PKBI-What Is Auditory Discrimination

8/7/2019 PKBI-What Is Auditory Discrimination

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What Is Auditory Discrimination?

Auditory discrimination refers to the brain's ability to organize and make sense of language sounds. Children withauditory discrimination difficulties might have trouble understanding and developing language skills because their

brains either misinterpret language sounds, or process them too slowl y. Often, these children cannot differentiatebetween similar sounds, or they are unable to recognize language in certain situations.

Language is made up of phonemes. A phoneme is the smallest possible sound in a word, and is not necessarily relatedto spelling. For example, the word "night" has three phonemes: the "n" sound, the "eye" sound, and the "t" sound.When we listen to language, our brains organize the different sounds into meaningful chu nks that we can interpret aswords. This is called phonological awareness.

People with auditory discrimination disorders may appear to be deaf or hard of hearing. They might not respond to

spoken language if there is background noise, or they might understand sounds incorrectly. Problems with auditorydiscrimination are usually related to the brain rather than to the ear itself. It means the person can hear, but he or shehears things "wrong." A doctor can diagnose an auditory discrimination disorder after tests have shown there are nophysical hearing problems.

Children with auditory discrimination disabilities often fall behind in school, particularly in reading and spelling,because they lack the phonological awareness needed to make relationships between sounds and the symbols thatrepresent them. Sometimes they appear to have speech impediments or a stammer because they cannot accuratelyproduce the language sounds they can't hear properly. These children may also be unable to understand a teacher whois not facing them or addressing them directly, or they will ha ve difficulty picking out language sounds if there is any

background noise.

The Wepman's Auditory Discrimination Test (WADT) is an assessment tool that is commonly used to diagnoseauditory processing disorders in young children. In this test, a child is seated so that she can't see the examiner. Theexaminer reads a series of minimal pairs, or words that differ by only one phoneme such as "bit/pit" or "ship/sheep."Some of the pairs of words have no differences, and the child is given a score based on how many pairs she correctlyidentifies as the same or different. Other tests might involve asking a child to repeat words back to an examiner, or saya word back with a sound missing.


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AUDITORY PERCEPTION

y It is particularly true, for the auditory modality, thatthe signal, which carries the message, is transient. It

lasts for only a brief moment in time and is gone.Hence, the speed and efficiency of the processes that

decode the signal are critical.

y Speech is probably the most difficult of the auditorysignals to process. It contains a stream of

multitudinous and rapidly modulated variations.

ySome of these change the meaning a lot, some changeit a little, and some have no effect on the meaning.

y In addition, meanings are being transmittedsimultaneously on several levels including: non

linguistic, phonetic, morphologic syntactic, semantic

and pragmatic. As difficult as it is, we (humans) make

it look easy.

Figure-Ground discrimination is sometimes

referred to as Signal to Noise

Discrimination in the Auditory Modality.

yThere can be little doubt that we have received agenetic inheritance of basic neural networks that

make our amazing auditory perceptual skills at all

possible. And then we spend many years buildingupon and perfecting these networks.

yAuditory perception involves many processes, andsub processes and sub sub processes, all of which are

important.


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yTo discuss them all would require almost taking amajor in Psychology. For now we will examine the

following select group of major processes: Figure-

ground discrimination; Closure; Temporal Resolving

Power, and Memory.

1. Figure (Signal)-Ground (Noise)

Discrimination: We have discussed figure-

ground in generic terms, and have provided

examples for the visual modality.

There are two types of figure-ground task. They arereally opposites ends of a continuum. At one end is an

Aural figure-ground task and at the other is a

Statistical figure ground task.

yAn Aural figure-ground task is one in which thefigure and the ground are unmistakably different. It

never fails, when you are in a class and the instructor

says "Listen carefully because this will be veryimportant" that a loud lawn mower and/or a leaf

blower will pass by the window.

oTo say that it is very difficult to concentrateunder such conditions is to have commented on

an aural figure-ground task. Or worse yet,

someone with a nasal-dripping cold (as

demonstrated in the Notes) sits behind you in

class with much audible sniffling etc.

NOTE: See if you can ignore this ground (noise).


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In an Aural Task, the Signal and the

Noise are different, but in a Statistical

Task, they are similar.

oNeither the lawn mower nor the sniffling wouldbe confused with the speech signal, but they

create a significant figure-ground task for the

brain, which must internally suppress the racket

while interpreting the speech.

yThe Statistical figure-ground task is even morechallenging. This is a listening situation in which the

figure and the ground are very similar.

oAny teacher or parent who has tried to listen totwo or more kids simultaneously telling about

something that happened, will know the

difficulty of this task.

oDuring the second World War in England therewere many instances when planes (many in dire

distress) were returning from missions andrequesting emergency landing instructions.

For children with Figure-ground

processing problems, noises prevent

them from understanding much of what

is said.

oThe tower operators had to listen tosimultaneous voice transmissions over the same

radio band, and make decisions about who was

saying what.


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oSome children (and adults too) have particulardifficulty in discriminating speech or other

sounds in the presence of back ground noises--

even small ones. For them noises are more than

minor annoyances. They are a major cause oflearning disabilities.

oThese individuals are constantly switching theirattention to unimportant sounds such as foot

scraping, light buzzing, whispering, pencils

falling, blowing wind and fans etc. etc. etc.

oHence, they miss most of what they need know,and find listening unrewarding, if not fatiguing.

oConversely, it is possible to improve thisperceptual ability with practice.

oExercises can be created to target soundsembedded in varying degrees of background

noise. These can be both fun and productive in

developing these skills.

oOne clever battery of training exercises wasdeveloped, for example, by the Alameda County

School Department in California. Some excerpts

from this and the Goldman-Fristoe-Woodcock

Test batter are in the Notes.

NOTES: Hear some audiotory figure-ground test and training samples.

2. Auditory Closure. Auditory closure is a

process of filling in the missing pieces of the

figure. Often the noise, (another word for

ground) which accompanies the signal

(another word for figure), actually

obliterates some of it. Quite often it is the


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higher frequencies which are lost. For the

speech signal, this tends to mask many of

the consonant sounds. A person with a high

frequency loss experiences this loss all the

time.

Although closure typically depends upon

learning, its application is often automatic

and unconscious.

oBut for a person with a high frequency hearingloss, low frequency environmental noises often

mask many of the remaining vowel sounds upon

which they depend for important cues. Hence

their hearing loss seems much worse than would

be expected when there is a lot of noise

oIn all of these instances, to obtain the meaning,the brain must internally reconstruct the signal

and fill in the missing parts.

oThis is one form of auditory closure. Sometimes,the closure is so automatic and efficient that we

are hardly aware that some of the consonants are

missing.

y In the notes you will here a list of words with missingconsonants. See if you can understand these words or

tell which consonants are missing.NOTE: Hear an auditory closure sample.


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Auditory Blending involves bringing the

fragments of a word together to obtain

its meaning.

oIt is not only noise, however, that can degrade asignal. Sometimes, the information part of the

message (the figure) is dismembered. For

example, what is this word:

o"c________a________t________a________p________u________l________t"

oYou probably sounded it out in pieces and thenpulled it together in mental closure process.

oThe meaning of the word "was catapulted" intoyour consciousness, and the experience was

relatively rewarding (granted the perks in my

life are probably a little more reserved than for

most students).

oThis type of auditory closure skill has a specialname, "BLENDING", and it plays a major role

in reading.oIf a child has a processing problem in blending,

trying to learn to read using the phonics

approach can be very frustrating and

unrewarding..

Many fun games and activities can be

created to exerciseB

lending and otherperceptual skills.

oI have found many non readers at the JuniorHigh level who still cannot blend sounds. In some

cases it's a persistent perceptual deficit. In others


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it is a psychological overlay (i.e., history of

failure) that discourages them from even trying.

oWhile I don't advocate formal readinginstruction for preschool and kindergartners, I

do encourage fun activities which involvepractice in closure tasks.

oFor very young children, Piaget suggestedpartially hiding objects. He, of course, was

talking about teaching object permanence to

babies, but the principal is the same.

oFor example, an activity might involve partiallyhiding three different dolls under pillows and

asking the child to find a particular one. Of

course, that was the visual modality and we are

talking auditory here. Many four year old

children love to guess the names of words given

to them in peices, like "potat.......to." With my

four year old, at first we made two choice games.

I would say, "toma.......to;" and then she would

guess whether it was "tomato" or "pillow." The

success rate was high here, and that is very

important. Later we would just practice straight

blending, although with syllables and not

phonemes. In giving me a hint about a birthday

present I was getting, my four year old said they

were fuzzy and warm, went on the feet and

started with the sounds..."slip...." Because, I was

a little slow in the closure, she after about 30seconds added the ..."er." The notes below have

some test & training examples in blending for

older children.

NOTES: Here is some training ideas for Auditory Blending


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Auditory Closure is needed to correct

the distortions of speech.

oSometimes, the speech signal is neitherembedded in a distracting ground nordisassembled. But it may, nevertheless, require

closure, because it is distorted.

oThe most common and important examples ofthis are cases involving a foreign dialect.

oMany highly talented people come to anothercountry and contribute much to the new

community. Even though they may speak thenew language, however, communication often

remains a serious problem because of their

foreign accent.

oCan you imagine the stress that could be createdfor a nurse (not to mention the patient) at an

operating table if she wasn't sure what

instrument the doctor was asking for, because of

his accent! In the notes is a similar, if notscientific example.

NOTES: Can you understand this accent?

3.Temporal Resolving Power is the ability

to handles rapid sequences of sounds.

yTemporal Resolving Power: Most auditory stimulicome in sequences over time. Typically, the successionof events is very rapid. There is, however, a limit to

the ability of the perceptual system to discriminate

the discreteness of successive stimuli as they come

closer together in time. For example, if two clicks


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occur far enough apart in time, you would definitely

hear two clicks...

When two successive sounds come too

close together, some individuals mayhear only one.

oIf they were even closer in time, you might stillhear two clicks, although someone with a brain

dysfunction might only hear one.

oBut, if they were even closer, although there willstill be two clicks, we all would eventually come

to the point where we would perceive only one.

Eventually a threshold is reached where

everyone hears just one of two rapidly

presented sounds.


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yThis is interesting (possibly), but does it have anyrelevance to speech and language, you may ask. Yes

most definitely. The ability to hear even the

occurrence of some consonants (which occur as

sounds in quick succession with vowels) depends on

this ability. The principle is the same fordistinguishing the order of rapidly presented series of

different stimuli.

y Speech, itself, is nothing but sequences of differentstimuli (phonemes), and perceiving their order is

more than half of the decoding game. If the phonemes

are far enough apart in time, you can perceive their

order.

Perceiving the order of successive

speech sounds depends on their speed of

delivery.

y Speech, itself, is nothing but sequences of differentstimuli (phonemes), and perceiving their order is half

of the decoding game. If the phonemes are far enoughapart in time, you can perceive their order.


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yAs they get closer together in time you may stillperceive their order...

...but for someone with lesser perceptual processing

power...

Some individuals may not be able to

perceive the order if they come too fast.

y ...such as young children with immature neuralnetworks; individuals with brain dysfunction or much

older folk like me (with both thinning hair and brain

cells) may become confused.

yNow we don't know whether the order was CAT orTAC or ACT. In speech, of course, it makes a bigdifference.


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Understanding the order of sounds is

also critical for decoding morphological

structure and meaning of words.

yAs you can imagine, the possible combinationsincrease wildly. Was the word SCAT, TASC, TACS,CATS, etc. etc.? What a confusing task for someone

with weak Temporal Resolving Power! Notice,

however, that not only the meaning of the word is at

risk, but also the meaning that may come through the

structure of the bound morphemes!

"Fast Forward" is a computer program

that slows down the presentation of

consonants.

y If a child doesn't perceive the "s" and other boundmorphemes on the ends of words, how will he/she

learn the principles of grammar, such as plurals and

possessives and such? This can impact negatively

upon children's language development, reading skillsand academic achievement.

yThe problem of sequencing for some children hasbeen addressed in recent years by a computerized

program called "Fast Forward."


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yThis program is produced and marketed by theScientific Learning Corporation in Berkeley,

California. In this program, consonants are

prolonged to provide greater time for the child to

process and recognize the order of phonemes. Thenotes below provide respectively, the Company's Web

Page, information on Fast Forward, a discussion and

a Sample movie.

NOTES: Fast Forward's Web Page

NOTES: Introduction to Fast Forward

NOTES: See how to learn to use Fast

Forward

NOTES: See and hear a brief view of fast

forward.

Games and listening oriented activities

will improve Temporal Resolving Power.yOf course, providing listening opportunities for very

young children would seem highly advisable to

nurture the development of the neurological infra

structure that will enable good listening skills for the

future.

yThis can take the general form of multiple dailyreadings (initially nursery rhymes which providerhythm, intonation and rhyming. This should be start

very early.

y I would consider from one week after birth to 14years, although you can begin to think of broadening


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the scope from nursery rhymes after two and a half

years.

yLater, training can take a more structured form likelistening centers with games and exercises forchildren. In the notes are some exercises for school

age children.

NOTES: Hear some sequencing examples.

The localization of a sound depends also

on Temporal Resolving Power.

y Sound Localization: Because we may not consciouslyperceive the order, or even the discreteness of two

very close successive stimuli, it does not mean that

our perceptual system has lost track of the time

intervals involved.

yWe actually are still processing them, but at a

different level and in a different way.yTake for example a sound that comes to us from the

extreme right side.

yThe sound wave first reaches our right ear, and thenmust travel the width of our face to reach the left.

There is a brief time interval involved between the

stimulation of each ear.

yThis is maintained as the sound continues in the formof a difference in phase between the input of each ear.

But, the time interval is too brief for us to perceive

two sounds.


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Sound Localization (like stereopsis)

requires two normal transducers (ears) .

yThe brain is still actually receiving two sounds, andprocesses the time difference between each to produce

the illusion of a sound localized in space!

yAs the sound source moves toward our center (frontor rear) the time differential between the ears

decreases and the sound appears to move towards the

center. We are, at any point in time, only aware of thelocation of the sound in a single horizontal plane to

the right or left.

y If it is a brief sound, we can't really ascertain whetherits source is to our front or back, or above or below

us.

yBut if the sound persists, we will without realizing itmake small adjustments of our head (ears) to sampleseveral different planes and quickly zero in on the

sound source.

y For the most part it takes two ears to perceivelocation of the source of a sound.

The sound localization process

facilitates figure-ground discrimination.

yThere are some sophisticated, if not minimal cues forlocation that do come from a single ear in the form of

the resonance created in the Pinna.


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yThis is discussed briefly with some references foranyone who is interested, in the notes below.

yThere is one more contribution of TemporalResolving Power, which I would like to point out.

y It is the interaction of sound localization with figure-ground discrimination.

yYou might have noticed, if you have ever taped alecture and listened to it later, that you were more

aware of all the background noises than you were in

the actual classroom.

yThis is because in the classroom, you were able to usesound localization to identify noise sources.

NOTES: Information on sound localization.

NOTES: More information on Sound

Localization.

A person with only one good ear will

learn language normally, but will have

to work harder to understand speech in

a noisy environment.

yWhen you listened to the tape, however, the soundsource was all from one direction and figure-ground

discrimination becomes a more difficult task.

yHence, a person with one good ear may hear soundsas loudly and clearly as anyone else, but will

experience more confusion and fatigue in a noisy

environment.


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yThe same is true for someone with a hearing aid,which has only one microphone to pick up the sound

signals.

4. Auditory Memory:

yMemory, of course, is a major component of ourneurological armament. It is a massive process that is

involved in almost all other cognitive skills. Scientists

spend their lives studying it, and still we don't know

the basic mechanisms involved. But there is much

information we do have, and we will look at some of

this later.

Because the speech signal is discursive

and transient, memory must retain it

until decoding takes place.

yBut for now we must acknowledge the role of memory

specifically in the auditory process. Two things arecritical in audition. The auditory stimulus is

transient, and the message is discursive. That means

the signal is strung out in time. It doesn't hang

around long enough for us to experience the entire

message in one "sitting," like we can when we observe

a picture.

y In audition, it remains for the processes of memory tohold on to the pieces of the stimulus that have faded,

so that we can deal with them as if we had the whole.

Note that I said processes (plural), because memory

(like language) is a system of many sub processes.


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yOf the many memory sub processes, we will mentiontwo for now: Short-Term and Long-Term memory.

y Short-Term Memory, is the ability to hold on to thesignal for short periods of time--from milliseconds to

hours. It is not, however, a single process but a groupof sub sub processes: Sensory, Perceptualand Wrote

Memory.

oSensory short-term memory, pertains more tothe action of the transducer. In many respects it

is the counter part of after imagery in the visual

but with a different purpose.

Sensory short term memory holds the imagefrom the transducer long enough for us to

recognize is structure.

Without the after glow on a radar screen,for example, patterns would be difficult to

discern. Sensory short-term memory

performs the same purpose. It enables us to

recognize sounds patterns, like phonemes.

oPerceptual short term memory, relates to ourability to retain strings of words while the brain

decodes their phonological, morphological,

syntactical, semantic and pragmatic significance.

This is truly an amazing process!

People often talk to us in long complicatedsentences. The meaning of any sentence can

only be obtained from an analysis of the

interrelation of all the words taken as a

whole.

The sentence must also be analyzed in termsof a sentence that may have occurred earlier

in the conversation.


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There may be 20 to 50 words in a sentence.We must hold on to the words, extract the

meaning, and do it fast enough to be ready

to receive the next sentence which comes

right on it(tm)s heels, and the next and thenext.

What makes it truly amazing is thattypically we are limited to approximately 7

bits of information for this short term

memory process. We obviously do more by

using various organizational strategies.

One important strategies is expectancy. It'sinteresting that most computers have some

of this now in the form of word prediction.

You start to type something and the word

appears before you finish.

Context and and particularly grammar areimportant features of expectancy which

broaden our input capacity.

For a child (or adult) with severely limitedshort term memory (say 4 or less bits in

information) and with few strategies to rely

on, (e.g., poor grammar and/or a dearth of

life experiences) decoding an oral sentence

can be a significant problem.

A child with a very restricted short-

term memory may have difficultyunderstanding long sentences.

I actually experienced a similar situatiion inLatin II class. I did well with Caesar who


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came, who saw and who conquered Gaul;

and wrote about it in short sentences.

But when I enrolled in Latin III (buoyed bymy apparent success in Latin II) I was in for

a "Custer's Last Stand" experience. Herewe read the works of Cicero who never

wrote a short sentence, I am sure, under two

pages long. I could never get a complete

sentence into my all at once head.

By the time I got to the verb phrase throughall the relative clauses etc., I had totally

forgotten what the noun phrase had been,

not to mention the information that was in

all the subordinate and embedded clauses.

My short term memory, I believe, wouldhave to have been 21 bits to get the whole

Latin Cicarian sentence.

Ceasar was easier to understand

than Cicero (at least for me) becausethe latter used very long sentences


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We use Wrote Memory to retain

information long enough to be processed

into Long-Term memory.

Unlike perceptual short term memory whichlasts for fractions of a second, this process

can last for hours.

It is also useful for holding on toinformation long enough to convert it into

long term memory, but that is a later

discussion.

There is much that we can do with ouryoung children to develop perceptual andwrote memory skills.

Reading to the child (the infant too) is amajor positive step. Putting TV in the

locked closet is another.

Suffice it to say that the brain waves of aperson watching the typical TV shows are

similar to a person who is asleep. I see

limited brain growth there--and a whole lotof wasted time where growth could have

taken place..

To be honest, I believe there are a few TVshows which do have merit.

There are many activities that

will improve the short-termmemory process.

I have already mentioned "Mr. Rogers'Neighborhood". As being excellent for a

number of reasons For this show I would let


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the child in the closet, with the TV, but not

until he's three years old and then for no

more than 1/2 an hour a day. I would ban all

shows with cartoons.

Almost any children's game is beneficial fordeveloping short term memory. Later on

chess is outstanding for this purpose.

Theater group play acting is anotherexcellent source of short term memory

practice.

Equally important are activities likelearning to recite poems, starting with

nursery rhymes and continuing, much later

on, of course, with things like the

Declaration of Independence, and world

class poetry.

Not only do these activities providevocabulary and concepts, but they, more

importantly I think, facilitate the neural

infra structure for short term memory

which will serve the child for a life time. The

rule of thumb, here, is to involve the child as

oLong Term Memory: Long term memory is, ofcourse, indispensable in any decoding task.

Without it, no meaning can be attributed to the

percept.

We have discussed problems in this area

under Aphasia and Agnosia and we willhave more to say about this topic when we

examine the cognitive processes of memory.

For now, lets return to the main menu andexamine some Behavioral or Learned


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influences in the perceptual process:

Attention and Expectancies.

Documents

PKBI-What Is Auditory Discrimination