Transcript How Knowledge of Speech Acoustics Aids Audiologists

Speech
Acoustics
Audiologic Rehabilitation
for Children
SPA 6581 – Spring 2015
Lecture Date: 02/09/2015
Speech Acoustics
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Helpful in the following:
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Can be used to determine and counsel regarding expectations
“Is it a programming thing or a patient thing?”
Maximize whatever auditory stimulation in order to enhance
stimulation of auditory pathways
Knowledge of speech acoustics helps us:
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Bridge the disciplines of audiology and habilitation
Judge what speech information is available to a child through
their “aided” hearing
Teach parents what the child can do or has the potential to do
with his/her aided hearing
Select strategies to facilitate the processing of spoken language
through audition
Choose which phonemes can be learned through audition
alone, and which may require different strategies (visual or
tactile)
Collaboration
A
speech-language pathologist or
educator may report the following:
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Specific phonemes missed
Suprasegmentals missed
Quality of speech
Identifying vs. detection of sounds
Level of consistency with responses
Assessment
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It is important to constantly evaluate performance with regards to
speech perception, as it will determine if “progress” has been
made.
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The periodic evaluations may influence modifications to
programming and/or communication mode recommendations
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Great news! We already obtain data as part of our routine clinical
protocols! What is important, is how we use it.
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word recognition
phoneme recognition
sentence testing
background noise
Etc.
Four Levels of Auditory Skills
Detection
Discrimination
Identification
Comprehension
Detection
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The ability to respond to presence and absence of sound
In response to sound, a child may:
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In therapy, what types of sounds can we use to determine
a child’s detection level?
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Turn head
Cease activity
Startle
Environmental sounds
Speech sounds
Music
How can we elicit detection?
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“I hear that!”
Visual – pointing to ear
Hand over hand, modeling, etc.
Discrimination
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The ability to perceive differences in
suprasegmental features or in the acoustic
properties of speech sounds
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This level can be particularly helpful in determining
if there is a “speech” or an “auditory” problem
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Same vs. Different
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“ahhh” vs. “ahhh ahhh ahhh” – duration
“oooo” vs. “eeee” – pitch
“AHHHH” vs. “ahhh” - intensity
Identification
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The ability to reproduce a speech stimulus by naming
or identifying by pointing to a picture or repeating
what was heard
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Example:
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Early Speech Perception Test – Low Verbal, Pattern
Perception Subtest:
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Ball, baby, hotdog, icecream cone
More than just same or different discrimination. This task
involves auditory skills, pragmatic skills (taking turns), joint
attention
*What you will often see with pediatric patients is
imaginary play with the objects! This is a good thing! You
want to see this. Why?
Comprehension
 The
ability to understand the meaning of
what has been heard
Auditory Development:
A More Detailed Perspective
Auditory Detection or Attention
Auditory Discrimination
Auditory Self-Monitoring or Feedback
Auditory Identification or Association
Auditory Memory
Auditory Sequencing
Auditory Processing
Auditory Understanding
Nancy S. Caleffe-Shenck, M.Ed., C.E.D., CCC-A, Cert. AVT (Adapted from Doreen Pollack, 1985)
Ling 6-7
Sound Test
Acoustic Basis and
Description
Purpose
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Developed first by Daniel Ling
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Quick and easy way to verify that a child detects
the vowel and consonant sounds of spoken
language.
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Allows parents, professionals, and teachers to
know the child’s distance hearing.
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Also allows for device troubleshooting and
verification of function.
Use of Ling 6-7: Levels of
Auditory Skills
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be utilized for all of the four main
levels:
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Detection
Discrimination
Identification
Comprehension
Sound Selection
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/m/ corresponds to 250 Hz, +/- ½ octave
/u/ is like a narrowband of noise corresponding to 500 Hz on the
audiogram, +/- ½ octave
/a/ corresponds to 1000 Hz, +/- ½ octave
“sh” is a band of noise corresponding to 2000 Hz, +/- ½ octave
/s/ is a band of noise corresponding to 4000 Hz, +/- ½ octave
/i/ has a first formant (resonance of the vocal tract) around 500 Hz,
and a second formant around 2000 Hz; the second formant must
be heard in order for the listener to be able to distinguish between
front and back vowels
The silent interval is really a seventh “sound” that is necessary to
track false positive responses. Other reasons for using the silent
interval?
Applications & Instructions for
the Ling 6-7 Sound Test
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Conditioning
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Hand-over-hand facilitation
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Modeling
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Occupying attention with “quiet” toys
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Eliminate visual cues
Speech Information & Key Frequencies
250 Hz
500 Hz
1000 Hz
2000 Hz
4000 Hz
First formant of
vowels /u/ and /i/
First formants of
most vowels
Acoustic cues for
manner of
articulation
Acoustic cues for
place of
articulation
Fundamental
frequency of
female and
children
Harmonics of all
voices (male,
female, child)
Second formants of
back and central
vowels
Key frequency for
speech intelligibility
Nasal murmur /m/,
/n/, and /ng/
Voicing cues
C-V and V-C
transition
information
2nd and 3rd formant
information for front
vowels
The key frequency
for /s/ and /z/
audibility is critical
for language
learning:
-plurals
-idioms
-possessives
-auxiliaries
-third person
singular verb forms
-questions
-copulas
-past perfect
prosody
Nasality cues
Some plosive bursts
C-V and V-C
transition
information
Suprasegmental
patterns (stress,
rate, inflection,
intonation)
Suprasegmentals
Voicing cues
Acoustic
information for
liquids /l/ and /r/
Male voice
harmonics
Some plosive bursts
associated with /b/
& /d/
Suprasegmentals
Plosive bursts
Unstressed
morphemes
Affricate bursts
Voicing Cues
Fricative
turbulence
Consonant quality
Audibility vs. Intelligibility
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Audibility = simple act of detection
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Intelligibility = the individual must be able to discriminate
the word-sound distinctions of individual phonemes or
speech sounds
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Ling 6 (or 7) sound test
Environmental sounds
Etc.
For speech to be heard clearly, both vowels and consonants
must be available acoustically
Can speech be audible but not consistently intelligible?
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Yes. Even for a child with a minimal hearing loss.
Speech Banana
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Other lovely names!
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Represents concentrations of acoustic energy
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i.e., speech frequencies
Limitations of the audiogram?
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Speech pickle
Speech hotdog
Speech boomerang
Audiogram of familiar sounds including speech
Based on thresholds for tones or narrowband noise
Cannot truly show a child’s auditory learning experience or potential
Food for thought…
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If I can’t “sort by audiogram,” how do I know if a child has potential
to do well in developing spoken language through listening?
Formants
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Formants are concentrations of acoustic energy
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The brain identifies these patterns as specific vowels
and consonants
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Formants are used by our brain to identify all the
sounds of speech
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Each phoneme has distinctive patterns of formants
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Formants are visual representations of acoustic
information contained in speech
Acoustic Features of Speech
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Suprasegmentals (DIP)
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Suprasegmentals are
responsible for vocal
quality.
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Duration
Intensity
Pitch
Think: rhythm, stress,
intonation
Acoustic building
blocks of speech
 Segmentals
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Consonants
Vowels
Suprasegmentals: Duration
 Time
 Length
of the sound and how it starts,
changes, and finishes
 Vowels
are typically longer than
consonants
Suprasegmentals: Intensity
 Volume
 Force
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or power of the sound
Units are express in decibels
 Stress
patterns
Suprasegmentals: Pitch
 Frequency
 Measured
 Number
in Hz
of waves created by the
vibration from a sound which reach the
ear each second
Fundamental Frequency
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Rate at which the vocal folds vibrate
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The rate varies depending on whether the speaker is
a:
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Male
Woman
Child
125 Hz
250 Hz
325 Hz
Why is this information important?
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Who can they hear?
Why it is more difficult for them to hear one person or
another?
Expectations and counseling
Application Activity #1
 Use
the Interpretation of Acoustics of
Speech
 Determine
suprasegmental information
available to a child with aided hearing
out to 500 Hz, and out to 1000 Hz.
“Most hearing impaired child, when
provided with appropriate hearing
aids and sufficient auditory
experience can hear enough of the
speech signal to acquire naturalsounding, well-inflected voices,
because sufficient auditory cues on
prosody occur in the frequency
range below 1000 Hz (Ling, 1989).”
Segmentals
Vowels
Consonants
Segmentals: Vowels
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Produced by changing the resonance of
airflow through the oral cavity by altering the
position of the tongue and lips
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Tense/lax
Tongue height
Tongue placement
Lip rounding
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F1 is important for detection
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F2 is important for identification
Segmentals: Vowels
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Reference Vowels?
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/a/ = mid frequency/mid tongue
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/u/ = low frequency/back of tongue
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1st formant = 300 Hz
2nd formant = 900Hz
/i/ = high frequency/front of tongue
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1st formant = 800Hz
2nd formant = 1000Hz
1st formant = 300 Hz
2nd formant = 3000 Hz
Notice that they are all in the Ling 6 sound test
What is the significance of knowing the values of these vowels?
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If able to detect all three of reference vowels, they should be able to detect ALL
vowels out to 3000 Hz.
If able to identify all three of the reference vowels, they should be able to
identify all vowels out to 3000 Hz.
Speech Acoustics: Vowels
Application Activity #2
 Use
the Interpretation of Speech
Acoustics
 If
I say /u/, and the child responds with
“uh,” what do I know?
 If
I say /i/, and the child responds with /u/,
what do I know?
Vowel Formants
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Memorize this sentence for quick recall of the
order of the vowels and formants from low
frequency to high frequency.
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Who would know ought of art must again learn
and then take his ease.
What other way can this graph help you?
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When you are starting to work on discrimination
activities, you want to target vowels at the
extremes, to ensure the difference will be readily
heard.
Then you can start to work in to where the vowels
become more similar in acoustics.
Application Activity #3
A
child has aided hearing out to 500Hz.
 What
 Now
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vowel information is available?
try again:
Aided hearing out to 1000 Hz
Aided hearing out to 2000 Hz
Application Activity #4
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CA: 13 months, HA: 4 months
Aided in the speech banana out to 1500 Hz
Vocal behaviors: squeals, blows raspberries,
produces long sustained /m/, produces /a/
and “uh” with long an short duration,
beginning to vary pitch in vocal play
What vowel information is available?
Are F1 and F2 of early developmental
consonants available?
Segmentals: Consonants
 Produced
by restricting or interrupting
airflow along the vocal tract
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Manner
Place
Voicing
 Important
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formant(s)?
Depends on the consonant produced
Segmentals: Consonants
 Place
of
Production:
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Labial
Labiodental
Dental
Alveolar
Palatal
Velar
Glottal
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Manner of
Production:
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Plosive/stop
Fricative
Nasal
Affricate
Liquids/glides
Voicing Component:
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Voiced
Unvoiced
Speech Acoustics: Consonants
Vowels
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Consonants
Weak high-frequency
sounds
Energy focused at 2000
and 4000 Hz and
above
Carry 10% of the
energy of speech
BUT…90% of the
information needed to
perceive the
differences among
sounds
 Strong
lowfrequency energy
 Energy focused at
~250 to 500Hz
 Most powerful
sounds in English
 Carry 90% of the
energy of speech
(Talking Child, LLC, 2003)
(Talking Child, LLC, 2003)
Special Considerations
 Co-articulation
 Distance
 Noise
Co-articulation
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Co-articulation
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Affects consonants of highly consistent ways
Example:
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Consonants produced at the front of the mouth will lower
formants of preceding vowels (pg. 41, Ling – foundations of
spoken language)
Provides listeners with predictable ways to identify; as well as to
produce normal speech patterns
How could this help us with a child with high frequency
hearing loss?

If we are targeting /s/, and we want to make it more
acoustically salient, we can pair /s/ with /u/ in order to bring
down the high frequency of /s/ to perhaps make it more
audible for the patient.
Distance and Noise
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What is the most optimal distance for introducing a new
target for any of the four levels?
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6 inches away from microphone
Why???
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6 dB rule, the further you are from the sound source, the softer it
will be to the child.
Noise
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Children with hearing loss need 20 to 25 dB or better S/N ratio
Check consistently for noise in equipment
How can we use noise to challenge listening skills?
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Tape recorded information
Practice using the telephone
Developed for FIRST YEARS (http://firstyears.org/) - Listening Spoken Language Development Intervention
© Beth Walker, 2009
Auditory Learning Guide
SOUND AWARENESS
PHONEME LEVEL**
DISCOURSE LEVEL
(Speech and Environmental Sounds)
(Speech Babble)
(Auditory Processing of Connected Speech)
SENTENCE LEVEL
WORD LEVEL
Step 1 - Detect * the presence of
any speech syllable.
Step 1 - Imitate physical actions (before Step 1a - Imitate motions of nursery
speech imitations).
rhymes/songs with accompanying
vocalization.
Step 1 - Identify familiar stereotypic phrases
or sentences.
Step 1a - Identify and imitate approximations of “Learning To
Listen” sounds varying in suprasegmentals and vowel content, e.g.,
(a-a-a)/airplane , (u)-(u)/train , (oi) (oi) pig in isolation, at the end,
and then in the middle of a sentence.
Step 2 - Detect* vowel variety, [u]
[a] [l] and raspberries [b-r-r]
Step 2 - Imitate any phoneme that
child produces spontaneously when
given hand cue (or other cue).
Step 1b - Identify nursery rhymes or
songs.
Step 2 - Recall two critical elements in a
message.
Step 1b - Identify one, two, and three syllable words in
isolation, e.g., cat vs. chicken vs. kangaroo .
Step 2 - Answer common questions
with abundant contextual support,
e.g., “What’s that?”, “Where’s
mama?”, “What is ________doing?”
Step 3 - Recall three critical elements in a
message.
Step 2 - Identify words having the same number of syllables
but different vowels/diphthongs and consonants, e.g., horse
vs. cow vs. sheep .
Step 4 - Detect* the presence of
Step 4 - Imitate vowel and diphthong
environmental sounds at loud, medium, variety, e.g., [u], [ae], [au], [i], etc.
and soft levels at close range, at a
distance of 6-12 ft. and at a distance of
greater than 12 ft.
Step 3 - Identify a picture that
corresponds to a story phrase in a
three or four scene-story.
Step 4 - Complete known linguistic
messages from a closed set (ex: nursery
rhymes, songs, familiar stories).
Step 3a - Identify words in which the initial consonants are
the same but the vowels and final consonants are different,
e.g., ball vs. bike .
Step 5 - Detect* whispered [hae]
[hae] and [p] [p] [p]
Step 4 - Identify an object from several Step 5 - Answer common questions about a
disclosed and familiar topic: a) without pictorial
related descriptors (closed set).
Step 3 - Detect* consonant variety,
e.g., [m-m-m], [b^] [b^] [b^] and
[wa] [wa]
Step 3 - Imitate varying suprasegmental
qualities in phonemes (vary intensity,
duration, and pitch) aeeee (long) vs [ae ae]
(pulsed); [ae-ae] loud/quiet/whispered; [ae]
high/mid/low pitch.
Step 5 - Imitate alternated vowels and
diphthongs, e.g., [a-u] [e-I] [a-I]
cues b) over the telephone c) on audio/videorecording.
Step 6 - Detect* the sounds of the
Six Sound Test.
Step 6 - Imitate consonants varying in
manner (fricatives, nasals, and plosives).
Use phonemes previously produced, e.g.,
/h/ vs. /m-m-m/ vs. /p/
Step 5 - Follow a conversation with the Step 6 - Recall four or more critical elements
topic disclosed.
in a message to follow multiple element
directions.
Step 7 – Detect* the sounds of the
Six Sound Test at various
distances.
Step 8 – Locate the direction of
sound if amplified binaurally.
Step 7 - Imitate consonants differing in voiced
vs. unvoiced cues, e.g., [b^] [b^] vs. [p] [p] and
then with vowel variety, [bobo] [pae-pae]
Step 6a - Answer questions about a
story with the topic disclosed.
Step 8 - Alternate consonants varying
Step 6b - Answer questions about a
in place cues, first with varying vowels,
story with the topic disclosed; story is
e.g., /ma-ma/ /no-no/; /go-go/ bi-bi/, etc. teacher-recorded.
Step 9 - Alternate syllables with varying
consonants and same vowel, e.g., [bi],
[di], [ho] [go]
This guide is intended to aid professionals in the beginning stages of
learning an auditory-based approach. As professionals acquire more
experience in auditory teaching, children should progress more rapidly.
The information on this chart was adapted from Judy Simser’s article in the
Volta Review (1993) (** items), from the Auditory Skills Program, New
South Wales Department of School Education, from the Foreworks Auditory
Skills Curriculum (1976, North Hollywood, CA), and from teacher input.
Notes:
* A detection response could include turning head, pointing to ear,
clapping, dropping a toy in a container, etc.
Reference:
Simser, J.I. (1993). Auditory-verbal intervention: Infants and toddlers. Volta
Review 95(3): 217-229.
Step 3b - Identify words in which the final consonants are
the same but the vowels and initial consonants are different,
e.g., food vs. card .
Step 4 - Identify words in which the initial and final
consonants are identical but the vowels/diphthongs are
different, e.g., book vs. back .
Step 7 - Complete known linguistic
messages (open set).
Step 5a - Identify words in which the vowels & final consonants
are identical but the initial consonants differ by three features manner, place of articulation, and voicing, e.g., mouse vs. house .
Step 8 - Follow open set directions and
instructions (disclosed).
Step 5b - Identify words in which the vowels & initial consonants
are identical but the final consonants differ by three features manner, place of articulation, and voicing, e.g., comb vs. coat .
Step 7 - Recall details of a story (topic Step 9 - Recall specific elements in a
disclosed).
sentence by answering questions about an
undisclosed but familiar topic.
Step 6 - Identify words in which the vowels and the final/initial
consonants are identical but the initial/final consonants differ by
two features: (a) manner and place (voicing in common), moat vs.
goat ; (b) manner and voicing (place in common), man vs. pan ; (c)
place and voicing (manner in common), boat vs. coat .
Step 8 - Sequence the events of a
story (topic disclosed).
Step 10 Repeat each word in a sentence exactly.
Step 7a - Identify words in which the vowels and final
consonants are identical but the initial consonants differ by
only one feature - manner of articulation, e.g., ball vs. mall .
Step 9 - Retell a story with the topic
disclosed, recalling all the details in
sequence.
Step 10 - Make identification based
on several related descriptors (open
set).
Step 11 - Follow a conversation of an
undisclosed topic.
Step 11 - Recall specific elements in a
sentence by answering questions on an
undisclosed topic.
Step 12 - Retell a story about an
undisclosed topic, recalling as many
details as possible.
Step 13 - Process information in
noise and at various distances.
Step 14 - Process group
conversations.
a.) predictable sentences “I’m going to the grocery store
to buy cereal and milk.”
b.) less predictable sentences “A woman hit me so I told
her to calm down.”
Step 7b - Identify words in which the vowels and initial
consonants are identical but the final consonants differ by only
one feature - manner of articulation, e.g., cloud vs. clown .
Step 8a - Identify words in which the vowels and final
consonants are identical but the initial consonants differ by
only one feature - voicing, e.g., coat vs. goat .
Step 8b - Identify words in which the vowels and initial
consonants are identical but the final consonants differ by
only one feature - voicing, e.g., bag vs. back .
Step 9a - Identify words in which the vowels and final
consonants are identical but the initial consonants differ by
only one feature - place of articulation, e.g. bun vs. gun .
Step 9b - Identify words in which the vowels and initial
consonants are identical but the final consonants differ by
only one feature- place of articulation, e.g., sheep vs. sheet .
revised: 9/3/10
ALG

Goal is to make more than a year’s progress in a year’s
time.
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
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
Why?
So if a child was two years behind, we would want them to get
through the first year of the ALG, and be started on the second
year of the ALG in just the first year of audiologic rehabilitation.
Years are outlined by color
Remember back to the chart of Auditory Development

We want to work on specific receptive and expressive skills
associated to:

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
Sound Awareness
Phonemes
Discourse
Sentence
Words