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AUDITORY TRAINING
I. Room Acoustics
Noise levels are measured with a ______________.
There are 3 weightings on the meter which vary in the amount of ___ frequency reduction.
The weighting which is most like the response of the ear is the____scale.
The primary energy in background noise is ____ frequency.
Sources of noise in the classroom include:
InternalInternal and External
Sources
furniture
A/C or heater
kids talking
equipment in room
lights
COMD students snoring
TA lecture
External
gym
music room
hallway
road
airport
machinery
Optimal Noise Level
Optimal noise level
for H of H class = _____ dBA,
yet the typical level is = _____dBA
Optimal S/N Ratio
The optimal S/N ratio= _______,
while the typical S/N ratio= 0 to +5
Big Important Empirical Stuff
__________ study mentioned in readings showed effects of noise and reverberation on speech recognition scores with Normal Hearing and
Hard of Hearing Children 8-12 years old .
In a soundbooth:
No Noise, Little Reverberation
Norm= 95% H of H= ___%
Norm= 95% H of H= ___%
With RT= .4
Norm H of H
S/N Ratio of +12: 83% 60%
S/N Ratio of 0: 48% 28%
With RT= ____
Norm H of H
S/N Ratio of +12: 70% ___%
S/N Ratio of 0: 30% ___%
B. Reverberation
Sound in a room travels until it reaches a partition or room barrier and then it is _______.
The level of reflection depends on the __________ of the sound by the surface.
The________ the absorption, the less sound is reflected.
General Definition
Reverberation time (RT) reflects the decay of energy of a sound after its ______.
Specific Definition
The RT is the time for the SPL to decrease by ____ dB after the sound stops.
Two Important Points to Remember!
As volume of a room increases, the RT ________.
As absorption of a room increases, RT ________.
Typical Values of RT
auditoriums - ___ secs
classrooms -___secs
Ideally, classrooms for the hearing-impaired would have reverberation time close to ___.
The effect of reverberation on speech recognition is a _______ of temporal cues in speech. The silent intervals between phrases and syllables are filled in with reflected energy.
Reverberation may also cause greater masking of _______ consonants following intense vowels.
Measurement of RT using
Reverberation Meters
&
Formulas
To determine reverberation, one may use a reverberation meter or calculate the RT using measures of room volume and absorption __________ of room surfaces.
Measurement with RT Meter
Use frequency specific stimuli (noise burst)
Present loud burst in a room and the meter measures decay.
Measure at several speech frequencies
500 Hz
1000 Hz
2000Hz
Performed across frequencies because RT has a tendency to be _________ at low freq. and shorter at higher freq.
Take the _________of measurement over range of frequencies tested.
Average gives composite number for RT, easy to use and remember.
Measurement Using Formula
A formula for reverberation time is:
RT = (0.05V)/A
RT = reverberation time in seconds
V =________ of the room in cubic feet
A = total room absorption coefficient in sabins
0.05 = constant
Calculation Using Formula
RT = (0.05 V)/A
Volume = length x width x height times 0.05
A = sum of [avg absorption coefficients (AC) x area] for each surface in the room (floor, walls, etc)
AC for each surface are found by taking the _________ of the AC at 500, 1000, & 2000 Hz of the material in question (table 5-2 pp104)
Calculation Example
Calculation Example
RT = (0.05 V)/A
Volume of room 7x16x24 = 2688 cubic ft
2688 cubic ft = V
(0.05 V) = 134.4
Calculation Example
RT = (0.05 V)/A
A = Sum of sabins for all surfaces
Sabin for a surface = avg AC (table 5-2 pp104) x area for each surface (wall, floor, etc)
Side Wall Sabins
Left side wall area 7 x 24 = 168
Right side wall area 7 x 24 = 168
Absorption Coefficient values for plaster on concrete at .5, 1, 2 kHz from table
.07, .05, .05, avg = .06
Left side sabins = area x AC = 168 x .06 = 10.08 sabins
Right side sabins = area x AC = 168 x .06 = 10.08 sabins
Front Back Wall Sabins
Front wall area 7 x 16 = 112
Back wall area 7 x 16 = 112
Absorption Coefficient values for plaster on concrete at .5, 1, 2 kHz from table
.07, .05, .05, avg = .06
Front wall sabins = area x AC = 112 x .06 = 6.72 sabins
Back wall sabins = area x AC = 112 x .06 = 6.72 sabins
Ceiling Sabins
Ceiling area 24 x 16 = 384
Absorption Coefficient values for plaster on lath at .5, 1, 2 kHz from table
.06, .05, .04, avg = .05
Ceiling sabins = area x AC = 384 x .05 = 19.2 sabins
Floor Sabins
Floor area 24 x 16 = 384
Absorption Coefficient values for wood parquet on concrete at .5, 1, 2 kHz from table
.07, .06, .06, avg = .06
Floor sabins = area x AC = 384 x .06 = 23.04 sabins
Calculation Example
RT = (0.05 V)/A
Area AC Avg Sabins
R. Wall 168 x .06 10.08
L. Wall 168 x .06 10.08
Front Wall 112 x .06 6.72
Back Wall 112 x .06 6.72
Floor 384 x .06 23.04
Ceiling 384 x .05 19.2
Total A 75.84
Calculation Example
RT = (0.05 V)/A
RT = (0.05 V)/A
RT = 134.4 / 75.84
RT = 1.77
Very reverberant room!
Calculation Example
RT = (0.05 V)/A
Could change floor & ceiling to acoustical tile & carpet to increase sabins
Calculation Example
RT = (0.05 V)/A
Volume of room 7x16x24 = 2688 cubic ft
2688 cubic ft = V
(0.05 V) = 134.4
Side Wall Sabins
Left side wall area 7 x 24 = 168
Right side wall area 7 x 24 = 168
Absorption Coefficient values for plaster on concrete at .5, 1, 2 kHz from table
.07, .05, .05, avg = .06
Left side sabins = area x AC = 168 x .06 = 10.08 sabins
Right side sabins = area x AC = 168 x .06 = 10.08 sabins
Front Back Wall Sabins
Front wall area 7 x 16 = 112
Back wall area 7 x 16 = 112
Absorption Coefficient values for plaster on concrete at .5, 1, 2 kHz from table
.07, .05, .05, avg = .06
Front wall sabins = area x AC = 112 x .06 = 6.72 sabins
Back wall sabins = area x AC = 112 x .06 = 6.72 sabins
Floor Sabins
Floor area 24 x 16 = 384
Absorption Coefficient values for carpet at .5, 1, 2 kHz from table
.14, .37, .60, avg = .37
Floor sabins = area x AC = 384 x .37 = 142.08 sabins
Ceiling Sabins
Ceiling area 24 x 16 = 384
Absorption Coefficient values for hanging acoustical tile at .5, 1, 2 kHz from table
.50, .69, .79, avg = .66
Ceiling sabins = area x AC = 384 x .66 = 253.44 sabins
Calculation Example
RT = (0.05 V)/A
Area AC Avg Sabins
R. Wall 168 x .06 10.08
L. Wall 168 x .06 10.08
Front Wall 112 x .06 6.72
Back Wall 112 x .06 6.72
Floor 384 x .06 23.04
Ceiling 384 x .05 19.2
Total A 75.84
Calculation Example
RT = (0.05 V)/A
Area AC Avg Sabins
R. Wall 168 x .06 10.08
L. Wall 168 x .06 10.08
Front Wall 112 x .06 6.72
Back Wall 112 x .06 6.72
Floor 384 x .37 142.08
Ceiling 384 x .66 253.44
Total A 429.12
Calculation Example
RT = (0.05 V)/A
RT = (0.05 V)/A
RT = 134.4 / 429.12
RT = 0.31
Ah, Much Better
C. Distance
In general, sound decreases w/ increased distance.
With every doubling of distance
(w/ 0 RT) there's a ____ decrease
in SPL. (_______Square Law)
Near /Far Fields
Near Field .1 -.7 meters from speaker
Far Field ____ meters from speaker
Inverse ______ law holds for near field
(doubling of distance decreases 6 dB)
Inverse square law does not hold for far field.
(SPL approximately the same in far field for a broad band noise)
Near/Far Fields
Beacuse of ______ Field effects you do not want to hold FM mic six inches from speaker for behavioral testing.
Better to measure at________ meter. Less variability in signal level due to movements of microphones.
II. Speech Acoustics and Perception
A. Short Term Characteristics
B. Long Term Characteristics
A. Short Term Characteristics
Vowels
Consonants
Vowels.......
Have unrestricted flow of air from larynx.
The vibratory motion from vocal folds is shaped
by the vocal tract.
The first formant peak corresponds to ..........
jaw opening/height.
The second formant peak corresponds to........
front/back tongue placement.
The plot of F1 vs F2 with the three point vowels /?/, /?/, and /?/ represented is a convenient way to remember the relative relationships among vowel formants.
F1 is always higher in intensity and lower in Frequency than F2.
Consonants
Have an obstruction of air flow.
Acoustic characteristics are determined by position and timing of articulators.
Place of articulation is cued by frequency changes over time. These changes occur in the high-frequency region.
In the case of stop consonants, these changes are known as F2 transitions.
The back stops are represented by falling transitions while the front stops are represented by rising transitions.
Manner of articulation is cued by both frequency and temporal changes.
For example nasality is cued by ???-frequency energy, while fricatives are cued by ????-frequency energy.
Voicing is cued by broad spectral energy and some temporal information.
There is a relative intense cue in the low frequencies because of the fundamental frequency.
B. Long Term Characteristics
The long term speech spectrum represents the average of speech over time. There is a peak of energy at ???? Hz.
If inverted and plotted on an audiogram, there is resemblance to what is known as the ?????
The average SPL of speech is at 1 meter is 65dB SPL.
The range of intensities in speech, i.e. the dynamic range, is 30 dB.
The least intense sound is the /?/ and the most intense is the /?/.
95% of speech power is below 1000 Hz, while 95% of speech
intelligibility is above 1000 Hz.
3 Ways to Represent Speech
Waveform-- Intensity (dBSPL) x Time (ms)
Spectrum-- Intensity
(dB SPL) x Freq. (Hz)
Spectogram-- Frequency (Hz) x time (ms)
Speech Demonstration
III. Hierarchy of Auditory Skills
A. Hierarchy of Skills- By Norman Erber
Detection-
Identifying the presence of sound through a reflexive response or a purposeful change in behavior (i.e.clapping, sucking, raise hand, yes/no)
Discrimination-
Recognizing that a change has occurred in frequency, intensity, or temporal information.
At least 3 paradigms
1) Responding to a change in an auditory trace by an intrusive sound (bababagaga)
2) Choosing one in an oddity paradigm (bagaba)
3) Labeling a pair of sounds same or different (ba ba or ba ga)
Discrimination can be measured even in infants through the use of habituation paradigms where the infant signals discrimination by dishabituation.
That is, heartrate or sucking, is measured in response to an ongoing stimulus, and over time the sound is less interesting and a decline in rate is observed.
Dishabituation is an increase in rate that corresponds to a change in the sound.
Identification-
Association of an auditory trace with past experience by
pointing to a picture
pointing to an object
or imitating.
Comprehension-
Associate auditory trace with past experience and relate it to other stored information by answering questions about stories, following directions, etc.
To make each of these levels more complex one could add
open response set, increase length of stimulus, noise, distance, sequencing, memory, etc.
B. Model of Perception
EAR
HEAR
EARHEAR
Expectancy Set-
HI children have to be taught the sets and how to monitor the conversation to be sure one is in the right set.
Attending-
Very tiring for HI.
Need frequent breaks.
Reception-
Affected by the hearing loss. Only getting partial information.
Trial & Check-
HI spend more time here trying to get a match. Meanwhile the conversation goes on and they may have missed more critical information.
Perception-
The final stage, when the auditory trace is associated with past experience and additional associations are made if possible.
C. Theorems of Perception
We perceive in PATTERNS of stimuli.
The consistency of perception implies some underlying ORGANIZATIONAL pattern.
We tend to perceive INCOMPLETE figures and complete.
Familiarity FACILITATES perception.
IV. Assessment and Intervention
A. Assessment of Auditory Skills
Rationale to make educational decisions about IEP or three year review; to determine ability to use auditory cues; and to determine ability to use spectral cues.
Should be an Interdisciplinary Effort-
1. Audiologist- checks unaided and aided functioning
2. Speech Pathologist- oral/peripheral exam; speech and language evaluation
3. Deaf Educator- Assesses academic skills and provides ideas for integrating AT into curriculum
Items Needed for an Auditory Training Program-
tape recorder tape of _____________ sounds pictures of ______ sound level meter; reverb meter unaided and aided audiogram HA test equipment controlled ________ environment _____ makers (clackers, drums, bells, whistles, xylophone, etc.)
Informal Assessment Tools-
For infants- _________ and____ to sound
(look for startle, localization, attending, or some other behavioral response indicating awareness).
Ling 6 sound speech test-(all ages)
Sounds are: a, i, u, sh, s, m
If child has unaided hearing to 1kHz, then with amplification we’d expect them to detect= __, __, __, __
If hearing to 2kHz, we’d expect detection of ______, m, and sh
If hearing to 4 KHz, we’d expect detection of all sounds.
GASP- Glendonald Auditory Screening Procedure-(3-6 yrs)
1. Phoneme detection-__ vowels, __ cons. 2. Word identification-__ words, _ stress patterns 3. Sentence Comprehension-10 sentences
DASL- Developmental Approach to Successful Listening- (2-10yrs)
1. _____ awareness (includes care & use of the hearing aid)
2. ________ listening (includes listening to their own voice and discrim of supra segmentals and iden of vowels/cons)
3. auditory comprehension (includes discrim of stereotypic messages)
SERT- Sound Effects Recognition Test- (3-6 yrs)
Identify environmental sounds- 3 lists of 10 sounds (sounds played from cassette tape and identifiedby pointing to one of four pictures)
Formal Assessment Tools-
Have standardized administration procedures Have normative data
ESP-Early Speech Perception Test-(3-6 yrs)
Two versions: Standard (uses ________) and Low-verbal (uses _______) Standard Version:Pattern Perception Word-spondee identification Word-monosyllabic identificationLow-verbal Version:
_______ Perception Training
Pattern Perception Test
Word ______________ Test
TAC- Test of Auditory Comprehension- (4-17 yrs)
Has associated training curriculum Has ten subtests Must use ___ to set level of tapeMust have minimal background noise
Ceiling is when child fails __
consecutive subtests
10 tests on the TAC include:
Tests #1-3: Suprasegmental elements
Tests #4-6: Identification and memory, sequencing, critical elements
Tests #7-8: Comprehension Abilities
Tests #9-10: Comprehsion with Masking (figure ground)
B. Intervention
Components of Effective AT Program-
1. Good consistent amplification and monitoring2. Closely related to cognitive and linguistic growth of child
3. Individual needs explored
4. Provide optimum acoustic conditions
5. Early intervention- birth to 3 yrs
6. Involvement of ______
Approaches to Auditory Training-
Important to integrate AT throughout the day.
Naturalistic AT Approach
Integrate AT into all ______ activities but.....
cover mouth, look other way,or create background noise
Moderately Structured AT Approach
Vocabulary and activities pre-determined but no specific drills on skills.
Structured AT Approach
Direct ______ on specific stimuli that may or may not relate to other activities in the curriculum.
Goals and Objectives
Find level of functioning for child and write goals and objectives. Have observable ________, _____, and _______ for success
Types of objectives: (mini goals)
1. ___________- initial teaching of a new skill
2. __________/____________- increase accuracy
3. ______________- integrate info into life
Auditory Training Curricula
ASIPS- Auditory Skills Instructional Program System
Three areas:
awareness,
________ identification,
________ comprehension
DASL- Developmental Approach to Successful Listening
Three areas:
awareness,
________ identification,
________ comprehension
Although skills are hierarchical, can move ahead prior to complete mastery
Begin with live voice close to HA, then increase distance
SKI-HI- Early intervention of HI infants (birth-6 mos.)
Activities to be done at home
Parent advisors train parents in these areas:
Hearing Aid useParent child communication
Child development
_________ skills
Speech & Language
SKI-HI- Early intervention of HI
infants (birth-6 mos.)Comprehensive curriculum addressing entire program
_________ servicesdirect service
administrative services
INSITE- In home, sensory intervention, training program
Parent centered for any handicap. To be taught by non-professionals Sections include:
parent training, communication, and developmental skills John Tracy Correspondence Course
Course-Sequential lessons to be done by parents Separate courses for
deaf/blind, _______, versions in Spanish.