontaneous vocalization and elementary
  control of voice patterns.too often we see
  teachers who have not made exhaustive efforts to
  exploit residual hearing, have not provided
  regular and plentiful auditory models, and have
  not given appropriate reinforcement for
  vocalizations varying in phonetic quality. p.231
• Failure to optimize natural speech development
  may critically and permanently impair the
  childs attitude toward speech communication