Normal Speech and Language Development: An ...

Normal Speech and Language Development: An Overview James Coplan Pediatr. Rev. 1995;16;91-100 DOI: 10.1542/pir.16-3-91

The online version of this article, along with updated information and services, is located on the World Wide Web at: http://pedsinreview.aappublications.org

Pediatrics in Review is the official journal of the American Academy of Pediatrics. A monthly publication, it has been published continuously since 1979. Pediatrics in Review is owned, published, and trademarked by the American Academy of Pediatrics, 141 Northwest Point Boulevard, Elk Grove Village, Illinois, 60007. Copyright © 1995 by the American Academy of Pediatrics. All rights reserved. Print ISSN: 0191-9601. Online ISSN: 1526-3347.

: Normal Speech An Overview James

Coplan,

FOCUS

and

QUESTIONS

are speech and language defined and related? 2. How are the developmental sequences In the acquisition of speech and language modified by deafness or hearing disabIlity, developmental language disorders, mental retardation, autism, or sociocultural factors? 3. What findings in an infant or child indicate a need for audiologic examination? 4. How are disorders of speech and

best managed?

language

Development:

MD*

1. How

5.

Language

How do disorders of speech and language differ as to prognosis?

regardless of the language spoken by their adult caretakers. The earliest of these utterances is cooing, which consists of musical, open vowel sounds. Cooing should be well established within the first 4 to 6 weeks of life. This is followed in the first few months of life by bilabial sounds: blowing bubbles or the “raspberry.” By 5 months, laughing and a variety of monosyllables appear, such as “ba” or “ga” Between 6 and 8 months, infants produce polysyllabic babbling, which consists of the same syllable repeated over and over: “lalalalala,” ‘mamamamama,” ‘dadadadada,’ and so forth. During the latter half of the first year of life, infants begin to restrict their phonemic repertoire to coincide with the speech sounds of their adult caretakers. By 9 months, infants sporadically produce the truncated utterances “mama” or “dada” without comprehension of the meaning that adults have attached to these sounds. By 10 months of age, infants produce these utterances spontaneously and consistently to label the appropriate parent. By I 2 months, infants have acquired one or two words other than ‘mama, or ‘dada,’ or the names of other family members. Infants also will imitate words when presented by an adult in a stimulus-driven fashion. For example, the adult may hold up a ball and say, “Say ‘ball’ ! ‘Ball’!” Although the infant may repeat the adult’s utterance, this does not qualify as a word in the infant’s vocabulary because he or she is not producing it spontaneously. Vocabulary growth velocity accelerates steadily during the second year of life, starting at a rate of approximately one new word per week at 1 2 months of age and attaining a rate of one or more new words per day by 24 months of age. By 18 to 20 months, a toddler should be using a minimum of 20 words; the typical 24-month-old has a vocabulary of at least 50 words. Early during the second year of life most toddlers produce jargon. Jargon consists of strings of different sounds (as op‘

‘

Normal Language

Speech and Development

Language consists of any symbol system for the storage and exchange of information. It commonly is described in terms of auditory expressive and receptive ability (speech and listening comprehension, respectively). However, language also is conveyed visually. Normal infants attend to gestures and initiate various gestures to make their needs known; visual language development in deaf infants exposed to a formal sign system, such as American Sign Language (ASL), parallels the stages of oral language development in hearing infants;’ and reading and writing are obvious manifestations of visual language in older children and adults. Precursors to auditory and visual language are readily observable from earliest infancy. Because these precursors lack symbolic value, they are termed prelinguistic. AUDITORY LANGUAGE

Human sequence *Associate

EXPRESSIVE

infants

produce

a uniform

of prelinguistic Professor

Training

in Child University of New Center, Syracuse,

utterances,

of Pediatrics,

Director

in Review

Vol.

of

State

Development, York Health NY.

Science

Dr. Coplan also is affiliated with publishers of the Early Language Scale, of which he is the author.

Pediatrics

ARTICLE

16

PRO-ED, Milestone

No. 3

March

‘

1995

‘

‘ ‘

‘

‘

posed to the 9-month-old’s repetition of the same sound over and over), with rising and falling speech-like inflection. Parents may remark that their child seems to be ‘speaking a foreign language.’ The child’s jargon frequently will contain embedded words ( ‘lamanagabanadaddv. manabaganamommy, etc). The child is practicing the inflection patterns of speech with this jargon, referred to as prosody. By 24 months of age, toddlers are producing two-word phrases. These consist of spontaneous, novel combinations: ‘Want cookie!’ ‘Me down!’ and so forth. Children may memorize phrases such as “All gone,” but these are not novel combinations devised by the child. Jargon wanes and disappears rapidly around the time the child makes the transition from single words to two-word phrases. Pronouns appear in the second year of life, at first nonspecifically (ie, the child may reverse ‘me’ and ‘you’ ) and then specifically (‘ ‘me’ always referring to the speaker, and “you” referring to the listener). Vocabulary growth velocity continues to accelerate during the third year of life, ultimately reaching a rate of several new words per day. This increase in growth velocity is accompanied by a commensurate increase in vocabulary size; if a 30-month-old’s vocabulary is small enough for the parent to count accurately (90 dB) loss. The prevalence of permanent, partial hearing loss (eg, bilateral moderate loss, unilateral loss) is unknown. but probably is in the range of three to ten children per thousand. Etiologic factors are the same as for children who have bilateral severe-to-profound loss. Otitis media with effusion (OME) causes transient, mild-to-moderate hearing loss. Approximately 15% of infants experience 90 or more days of OME in the first year of life. Developmental language disorders (DLD) have been reported with increased frequency among such “otitis-prone” infants,4 but the attack rate for DLD specifically attributable to OME is unknown. ‘

RETARDATION

ing below -5 SD are considered to be profoundly mentally retarded. Most mentally retarded children are mildly retarded, and most of these are normal biologically: their mild MR reflects polygenic endowment for intelligence rather than any pathologic process. A lower limit for polygenic determination of intelligence probably exists, however, somewhere between -2 and -3 SD. Therefore, any child who has an IQ below 55 (ie, 3 SD below the population mean of 100) should be assumed to have an underlying pathologic process as the source for his or her MR. Most individuals demonstrate intellectual abilities very similar to those of their parents and siblings. Therefore, if a child’s IQ falls >3 SD below the estimated mean IQ of the other members of his or her nuclear family, an organic disability also should be suspected, even though the absolute value of the child’s IQ may be in the 60s or 70s.

Three percent of children are mentally retarded (Table I ); all children who are mentally retarded are Ianguage-delayed. Mental retardation (MR) is defined as significantly subaverage general intellectual function plus delayed adaptive skills, arising in the first 5 years of life. Adaptive skills include self-feeding, selfgrooming, and self-dressing. General intellectual function is determined by an age-appropriate standardized test that measures problem-solving and language abilities: ‘significantly subaverage’ is defined as more than 2 standard deviations (SD) below the mean. “Mild” MR is defined as -2 to -3 SD. Because intelligence tests are standardized to a mean score of 100, with I SD equaling 15 points, mild MR is equivalent to an intelligence quotient (IQ) of 69 to 55. Moderate MR -3 to -4 SD (IQ 54 to 40), severe MR -4 to -5 SD (IQ 39 to 25), and persons scor-

‘

-

‘

‘

TABLE

2. Indications

for

Audiologic

Evaluation

Neonatal Intensive Care Birthweight < I 500 g Birthweight > 1500 g if complicated by any of the following: Prolonged neonatal depression (Apgar score 0-3 at 5 mm; no spontaneous persisting to 2 h of age) Hyperbilirubinemia at level exceeding indication for exchange transfusion Mechanical ventilation for > 10 d

Congenital

infection

toxoplasmosis,

with agents

known

or suspected

of causing

hearing

respiration

loss

by

(cytomegalovirus,

10 mm;

rubella,

hypotonia

syphilis,

herpes)

Anomalies Mesodermal: Abnormalities of first or second branchial arch (auricles, mandible) Ectodermal: Abnormalities of neural crest (eg, iris heterochromia, albinism, piebaldism) Presence of syndrome known to be associated with hearing loss (eg, Usher syndrome, Family

history

Bacterial

of congenital

infectious

Ototoxic

disease

therapy

Neurodegenerative trauma,

Speech,

language, Coplan,

ill

when

Review

with

loss

or global

t)/.

and

/6

pathways

lie in radiation

to be associated through

with

temporal

loss loop

(mumps,

measles,

Epstein-Barr

virus)

diuretics)

field hearing

loss

bone

hearing

developmental Anon.

Joint

3

Mate/i

No.

hearing

to aminoglycosides,

fracture

child’s

with

limited

known

regarding

1987,

not

auditory

especially

concern

to be associated

but

disorder

Parental

Adaptedfrom

known

(including

drugs

Radiation

P(’(/I(lt)i(S

hearing

syndrome)

meningitis

Other

Head

or of childhood-onset

Waardenburg

delay Committee

1995

on Infant

Hearing

1990

Position

Statement.

A SHA.

1991;33(suppl

5):3-6

93

LANGUAGE Language

and

Speech

Pathologic entities giving rise to MR include single gene, chromosomal, and teratogenic disorders; sporadic syndromes of unknown etiology; perinatal events; and hypoxic, traumatic, infectious, or toxic postnatal insults.

DEVELOPMENTAL DISORDERS

LANGUAGE

DLD are a clinically heterogeneous group of disorders characterized by selective impairment of speech and/or language development, with relative sparing of other developmental domains. General intelligence usually is normal, or if delayed, not sufficiently so to account for the degree of Ianguage impairment observed. Hearing, oromotor function and social-emotional development are normal, and there is no history to suggest environmental deprivation. Unlike MR.

interacting with the child’s sex or unknown environmental factors as the probable cause of DLD.

of shorter speech segments ( ‘I wu wu wwwwant to go with you!’ ‘) or a complete inability to mitiate a word, referred to as ‘blockage.’ Stuttering is accompanied by signs of distress, such as facial grimacing or change in respiratory rate. The prevalence of stuttering peaks at 4% between 2#{189} and 4 years of age and declines to about I % among older children and adults. The etiology of stuttering is multifactorial. There is a strong genetic component, with two thirds of adult stutterers coming from families that have a positive history of stuttering. As with DLD, however, there is no clear mendelian pattern, but rather the suggestion that polygenic loading increases the risk for stuttering, which may be triggered by interaction with one or more unknown environmental factors. ‘

.

.

.

.

.

.

‘

‘

AUTISM

Autism is characterized by delayed and deviant language development, impaired affective development, monotonously repetitious behaviors with an insistence on maintenance of routines, and an onset before 30 months of age. Prevalence estimates for autism conventionally are quoted as two to four children per 10 000 (0.02% to 0.04%). This figure, however, primarily reflects young children whose autism is moderate to severe. Many of the classic diagnostic features of autism wane with time, although the affected individual remains autistic and significantly impaired. At present, however, no satisfactory criteria exist for diagnosing

DYSARTHRIA

Unrecognized hearing loss may exert long-term effects by disrupting CNS development, not just at the level of auditory perception, but at the level of language processing. there are no universally accepted standards for diagnosing DLD. Prevalence estimates vary, therefore, depending on the definitions used and the ages at which subjects have been tested. A reasonable estimate is that DLD affects 5% to 10% of preschool children. Affected boys outnumber affected girls by approximately 3:1. DLD sometimes can be traced to a specific underlying factor, such as sex chromosome aneuploidy, fragile x syndrome, neonatal intracranial hemorrhage, fetal alcohol effects, head trauma, or human immunodeficiency virus encephalopathy. Rarely, DLD is associated with epileptogenic spike-wave activity in one or both temporal lobes without any outward manifestation of seizure activity. Fluctuating hearing loss due to otitis media with effusion in the first 12 months of life has been implicated as the cause of DLD in some children. In the majority of cases, however, the etiology of DLD remains unknown. Family history for speech delay frequently is positive, usually without a clear pattern of mendelian inheritance, suggesting polygenic inheritance of a predisposition for DLD 94

autism in middle childhood, adolescence, or adulthood. Furthermore, autism can occur with any degree of severity from mild to profound; some individuals who do not satisfy all of the formal diagnostic criteria for autism clearly lie on the spectrum of autistic disorders. A more realistic prevalence estimate, taking into account children who have partial expression of the autistic syndrome, is 20 per 10 000 (0.2%). Autism can be caused by most of the same agents that give rise to MR. An association has been reported between autism and fragile X syndrome,6 but this may reflect ascertainment bias.7

Dysarthria refers to physical handicap of the muscles of speech production; symbolic aspects of language function are intact. Dysarthria in children usually is encountered as one component of generalized, static, upper motor neuron encephalopathy, cornmonly known as cerebral palsy (CP). The prevalence of CP is approximately three children per thousand, and approximately one third of affected children will manifest dysarthria. With the possible exception of very-low-birthweight infants, most cases of CP are not due to perinatal events, but stem from prenatal factors, such as intrauterine infection or congenital malformation of the central nervous system.8 M#{246}biussyndrome (facial diplegia) rarely occurs as an isolated developmental feature outside of the setting of CP.

STUTTERING

NONCAUSES

Physiologic disfluency, marked by transient loss of normal rate and rhythm of speech, is a normal phenomenon among children between 2#{189} and 4 years of age. Physiologic disfluency typically involves repetition of whole words (“I want I want... I want to go with you!”) and is unaccompanied by subjective signs of distress in the child. Stuttering, or dysfluency, involves repetition

LANGUAGE

...

Pediatrics

OF

SPEECH

OR

DELAY

Birth

order, uncomplicated twinning, ‘laziness,’ bilingualism, and tonguetie all are invoked from time to time as causes of speech or language delay; in fact, none of these actually delays speech or language development. Later-born children speak no later than first-borns. Normal twins do not speak significantly later than normal single-born children. If a par‘

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LANGUAGE Language and Speech ent or sibling is speaking for the child, this is the result, not the cause, of the child’s delay! Although toddlers may be noncompliant, they are developmentally incapable of being ‘lazy. Advice such as ‘Don’t give him what he wants until he says the word for it’ is unhelpful and only creates conflict between a speechdelayed child and his or her parents. Children reared bilingually may intermix vocabulary and syntax freely for the first 24 to 30 months of life, but developmental constants, such as vocabulary size, length of utterance, linguistic complexity, and intelligibility, are normal, and by 36 months the child essentially is a fluent bilingual speaker. ‘

‘ ‘

‘

‘

Pathogenesis Pathophysiology

and

Classical neurology consists of deducing brain function from the pattern of deficits and residual abilities after destruction of discrete regions of the brain; most of what we know about brain-language interrelationships is based on studies of adult stroke victims. Several obstacles exist to deciphering the pathophysiology of language disorders in children. Infants usually sustain diffuse rather than discrete insults (eg, intrauterine viral infection, fetal alcohol effects). Language functions are less well localized in the child’s brain compared with that of the adult; even an anatomically discrete lesion in a young child may not have as specific effects as the same lesion in an adult. Infants and very young children do not have a history of normal language development from which the clinical investigator may draw structural-functional inferences by comparing residual abilities with the subject’s premorbid state. Finally, identical lesions in infants and older children produce different effects, depending on the point in the developmental sequence when the lesion is sustained.9 The effects of hearing loss on language development are mediated via two pathways. The obvious pathway is via the effect of hearing loss on speech perception: The less well a child can hear, the more difficult it is to learn to speak. A less obvious but Pediatrics

in Review

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probably equally important pathway is via distortion of central nervous system (CNS) maturation during a critical period for language development. A critical period is an interval early in the development of a biological system during which the system is maximally sensitive to a specific outside stimulus, the effect of which may be to ‘trigger the course of further normal development or [to] produce an irrevocable result not modifiable in subsequent development.’ 10 Such a period exists for early postnatal maturation of auditory pathways in animals, and a similar phenomenon almost certainly occurs in human infants. Unrecognized hearing loss may exert long-term effects on disrupting CNS development, not just at the level of auditory perception, but at the level of language processing. For example. the mean age at diagnosis of profound congenital deafness in the United States is 24 months. Most deaf infants, therefore, are denied language stimulation of any kind during the critical first 2 years of life. Deaf infants born to deaf parents show better language development than similar infants born to hearing parents, owing in part to deaf parents providing their infants with appropriate language stimulation via ASL from the moment of birth. ‘

.

.

.

‘

Stuttering persistence increase

‘

‘

‘

‘

(dysfluency) for more than 6 months, onset or beyond age 5 years, or a positive family history the likelihood of stuttering.

DLD

is seen after focal brain dambut lesions in the Wernicke or the Broca area during infancy do not produce syndromes analogous to their adult counterparts, and such ‘pure” forms of language disability are virtually nonexistent on a developmental basis.’2 Volumetric magnetic resonance imaging (MRI) studies have demonstrated subtle abnormalities of the perisylvian cortex in some boys whose language development is I I

‘

delayed. Abnormalities have been described or theorized in the brain stem, limbic system,’3 temporal lobes, and cerebellum’4 to account for the features of autism. At present, however, there are no known neuroanatomic or neu/995

rophysiologic abnormalities that are either necessary or sufficient to give rise to autism. MR is the consequence of widespread abnormalities of cerebral architecture, neurotransmission, or myelination. In some cases the pathophysiology of MR has been elucidated, as in the essential facilitation of cerebral development by thyroid hormone or the disruption of neuronal migration caused by prenatal exposure to ethanol. Defective dystrophin-mediated regulation of cerebral development may account for the 30% prevalence of MR among boys who have Duchenne muscular dystrophy. In most cases, however, the pathophysiology of MR remains unknown. The pathogenesis of language delay in MR also is unclear. The ‘cognitive hypothesis’ holds that language is a direct expression of general cognitive development, and language delay is regarded as a symptom of MR itself. The ‘correlational hypothesis’ holds that Ianguage and cognition both represent outward manifestations of more fundamental cerebral processes, such as the ability to infer rules and hierarchical relationships from primary experience. According to this model, any insult sufficiently diffuse to im-

pair these fundamental impair both language

processes will and cognitive

ability simultaneously.’5 Both of these models predict that language delay will be proportionate to the degree of global cognitive delay, which is the case for individuals who have uncomplicated MR. The less intuitive ‘modular hypothesis’ holds that language and cognition are separate functions (“modules”), with cognition being neither sufficient nor necessary for the development of language.’6 Cognition may exist in the absence of language, as in an adult following a left temporal lobe stroke. Conversely, language may develop in relative isolation from cognition, as in the superficial “cocktail party ‘

‘

95

LANGUAGE Language

and Speech

chatter” of the child who has hydrocephalus or Williams syndromesyntax and grammar are correct, but speech is shallow and of limited content. Hyperlexia (the ability to decode printed matter by rote at a level far above the person’s other cognitive abilities), frequently seen in autism, also may represent an example of modular development of language. The pathogenesis and pathophysiology of stuttering remain obscure; an abnormality of interhemispheric

Frequency

in

communication long has been suspected)7 In adults, stroke has resuited in the sudden disappearance of lifelong stuttering or the sudden emergence of stuttering. Ablation of tissue in one hemisphere, freeing contralateral speech centers from the interference of dyssynchronous input, has been postulated to explain the former; disruption of interhemispheric pathways has been suggested to explain the latter. Dysarthria arises because of impairment to the upper

Cycles

per

Second

C) CD

C) C’)

a)

C Cl) Cl)

0 -J

C) C CD a)

I

FIGURE

1.

i.s. /)IOtt(’d

0)11 t/i(’

vertical thresholil wit/ziti

Si:nsitivitV

range

horizo,ztal

axis. Human of hearing) this

rouge,

for

/iiiinaii

C,.VIS

Izeoiring

roitiges

speech

Frequency

in decibels

from

120 i/B (the

to

I)14t c/ifjerent

hearing.

Wfl/)Iitilde

250

to) 8000

threshold .co)undS

(dB) Hz

ofpain). have

different

in cycles/sec (Hertz: is plotted i,zver.selv (liii! from 0 i/B (the

Hionan

speech

Hz) 0)0

tIle

is centered

.frequellcV/a?li/)litilde

Voiced .soiiiid.s ( ‘ ‘e, ‘ ‘ ‘ 1, ‘ ‘ ‘ ‘a, ‘ ‘ etc) ii,.e low-trequeicv, high-aitiplitude stimuli ( -5() i/B at 250 to 500 Hz). U,it’oiced sounds, or sihilants, sac/i as ‘‘f’’’’s (1,1(1 tI, ‘ ‘ are high-frequency, low-aln/)litui/e stimuli ( -20 i/B at 4000 Hz). The hearing Io).S5 of the i/u/u plotteo/ on the chart (X left ear, 0 rig/it ear) eliini,iiited perceptio)n of sibilants, thus severe/s degrading her ability to) understand speech. (Il(IFTI(li’fl.Sti(.S.

Relative

.sparuzg

created

the false

.

/,eliavior

Copyright 96

Clinical

Aspects

The hearing-impaired infant manifests auditory expressive and receptive delay; visual language is normal. Deaf infants COo and babble fairly normally until approximately 6 months of age. Thereafter, the amount of vocal output and the range of sounds in the child’s phonemic repertoire dwindle. Infants who have a hearing threshold of greater than 90 dB at and above 1000 cycles/sec have an extremely difficult time acquiring speech; auditory comprehension is equally impaired. Congenital moderate-to-severe HL (50 to 90 dB) is associated with impaired intelligibility, reduced verhal output, and reduced auditory comprehension. The hearing-impaired child may begin improvising his or her own form of sign language. The child often is labelled erroneously as having a behavior problem’ until the correct diagnosis belatedly is reached (Figure 1). The mentally retarded child manifests delay in all language areas: auditory expressive, auditory receptive, and visual. Cooing and babbling may be reduced in amount as well as delayed. Subsequent auditory expressive milestones resemble those of a normal but much younger child. Parents of a mentally retarded 3-year-old often assert that their child “understands everything we tell him.” Close questioning usually reveals that the parents are breaking everything down into a series of one-step cornmands or sequences that have been memorized as a unit. Although this may be highly functional for the child. it indicates a receptive Ianguage level of no greater than I 8 to 24 months. Delayed emergence of index finger pointing is a highly sensitive indicator of global language delay. Adaptive skills such as use of a spoon or dressing and undressing are delayed, as are play skills. Gross motor development. however, usually is normal. The child who has DLD presents with variable degrees of expressive and receptive impairment. Visual language, adaptive, play. and personal/ social development are normal. Ex‘

z

/,,,.

motor neurons or brainstem motor nuclei that govern the muscles of the face, oropharynx, and larynx.

o)t Ionc-fro’queiio#{149}v

o)f

il?i/)?e.S.SiO)1i

J)rO)i)lei?i

Anu’rioa,i

‘ ‘

iia.s

Academy

heariiig

(30-dB

threshold

at 250

Hz

in the

left

.

ear)

hearin#{231}. This child was 43 lflo)litIis o)ld befoic i/iai,’no.sei/ correct/v as Iieari,ii’ loss. Froni Cop/an J. of Pediatrics: asci/ b /n’rFnis.sioi. 1iO)rlflilI

Pediatrics

in Review

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LANGUAGE Language and Speech autistic child may be indifferent to parental entreaties one minute, but climb into the lap of the examining physician the next. The child may treat other persons as if they are objects. going through the examiner’s pockets. for example. without ever regarding the examiner face to face. Repetitous or ritualistic behaviors include rigid food preferences, fascination with bits of string or spinning objects. fixed daily routines, or repetitious unimaginative play. Autism

pressive deficits commonly include impaired intelligibility and delayed emergence of sentence structure. Speech may be ellortful and reduced in tOtLl amount. The child may begin tO invent his or her own sign Ianguage in an etlort to communicate. Receptive language may appear normal, hut difficulties with short-term auditory memory. auditory discrimination. or coiiiplex auditory comprehension tasks frequently become cvident when the child is old enough to cooperate with suitable testing. Occasionally a child will present having auditory agilosia: the absence of behavioral response to sound, even though peripheral hearing is normal. Auditory agnosia is accompanied by L severe expressive deficit. Auditory agnosia may be associated with epileptogenic teinporal lobe activity on electroencephalography ( EEG) and may he lifelong or of sudden onset in a previously normal child (“acquired epileptic aphasia.’ or LandauKlefiner syndroiiie). The autistic child manifests delayed and deviant language, impaired affecti ye development, and repetitious behaviors with an insistence on preservation of routines.19 Language is deviant or ‘atypical’ in the sense that many of the language features are not normal for a child of any age. The hallmark i)t the autistic type of language disorder is impaired pragmatics-lailure to use language as a medium of social interaction. The deficit in social interaction may be evident from infancy. with failure to make eye contact, to engage in reciprocal vocalization, or to point to desired objects. Speech consists mainly of rhetorical naming of objects and echolalia (repetition of the utterances of others). Echolalia may he immediate or delayed, typically including television commercials, segments of dialogue committed to memory from home videos, or other scripted material. Prosody (inElection) may be sing-song. robotlike, or stilted. The autistic child fails to give or receive affection in the usual manner. The child is not cuddly as an infant, does not like to be held, does not run to a parent for comfort after minor injuries. may not discriminate between parents and strangers, and has dillIculty reading body language. The

motor function and fine motor, adaptive, gross motor, play, and personal/ social development also should be investigated. Once speech or language delay has been detected, addi-

i’eo/iat,,i.s

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tional developmental testing should be undertaken by a developmental pediatrician, psychologist. speech/ language pathologist, or some combination of these individuals, depending on the extent and nature of the child’s suspected delays. Any child who fails speech/language screening or fulfills other defined criteria should undergo formal audiologic testing, regardless of how well the child seems to hear on physical

examination

(Table

2).’

Birth order, uncomplicated twinning, laziness, bilingualism, and tongue-tie are not causes of delayed speech or language. exist

may

with

any

degree of severity General intel-

from mild to profound. ligence may be normal,

although

ap-

proximately 51)C% of all children who are autistic are mentally retarded as well. Terms such as Asperger syndrome, pervasive developmental disorder. and pragmatic-type developmental language disorder often are applied to children who have mild or fragmentary expression of the autistic syndrome; the wisdom of “lumping” versus ‘splitting’ such children into separate categories is controversial. In stuttering, clinical aspects usually are limited to loss of fluency with associated signs of subjective distress; symbolic aspects of Ianguage development are intact. Duration of disiluency for more than 6 months, onset or persistence of disfluency beyond 5 years of age, or a family history of stuttering all in‘

crease

the

‘

likelihood

that

disfluency

actually may herald stuttering. Likewise, in dysarthria, the defect is limited to speech production; receptive and visual language are intact. Difficulties

with

sucking

or

swallowing,

choking. or coughing during feeding may be the initial clues to significant oromotor impairment. The

best

test

for

detecting

speech

or language problems is a comprehensive history. encompassing auditory expressive, auditory receptive. and

visual

language

(Figure

2).

Oro-

Most hearing-impaired children have sufficient residual hearing to make gross responses to sound, even though perception is severely cornpromised; even profoundly deaf children commonly are missed by the examining physician because they ‘cheat’ by avidly using visual cues. The two most common causes of deafness are isolated recessive deafness and intrauterine CMV infection. The recurrence risk fbr the former is 25c% the recurrence risk for the latter is close to zero because the mother’s seroimmune status protects subsequent fetuses. Virologic and serologic ‘

‘

;

studies

for

CMV

should

be

obtained

routinely on newborn infants who have i ntrauteri ne growth retardation or microcephaly

of

unknown

cause;

these studies are of no diagnostic value beyond the first month of life. Ophthalmologic evaluation and a computed tomographic (CT) scan of the brain. searching for choreoretinitis and intracranial calcifications, respectively, occasionally support a presumptive diagnosis of intrauterine viral infection. In the absence of a proven etiology for the child’s hearing loss, evaluation by a medial geneticist is indicated. The parents and siblings of an infant who has hearing loss of unknown etiology also should be tested fIr hearing loss. G-banded karyotype and cytogenetic or DNA probe studies for fragile X are indicated in children who have mental retardation:#{176} autism, or developmental language disorder. Human

(HIV)

immunodeficiency

serology

should

virus

be considered 97

LANGUAGE Language and Speech

ELM

EARLY

SCALE-2

MONTHS

1

LANGUAGE

MILESTONE

SALE-2

22

24

26

28 Examin

32

34

36

2 1

Coo

Reciprocal

2

37

1

vocalization

[15A one-half 19 Three-fourths

by strangers

20A11/Almost

_________________

47

All

I

3Laugh LU f

o

r5 Mono. 8polysyllabic 7

#{149}

babbling L babbling

word

1

Alerts

to

2

P

6lnhibits TI

7Bell, 1-Step

B

laterally

to

Recognizes

Points

Driflk with

to objects S,on

Wt.wth Eat,/th

)

‘I

by use

‘I

commands

13

2/4)

Th’o

body

parts wlo gestureL’

I

On top Behind -Basde

-f-,-’.-’--4-----I---------

I

2/4)

I

AE

objects

tVisual

I

AR

V

Global Lang.

Intell.

Pass/Fail

to facial

tracking

expressions

Raw

(H,V)

Score

+

(NA)

+

Percentile

#{176}

-

(NA)

6Blinkstothreat

TI

Imit. Step

gest.

comm. 9lnitiates

2

3

Std. S. Equiv.

games

4

Points 5

to desired 6

(NA)

._____‘

Age Equiv.

w. gest. I gest. games 10

7

8

Only

i

objects 9

10

11

12

14

16 AdOlbenal

OI093.T5e3bJ.m.sColan.MD

FIGURE expressive,

I

parents

‘I

1

12

-]

Responds

MONTHS

5Bell,over&down bell

9Pointsto 1 105tp commands

3Recognizes

>

_

Smiles 2

Cl)

_

1

I

-a 4

_

I

Ban

gesture

ball

I 1

Cp

described

w/o

Me spoon) Mom Meb.)l/Momspoon1 Mom b&)/M.cop

/1.5!

‘I

objects

‘L

command 2/3)

to named

(213)

laterallyto

Use

5jfl

1I Points

to voice

I4Orients

and

2/4) Cup Ba)) Spoon C,ayon

L

Conversations

17

sounds

“No”

diagonal

Prepositions

words 11

Recognizes

Name

__________

(Not”Mama/Dada”)

Orients 3

AnyI 16

4-6 Single

Objects:

I

wds

l4aMe/youe:

voice

I I

Single

Correct

10

.

18

_____________

sentences

1350+

I___________

“Mama/Dada”: Any “Mama/Dada”: 9First

I

I

I

‘1Tells2wants ‘22Wd

18 oogwotthd

20

if age

22 foTm)aBBa2lTn.y

(NA)

or developmental

24

26

be ootmed

level

28 from

PRO-ED.

is 12 months

30

32

8100

Shod

or (ass

34

Cmok

Clod..

36

huCin.

TX 18758

2.

The Ear/v Language Milestone Scale, second edition (ELM Scale-2), functions as a structured history of auditors’ auditory receptive. atid visual language development from birth to 36 months of age and of intelligibility of speech froni /8 to 48 months of age. Tile ELM Scale-2 can be used as a screening tool or as a semniquantitati%’e measure of language development. ELM Scale-2 score sheet from Coplan J. The Early Language Milestone Scale. Ed 2 (ELM Scale-2). PRO-ED, 8700 Shoal Creek Blvd. Austin, Tex. © 1983, 1993, used by permission.

in speech-delayed preschool children because speech delay may be an early indicator of HIV encephalopathy. ‘ Boys who have speech delay plus gross motor delay but who do not

have

clearly

increased

deep

ten-

don reflexes should undergo creatine kinase determination to rule out Duchenne muscular dystrophy. Electroencephalography should be undertaken in the rare child who has auditory agnosia; otherwise, the study is of little benefit in the evaluation of speecManguage delay. Imaging studies such as cranial CT or MRI seldom are informative, except in the presence of focal neurologic abnormalities or dysmorphic features suggestive of structural brain abnormality (eg, hypertelorism, midfacial hypoplasia, aberrant hair patterning). 98

Management Management

education may be all oral or ‘total communication’ (sign language plus speech). The ability of a congenitally hearing-impaired child to read lips usually is grossly overestimated by wishful adults. Normal-hearing parents may be averse to the introduction of a hearing aid or sign language because these become visible markers of the child’s disability. The physician needs to be aware of the century-old controversy between “oral” and ‘manual’ approaches23 and ensure that decisions regarding education are dictated by the child’s needs. The physician should encourage the parents to vent their feelings, while emphasizing that the primary goal of therapy is to foster effective commu‘

for

all

children

‘

who

have delayed speech or language includes making the correct developmental diagnosis; arriving at an underlying medical diagnosis; rendering appropriate genetic counseling (eg, recurrence risk); assuring that the child receives appropriate habilitative services; and assuring that the child, his or her parents, and his or her siblings receive appropriate supportive care so that family functioning is not compromised unduly. A trial of amplification usually is indicated for the child who has permanent hearing loss and will require the expertise of an audiologist. Cochlear implantation offers exciting possibilities for many children.22 Special Pediatrics

‘

‘

nication. iii

Res’ieiv

Speech,

to the extent Vol.

/6

No.

3

that Marc/i

it /995

LANGUAGE

Language is possible, will be an outgrowth of such an approach. Language delay in the mentally retarded child must be viewed within the overall context of the MR. Enrollment in a special education program, rather than isolated speech therapy. is indicated. The transition from

home-based

i nfant

to a classroom-based

takes The

place

program

around

physician

stimulation

36 months

needs

to be

group

often

are

the

child

who

has

DLD

is to

communicate effectively. For many children, manual sign language or an augmentative communication device such as a picture board or computer that has the capability of synthesizing speech offers effective short-term palliation of the expressive deficit.24 Parents often express the fear that if they let their child ‘depend’ on signing, the child never will learn to speak. This fear is understandable, ‘

but

‘

ungrounded.

Therapy for autism should be directed at enhancing communication and social skills. Therapy for autistic children is embroiled in controversy over facilitated communication (FC), a technique whereby an assistant supports the autistic person’s hand as the autistic person types at a conventional keyboard or computer. In theory. the assistant provides only support or actually pulls the autistic person’s hand back from the keyboard after a keystroke; the autistic person is said to generate all of the output. Such output often differs greatly from the autistic person’s verbal language. adaptive skills, or level of general intelligence as ascertained by standardized measures. FC is supported primarily by emotionally cornpellin anecdotes but scant controlled data: Facilitator influence has been implicated in studies in which the autistic person and facilitator respond to discrepant stimuli (eg, delivered via headphones). The “facilitated” output often represents the correct Peo/iatric.s

in Review

Vi)!.

/6

No.

3

‘In

At

helpful.

Marc/i

received than

the

by

stimu-

‘

‘

to

stimulus rather

lus received by the autistic person.2628 A standardized test protocol is needed to separate those instances in which FC may be genuine from those in which facilitator control may be operating. ‘Does FC work?’ is probably not a fruitful question. Rather,

alert

to the

facilitator,

usually

The child who has DLD should be referred for speech/language therapy. As with the child who has a severe hearing loss, the first therapeutic goal for

the

of age.

signs of family decompensation (physical abuse, parental separation, unresolved grieving or anger, dysfunctional behavior in siblings). Family therapy or participation in a support

response

the

‘

questions

whom

does

present,

appear

FC

work

however,

to be and

how?”

physicians

car-

ing for autistic persons face a terrible dilemma. Rejection of FC (because it lacks a plausible neuropsychological explanation or objecti ye empirical support) may condemn the autistic child to an unnecessarily isolated existence. Conversely, uncritical acceptance of FC may raise parents’ hopes falsely, inspire parental feelings of inadequacy if they cannot achieve the same results as those touted by their child’s facilitator at school, or cause harm

in medicolegal

standardized

settings.28

protocol

A

to assess

the

Most

preschool

experience

complete

I or 2 years

mastering

mitted

as evidence

in a court

be adof

law.

Stuttering requires referral to a speech/language pathologist. Admonitions by the physician or parent that the child should simply ‘slow ‘

down’

‘

are

of no

value

and

are

po-

tentially harmful. Anecdotal reports, primarily from the adult literature, have suggested benefit from an array of drugs,

including

benzodiazepines,

calcium channel blockers, parasympathomimetics, and haloperidol.29 At present, however, most therapy in children is behavioral.

Prognosis Prognosis for the child who has HL varies, depending on the age at onset of

HL,

age

at introduction

of amplifi-

cation and speech/language therapy, degree of HL, and presence of other disabilities. The prognosis for speech and language development in the mentally retarded child is governed by the degree of MR. Even with optimal care, the gap between the mentally retarded child and his or her age mates will widen steadily with the passage of time. /995

resolution

of

by

equal

difficulty

in

written

language.3#{176} The author has coined the term ‘the prelearning disabled child’ to describe the situation in which the child’s speech is no longer a developmental concern, but the child has not yet fallen far enough behind academically to meet regulatory guidelines ‘

‘

for academic intervention rate with a diagnosis of

commensulearning dis-

ability. Prognosis for the autistic child varies with the severity of the autism and the degree of any accompanying MR. Severely autistic children or those who have MR and autism gen-

cant qualitative ha and delayed

not

have

their developmental disorder. For many others, however, difficulty with acquisition of spoken language is replaced after a honeymoon period of

produced

should

who

develop

erally

FC25

children

reasonably clear speech by entry to kindergarten or first grade. Some children who have DLD DLD

validity of FC case by case will be of inestimable value in sorting through these issues. Until such a protocol is available, allegations of sexual abuse by

and Speech

continue

to demonstrate

dis-

abling autistic tendencies for life. Nonretarded children who are mildly to moderately

are replaced a tendency

autistic

show

by verbal literalism to dwell at length on

scure conversational tact and social skills though

the

signifi-

improvement. Echolaecholalia gradually

child

and ob-

topics. Eye conimprove, al-

still

has

great

difficulty reading social cues. Diagnosticians encountering a high-functioning autistic adolescent for the first time may find it impossible to reason backward from the child’s improved state to arrive at the correct developmental the

diagnosis.

autistic

Often,

features

the

become,

milder the

more

difficult it becomes to obtain appropriate educational services, and the greater the risk that the child will be diagnosed incorrectly as having oppositional behavior disorder or an emotional disturbance. Seventy-five

percent

of preschool

children who stutter experience complete or partial remission of symptoms during elementary school. The chance for remission is reduced greatly if a parent or sibling also stutters. The prognosis who have dysarthria the

Some never

severity

children acquire

of the

for children is governed by motor

disability.

who have dysarthria functional speech and 99

LANGUAGE and Speech

Language remain output

dependent device

on a mechanical of some

may range from a simple board to a microcomputer speech capabilities.

kind,

which

picture that has

REFERENCES I . Petitto

Marentette PF. Babbling in the evidence for the onR)geny of language. Science. I 991:251:1493-1496 Coplan J. Gleason JR. Unclear speech: recognition and significance of unintelligible speech in preschool children. Pediatrics. l9tg:K2 (p1 2):447-452 Ruben Ri. The ontogeny of human hearing. Acta Otolarviigol. 1992: 1 I 2:192-196 Finitzo T, Gunnarson AD. Clark JL. Auditory deprivation and early conductive loss froni otitis niedia. Topics in Laiigzage 1)i.vorders. I 990: 1 1:29-42 Ornitz EM. Naruse H. Introduction to biological research on infantile autism. In: Naruse H, Omits EM, eds. Neurobiology of Imijantile Autisni. New York. NY: Excerpta Medica; 1992:3-39 Hagerman Ri. Silverman AC: Froigile X .Sy,ulronie: f)iagiio.sis. Treat,neiit. aiid Researc/i. Baltimore. Md: Johns Hopkins University Press: 1991 Fisch GS. Is autism associated with the fragile X syndronie! Am J Med Gemiet. 1992:43:47-55 Nelson KB. Relationship of intrapartum and delivery room events to long-term neurologic outcome. (‘liii Perinatol. I 989: I6:995-I (X)7 Feldman HM, Holland AL, Kemp SS. Janosky JE. Language development after unilateral brain injury. !3raimi Lang. 992: 42:89-102 Colombo J. The critical period concept: research, methodology. and theoretical issues. Psycho! Bull. 1982:91:260-275 ThaI Di. Marchman V. Stiles J. et al. Early lexical development in children with focal brain injury. Brain Lang. I 99 1:40: 49 1-527 Tuchman RF. Rapin I. Shinnar S. Autistic and dysphasic children. I: Clinical characteristics. l’edatrics. I 99 1 :88: 12 1 1-1 2 I 8 DeLong GR. Autism, amnesia. hippocampus, and learning. Neurosci Biobeliav Rt/: I 992:16:63-70 Holroyd 5, Reiss AL. Bryan RN. Autistic features in Joubert syndrome: a genetic disorder with agenesis of the cerehellar vermis. Bio/ Psyc/iiatrv. I 99 1:29:287-294 Bates E. Language development. Curr Opimi Neurobio/. I992:2: I80-I 85 Yamada JE. Laura: A Case For The Modu/aritv Of i_.oiiigiici,’e. I 990: Cambridge. Mass: MIT Press Aram DM. Meyers SC. Ekelman BL. Fluency of conversational speech in children with unilateral brain lesions. Bmain IA1!lg. I 990:38: 1 05- I 2 I Coplan J. Deafness: ever heard of it? Delayed recognition of permanent hearing loss. Pediatrics. 1987:79:206-213 Rapin I. Autistic children: diagnosis and clinical features. Pediatrics. 199 I :87( part 2):751-760 (entire supplement devoted to a review of autism) manual

2.

3. 4.

5.

6.

7.

).

9.

10.

II.

12.

13.

14.

15. 16.

17.

18.

19.

/00

20.

21.

22.

LA.

mode:

23.

24.

25.

Schaefer GB. Bodensteiner JB. Evaluation of the child with idiopathic mental retardation. Pediatr Cliii North Am. I 992: 39:929-943 Condini A, Axia G. Cattteland C. et al. Development of language in I 8 -30 month old HIV-l-infected but not ill children. All)S. 991:5:735-739 Osherger Mi. Chute PM. Pope ML, ct al. Pediatric cochlear implant candidacy issues. Am J Otol. I 99 1 : I 2(suppl):80-88 Winefield R. Never the Tivaimi S/ia/I Meet: Bell. Gal/audet, oi,i(/ tbu Communications Debate. 1987: Washington. DC: Gallaudet University Press Goldstein U. Hockenberger EH. Significant progress in child language intervention: an I I year retrospective. Res I)ev Di.sahi/. 1991:12:401-424 Prior M. Cummins R. Questions about

facil itated conliiiunicatioii J Autism?, I)ev I)isord. 26.

,nd autisni. 1992:22:331-338

Hudson A. Melita B. Ariiold report: a case study asscssing of faci litated conlnlunicatioil

.

N. Brief thc validity I Autis,,i

l)ev 1)isord. I 993:23: 165- I 73 27. Wheeler DL. Jacobsen JW. Paglieri RA. Schwartz AA. An cxpcri nscntal asscssmcnt of faci Iit1.itcd coniiiiunication. Memit Retard. 1993:31:49-60 28. Hostler SL. Allaire JH. Chrisloph RA. Childhood sexual abusc reported by facilitated coiaillunication. Pediatrics. 1993:91:1190-1192 29. Brady JP. The pharm1.icology of’ stuttering: a critical review. Ani J Psychiatry. 199 I 148:1309-1316 30. Scarborough HS. Vcry early language deficits in dyslcxic children. (/ii/d I)ev. 1990:61:1728-1743

PIR QUIZ 5.

A mother

expresses

22-month-old gether words.

concern

boy She

is not reports

that

her

putting tothat he

can produce about I 0 words a rich but incomprehensible

and has jargon;

he gets what he wants by pointing and vocalizing. Uls history records hyperbilirubinemia in the neonatal 3tfl()d, following normal pregnancy

and

delivery (birthweight. 3.1 kg). were two episodes of otitis in the first year that seemed

There media

to respond

readily

to antibiotic

apy. Developmental stones have been its. The

patient

the family,

one

(male/female). with his twin, cabulary together household Farsi). nation

ther-

motor milewithin normal is the

second

lim-

child

in

of fraternal twins He shares his jargon who has a larger vo-

and is beginning to put two or three words. The is bilingual (English! Findings on physical examiare normal. Which of the fbI-

lowing is most likely the mothers concern? A. A normal variant

to account

for

in language

development. B.

Effect

C.

Effect of living household. Partial deafness

D.

of having

a twin. in a bilingual after

hyperbiliru-

after

otitis

binemia.

E. Partial

deafness

media. 6.

8.

In the previous case. following would you

to which give the

est priority7 A. Audiometry. B. Cytomegalovirus

titers.

C.

Examination pathologist.

D.

Magnetic

E. Reexamination

7. A 22-month-old boy is referred to you because his mother is concerned that his speech development seems to be delayed. He had several words by the age of 14 to 16 months, but has not added any new ones. She also is concerned that he has become difficult to manage, preferring to spend a lot of time alone, intent Oil repetitious manipulations of small objects and resentful of inlrusions. His lather feels that there is no problem ( ‘ ‘My mother says I was a strong-willed child. to’ ) the parents are having considerable strife over this difference of opinion. The boy was born at 38 weeks’ gestation (hirthweight 2.8 kg). had hyperbiliruhinemia in the first week, and had three episodes of otitis media in the first year without apparent complicatiofls. You find no abnormality on physical examination, which is dullcult to perform because you cannot get the patient’s attention. much less his cooperation. Your tentative diagnosis is: A. Auditory agnosia. B. Autism. C. Conduct disturbance due to faniily discord. D. Conduct disturbance in a partially deaf child. E. Degenerative disease of the central nervous system. In the previous case. all of the fbIlowing are true except: A. Chromosomal analysis often is indicated. B. Many children who have this condition are mentally retarded. C. Special education is indicated. D. The pathophysiology of this condition is unknown. E. This condition often is the result of emotional trauma.

of the high-

by a speech resonance imaging. in 2 to 3 months.

/‘(I(/i(,t,.i(.c

ill

Rel’IeIl

‘o/.

/6

No.

3

Maic/i

/995

Normal Speech and Language Development: An Overview James Coplan Pediatr. Rev. 1995;16;91-100 DOI: 10.1542/pir.16-3-91

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