Speech and Language Development and Disorders

CHAPTER 16


Speech and Language Development and Disorders


Michelle M. Macias, MD, FAAP Angela C. LaRosa, MD, MSCR, FAAP Shruti Mittal, MD, FAAP


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Language acquisition is one of the most important components of a child’s development. Language represents objects or actions in symbolic form and communicates ideas, intentions, and emotions. Effective communication is necessary for social-emotional development and interactions, learning, and effective functioning in society. Speech and language disorders are one of the most common developmentally disabling disorders of childhood, and 30% of parents voice concerns about language development during primary care visits.1 Functions of the pediatric primary care medical home include promoting language development, alleviating concerns about language development, and/or detecting language development problems. Early recognition of language delays and intervention are necessary to provide children with speech and/or language disorders with the best possible outcome.


Communication skill development begins at birth. Infants communicate nonverbally through facial expressions and gestures and verbally through sounds and primitive words, and they soon learn that speech is a more efficient means of communication. Language development occurs in an orderly and predictable manner for most children; however, variations can occur. Virtually any disruption in brain function can affect language acquisition; therefore, a variety of conditions affecting the brain are associated with language problems. Delays in comprehension and/or expression not associated with other developmental or neurological problems are found in 5% to 16% of children aged 2 to 5 years, with a significantly higher proportion of boys being affected.2


Primary pediatric health care professionals should be careful not to attribute cultural or gender differences as reasons for delayed language development. Children who learn 2 languages simultaneously follow the same pattern of speech and language development as monolingual language learners. The child may have a period when he or she mixes the 2 languages, but this should gradually disappear as language skills develop.3 Studies have shown that girls are more talkative (have more total words) than boys at all ages, with significant gender differences found between 1 to 2.5 years of age.4 Although some boys may develop expressive language more slowly than girls, it is generally only by a few months and still within the accepted time frame. Language development is almost never delayed because the child “doesn’t need to speak” (eg, “her big sister always talks for her”). There is a tremendous motivation to improve communication, as the use of verbal labels allows the child to meet needs more efficiently than pointing.


The term language delay implies the delay will resolve, and the child will catch up at some point. This varies depending on the type of language delay. Natural history studies reveal a 40% persistence rate for children with expressive language delay alone but a 70% persistence rate for those with mixed receptive-expressive language delays.2,5 More than 40% of children with early delayed language that normalizes demonstrate later reading or cognitive difficulties.6 Preschoolers with language disorders are at higher risk for language-based learning disorders and social and behavioral problems.7,8 Speech and/or language concerns should not be dismissed with reassurance that the child will “catch up,” given the possibility of future difficulties and better outcomes with earlier detection of these problems.


Dimensions of Speech and Language


Speech produces complex acoustic signals that communicate meaning and is the result of interactions between the respiratory, laryngeal, and oral structures. This acoustic signal varies with regard to vocal pitch, intonation, and voice quality. The signals need to conform to the language code so that they can be decoded as meaningful communication.


Language involves both expressive and receptive components. Expressive language involves the communication of ideas, intentions, and emotions. Receptive language involves understanding what is said by someone else. Receptive language includes auditory comprehension (listening), literate decoding (reading), and mastery of visual signing.


Language has several components, as outlined in Table 16.1. The simplest “units” of language are phonemes, or individual sounds. Phonemes are combined to produce morphemes, which are the meaningful units of sound combined to produce a word.














































Table 16.1. Components of Speech and Language


Term


Definition


Speech


Intelligibility


Ability of speech to be understood by others


Fluency


Flow of speech


Voice and resonance


Sound of speech, incorporating passage of air through larynx, mouth, and nose


Language


Receptive language


Ability to understand language


Expressive language


Ability to produce language


Phoneme


Smallest units of sound that change the meaning of a word (eg, “map” and “mop”)


Morpheme


Smallest unit of meaning in language (eg, adding “s” to the end of a word to make it plural)


Syntax


Set of rules for combining morphemes and words into sentences (grammar)


Semantics


The meaning of words and sentences


Pragmatics


The social use of language, including conversational skills, discourse, volume of speech, and body language



The lexicon (vocabulary) is the collection of all of the meaningful words in a language. Syntax (grammar) is the order of words in phrases and sentences. Semantics are the individual word and sentence meanings. The literal interpretation of words can be modified by prosody or vocal intonation. The social use of language is known as pragmatics.


Typical Speech and Language Development


The concept of “critical periods” is generally accepted for speech/language development in infancy and early childhood.9 Table 16.2 shows the typical ages for attaining language milestones, although variability exists. Some skills may be demonstrated by the child during the office visit, while others may rely on parent report.


























































Table 16.2. Speech and Language Milestones


Age


Receptive Language


Expressive Language


0-3 months


Alerts to voice


Cries, social smile Coos


4-6 months


Turns to voice, na me


Laughs out loud Blows raspberries, clicks tongue Uses single consonant sounds, then begins babbling


7-9 months


Turns head toward sound


Says “Mama” and “Dada” indiscriminately


10-12 months


Enjoys “peek a boo”


Understands the word “no”


Follows 1-step command with gesture


Says “Mama” and “Dada” specifically Waves “bye-bye”


Begins to gesture Shakes head “no”


First word other than “Mama” or “Dada”


13-15 months


Follows 1-step command without gesture


Points to 1 body part


Points to ask for something or to get help


Nonspecific jargoning


Uses 3 words (other than names)


16-18 months


Points to 1 picture Points to 2 body parts


Points to object of interest to draw attention to it


Mature jargoning with true words Up to 10 words (other than names)


Uses giant words: “all gone,” “thank-you”


19-24 months


Begins to understand pronouns Follows 2-step commands Points to 5-10 pictures


Up to 50 words


Two-word phrases, then sentences


25-30 months


Understands “just one” Points to parts of pictures


Uses pronouns correctly


Speech is 50% intelligible to strangers


3 years


Knows opposites


Understand simple prepositions (eg, on, under)


250+ words 3-word sentences


Answers “what” and “where” questions Speech is 75% intelligible to strangers


4 years


Follows 3-step commands Points to 4 colors


Uses 4-word sentences Answers “when” questions Knows full name, gender, age Tells stories


Speech is 100% intelligible


5 years


Begins to understand left and right Understands adjectives


Answers “why” questions Defines simple words


Pre-Speech Period


Children’s communication development begins shortly after birth through social interactions with adults, which are necessary for bonding and having the infant’s needs met. Infants are able to distinguish their mother’s voice and show preference for familiar adults from early on in the first few months of life.10 By a few months of age, the infant realizes that some sounds are important and specifically reacts to them. By 6 months of age, an infant recognizes the basic sounds of her native language and has clear self-driven imitation of other’s speech, with a rich interplay between the infant and the older individuals in her life.


Vocal development begins with phonation in the first few months (guttural or throaty sounds), then progresses to primitive articulation or cooing between 2 to 4 months of age. This expands to full vowel sounds by 4 to 5 months of age, single consonant sounds by about 5 months (eg, “ah-guh”), and well-formed babbling (repeated consonant-vowel pattern, eg, “bababa”) at around 6 months of age. Receptive language skills and social routines also develop in the first year of life. Six-month-old children may pause momentarily when they hear their name called, and by 10 months pause at the word “no.” At approximately 10 months of age children begin to gesture, holding their arms up to be picked up, waving bye-bye, and engaging in social games such as peek-a-boo.


Naming Period


Around their first birthday, children respond appropriately to requests for identification of familiar people or objects. Pointing is also used in a variety of contexts and is an important expression of nonverbal communication. A child uses protoimperative pointing to a desired object in order to get an adult to obtain the object for him; the child “imperiously” implies, “I need that!” by pointing to the object. Protodeclarative pointing is used when a child attempts to get an adult’s attention to look at something of interest to the child and is a key component of joint attention. A child may also point to an object and vocalize in a questioning tone in an attempt to have an adult name that object for him.


Formal vocabulary development usually begins with the first word by an infant’s first birthday and may include immature words such as “ba” for bottle or “cu” for cup. Vocabulary steadily expands, and by 2 years, a child may add 1 new word a day to include approximately 200 words by 2.5 years of age and more than 10,000 words by the time a child enters first grade. A child’s receptive vocabulary is much larger than the number of words he or she uses expressively.


At 13 to 15 months of age, a child begins to jargon, or mimic mature conversation, by varying intonation and pitch but initially does not use true words with this immature speech. Parents may report their child sounds like he is “talking in a foreign language.” As new words are learned, they are incorporated into the child’s speech patterns (mature jargoning). First words are usually nouns used to label objects. Between 12 and 18 months of age, a child uses single words to communicate desires (eg, “more”), emotions (eg, “no”), and specific objects (eg, “baby”).11


Word Combination Period


At around 18 months of age, when a child has a 20-word vocabulary, she begins to combine words into phrases. Initially, word combinations tend to be “giant words” (ie, words the child often hears used together, such as “thank you” and “let’s go”). Next, the child combines words into novel phrases (eg, “big truck”), and then into 2-word sentences (noun + verb, verb + object [eg, “want ___”]).11


Sentences


A rough rule of thumb is that 90% of children use 2-word sentences at 2 years of age, 3-word sentences by 3 years of age, and 4-word sentences by 4 years of age.12 Sentences become increasingly complex as the child’s understanding of grammar and language develop. By 3 to 4 years of age, children are able to understand and use prepositions (eg, “under” and “on”), adjectives, and adverbs. They begin to ask and answer questions. Semantics (word and sentence meaning) and syntax (grammar) improve over time, and by 5 years of age, children have complete mastery of grammatical tense marking. The child’s pragmatic language skills also develop as the child learns the rules of social communication.


Promotion of Language Development


As with all areas of development and behavior, promotion of language development is a function of the primary care medical home and is a component of the strength-based approach to primary pediatric care. Optimal language development occurs when children experience stimulating environments with predictable and developmentally appropriate responses from adults. Some families may need guidance in strategies to encourage language development. Parents should be encouraged to “make their house a language house,” essentially, talking throughout daily activities with their children, no matter how mundane the activity. Reading aloud to young children has known positive effects on language and later reading decoding skills, as evidenced by research on Reach Out and Read, a primary care–based literacy promotion program. Studies have shown that parents use more complex language and more book-to-life comparisons when they read to young children using picture books rather than when they read books with text.13 This helps to promote oral language usage and conversational speech. The American Speech-Language-Hearing Association (ASHA) has handouts on language stimulation activities for young children that can be downloaded, reviewed, and provided to families (www.asha.org/public/speech/development/Parent-Stim-Activities.htm). Parents should be reminded that television is not a substitute for language and should be avoided in the first years of life. Babies and young children do not get the same language stimulation from television as they do from personal, verbal interactions.


Variations in Development


Children’s speech and language development is generally an orderly process, but like most aspects of development, language emergence is characterized by variation. When a parent raises a concern about language, the child will ultimately fall somewhere on the continuum of language developmental variation, language problem, or language disorder. Administering a standardized general developmental screen or language-specific screen will help the clinician determine where the child lies on this continuum. If the child passes the screen or has a borderline score, then watchful waiting is an appropriate next step to the discussion of language stimulation activities, with close follow-up and repeat screening in the medical home. If the child fails the screen, then referral to early intervention or early childhood programs (Head Start, preschool) and referral to a speech and language pathologist is recommended.


A speech-language or communication disorder is defined as an impairment in the ability to receive, send, process, and/or comprehend verbal, nonverbal, or graphic symbol systems.14 The most common variation in language development is language delay. The word delay inherently implies that catch-up will occur. Of children with early language delays, approximately 60% will catch up by 4 years of age with no persistent problems.5 Another variation is language dissociation. This can occur either within the language domain, as seen when developmental rates differ between expressive and receptive language, or between different domains (eg, language and motor skills). Deviation in language development occurs when language development deviates from the norm, for example when children learn more advanced language-based concepts before they have mastered early language milestones. An example of this is a child who is able to recite the alphabet or TV jingles but is not yet able to communicate needs using words and phrases. Deviated language development can often be a sign of autism spectrum disorder (ASD).15


Young children with late language emergence, or “late talkers,” can be especially perplexing to primary pediatric health care professionals. Which children are just slower to develop expressive language but will catch up, and which children will continue to experience language delay? Generally, late talkers are those children aged 18–23 months of age with expressive vocabularies fewer than 10 words and/or those children 24–34 months of age whose expressive vocabulary consists of 50 words or less and/or are not using 2-word combinations.16 Factors associated with decreased risk of continued language problems include age-appropriate receptive language, a greater number of gestures used to compensate, a younger age at diagnosis, and continued progress with language development.


Some late talkers resolve or appear to resolve their expressive language delays. However, resolved late talkers (RLT), from childhood through adolescence, often score lower on language tests than children with typical language development. Language-related problems can emerge in the later school years when more advanced language-related skills are needed.16


Speech Disorders


Speech disorders reflect problems with creating the appropriate sounds representing the language symbols (the words). These problems include phonological (articulation) disorders, dysarthria, apraxia of speech, voice disorders, and speech fluency disorders. Speech disorders may or may not also include impairments in expressive language.14


Phonological or Articulation Disorder


A phonological or articulation disorder is characterized by the substitution, omission, addition, or distortion of phonemes and represents most speech therapy referrals. Children master sounds at different ages depending on the difficulty in producing the sound. In the first 2 years, children master simple sounds, including all vowels and the consonants /b/, /c/, /d/, /p/, and /m/. More difficult sounds, such as the consonants /j/, /r/, /l/, and /v/ and blends (ie, sh, ch, th, st), may not be mastered until 5 or 6 years of age.


Dysarthria


Dysarthrias are motor speech disorders that involve problems of articulation, respiration, phonation, or prosody as a result of paralysis, muscle weakness, or poor coordination.17 Dysarthric speech is characterized by weakness in specific speech sound production and is frequently associated with cerebral palsy. Dysarthric speech may also encompass problems in coordinated breath control and head posture.


Apraxia of Speech or Dyspraxia


Apraxia of speech, or dyspraxia, is a speech disorder that arises from difficulties in complex motor planning and movement and involves problems in articulation, phonation, respiration, and resonance. This results in a child having difficulty correctly saying what he or she wants to say. The child has problems putting syllables together to form words and has more difficulty with longer words rather than shorter, simpler words. It is not due to weakness of the oromotor musculature as seen with dysarthria. Therefore, apraxia/dyspraxia can usually be differentiated from dysarthria by the lack of association with other oral-motor skills, such as chewing, swallowing, or spitting. Other neurological “soft signs,” such as generalized hypotonia, may be present on examination and can result in fine motor or gross motor difficulties.18 Apraxia can be categorized as acquired or developmental. Acquired apraxia/dyspraxia commonly results from head injury, tumor, stroke, or other problems affecting the parts of the brain involved with speaking and involves loss of previously acquired speech. It may co-occur with dysarthria or aphasia, a communication disorder impacting understanding or use of words caused by damage to the language centers of the brain. Developmental apraxia of speech, also referred to as childhood apraxia of speech (CAS), is present from birth. A hallmark feature of CAS that distinguishes CAS from phonological disorders (where speech errors are consistent) is the inconsistent error pattern on consonants and vowels in repeated productions of syllables or words observed in CAS. For example, a child with CAS might be able to say the /t/ in the word “top.” However, when he or she says the /t/ in the word “water” the /t/ might sound like an /n/ or a /d/, resulting in “waner” or “wader.” Individuals with apraxia or aphasia might have difficulty with verbal expression; however, apraxia on its own does not present a problem with language comprehension. Apraxia of speech is differentiated from an expressive language delay in that children with expressive language delay typically follow a normal language trajectory but at a slower pace. It can be difficult to differentiate between expressive language delay and apraxia before the age of 2 years. Development of receptive language is often unaffected in apraxia. Because individuals with apraxia of speech demonstrate similar language concerns as individuals with expressive language disorders and dysarthria, it is necessary for examiners to administer an oral-motor examination to help differentiate the 2 conditions. Some helpful aspects of the oral-motor exam might include pursing of the lips, blowing, using a straw, licking the lips, and elevating the tongue. Children with apraxia will generally have difficulty imitating oral-motor movements but will not demonstrate weakness. Children with dysarthria will exhibit decreased strength and coordination of speech musculature, and speech errors are usually distortions. Standardized tests for praxis can be completed by speech-language pathologists. In regard to treatment options, 2 motor treatments (Dynamic Temporal and Tactile Cueing for Speech Motor Learning [DTTC] and Rapid Syllable Transition [ReST]), and one linguistic treatment (Integrated Phonological Awareness Intervention) have the most evidence supporting their use.19


Voice Disorders


Variations in pitch, volume, resonance, and voice quality can be seen in isolation or in combination with a language delay. Impaired modulation of pitch and volume can be seen in children with ASD, nonverbal learning disorders, and some genetic syndromes. Hyper- or hyponasal voice quality suggests anatomical differences or sometimes neurological dysfunction, with hypernasal speech occurring secondary to velopharyngeal palatal incompetence and hyponasal speech arising from air impeded by large adenoids.20 Velopharyngeal palatine incompetence (insufficiency) can be a marker of 22q11.2 microdeletion syndrome.


Fluency Disorders


A fluency disorder involves the interruption in the flow of speaking. Examples of dysfluent speech include pauses, hesitations, interjections, prolongations, and interruptions. This is common in early childhood (age 2.5 to 4 years), and at that time is categorized as normal dysfluency of childhood. Persistent or progressive dysfluency is more likely stuttering, which arises in the preschool years for most affected children. Red flags indicative of pathological dysfluency requiring speech therapy include repetitions associated with sound prolongations (eg, “ca-caaaaa-caaaaat”), multiple part-word repetitions (eg, “ca-ca-ca-cat”), hurried and jerky repetitions with associated self-awareness and frustration, associated articulation problems, or a home environment with a low tolerance for stuttering or high pressure for verbal communication.21 Normal dysfluency usually improves over time, and parents should be instructed to avoid bringing attention to the dysfluent speech by correcting the child or reminding him to slow down. Parents also should speak more slowly and spend time with the child individually, so that he can express himself in a noncompetitive environment. Encouraging families to take turns and not interrupt conversations during family activities is also beneficial. However, referral to a speech-language therapist is indicated if parents continue to be concerned.


Language Disorders


A language disorder, or specific language impairment (SLI), is an impairment in the ability to understand and/or use words in context, both verbally and nonverbally. The disorder may involve the form of language (phonology, morphology, and syntax), the content of language (semantics), and/or the function of language (pragmatics).14 Language disorders are also classified as receptive disorders (trouble understanding others), expressive disorders (trouble sharing thoughts, ideas, and feelings), or mixed receptive and expressive disorders.


Receptive Language Disorder


Deficits in receptive language almost always occur in conjunction with expressive delays. There are situations in which a child may appear to have an isolated receptive delay, but on careful evaluation, deficits in both areas are present. For example, a child with ASD may appear to have normal or advanced expressive language skills due to extensive use of echolalia, but his or her functional communication delays are similar to the child’s impaired receptive skills. Children with hydrocephalus (congenital or acquired) may have superficially appropriate or advanced expressive language skills but exhibit poor content of expression, known as “cocktail party syndrome.”22 In this case, receptive language lags behind expressive language and is felt to be secondary to hydrocephalus and related effects on the language centers of the brain.


Auditory Processing Disorder


Auditory processing disorder (APD), also known as Central Auditory Processing Disorder (CAPD), is a set of purported functional deficits in the processing of verbal information despite normal auditory thresholds. APD is not universally accepted as a disorder and does not appear in the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5).23 However, it is well described as a disorder by the ASHA. Auditory processing involves recognition and interpretation of verbal information and sounds in the brain. The “disorder” part of APD reflects the situation when something is adversely affecting the brain’s processing or interpretation of the information heard. There is some controversy in diagnosing APD, as some theories suggest APD is likely more due to deficits in working memory and/or a short attention span.24 Children with APD concerns often do not recognize subtle differences between sounds in words, even though the sounds themselves are clear, and they may have difficulty comprehending verbal messages, especially in noisy environments, when others are talking, or when listening to complex information. Auditory processing entails many different processes at all levels of the nervous system, and poor-quality acoustic environments, peripheral ear functioning, behavioral factors involved in listening, and problems with the cochlea, nerve, brainstem, and cortex can all be involved. Empirical research is scarce regarding the validity of modality-specific auditory-perceptual dysfunction. The diagnosis is made using behavioral tests supplemented by electroacoustic measures. Audiological assessment is recommended, and the audiologist will give a testing battery to determine how well the child recognizes sounds in words. A comprehensive assessment with a speech-language pathologist, audiologist, psychologist, and physician is often necessary to diagnose this disorder, as it is often associated with and must also be differentiated from other language, learning, and attention problems. Attention-deficit/hyperactivity disorder (ADHD) and APD especially present overlapping symptomatology, specifically inattention and distractibility. Patients have long-term difficulty with understanding sounds in a noisy environment. Clearly these entities have an overlapping clinical profile, and controversy still exists as to whether they are clinically distinct entities.


Expressive Language Disorder


Expressive language disorders represent a broad spectrum of delays, including developmentally inappropriate short length of utterances, word-finding weaknesses, semantic substitutions, and difficulty mastering grammatical morphemes that contribute to plurals or tense. Signs of weakness in expressive language include circumlocutions (using many words to explain a word instead of using the specific term), excessive use of place holders (“um,” “uh”), nonspecific words (“stuff” or “like”), using gestures excessively, or difficulty generating an ordered narrative.


Mixed Receptive-Expressive Language Disorder


Unless formal language testing using standardized instruments supports the presence solely of an isolated articulation disorder or specific receptive or expressive weakness, a child with a history of “language delays” should be presumed to have had some combination of language understanding and expression weaknesses. A variety of receptive-expressive subgroups have been described, including (1) verbal auditory agnosia (impairment in interpreting the phonology of aural information and resultant limited comprehension of spoken language), (2) phonological-syntactic deficit (extreme difficulty producing language with variable levels of comprehension), (3) semantic-pragmatic deficit (expressively fluent with sophisticated use of words but poor comprehension and superficial use of conversational speech), and (4) lexical-syntactic deficit (word-finding weakness and higher-order expressive skills weakness).25 Table 16.3 outlines the various linguistic features seen with these subtypes of mixed receptive-expressive language disorders.


image


Abbreviations: NL, normal; image, below average; image, significantly below average.


Impairment in both the receptive and expressive language domains raises the possibility of a more serious pathological process, including intellectual disability, ASD and other communication disorders, and deafness. Milder impairment often correlates with less severe forms of these disorders. An audiological evaluation can uncover hearing impairment or auditory processing disorder. Evaluation of a child’s nonverbal problem-solving and adaptive skills can determine whether the child may have an underlying cognitive impairment. If there are concerns related to a child’s social relatedness and social interactions, ASD should be suspected. There is considerable overlap among these underlying causes, especially considering the wide spectrum of severity in each area (Table 16.4).


image


Abbreviations: APD, auditory processing disorder; ASD, autism spectrum disorder; NL, normal; ABNL, abnormal; DQ, developmental quotient; image, below average; image, significantly below average; image, above average; image, significantly above average.


Disorders of Pragmatic Language


Deficits in pragmatic skills involve the inability to use verbal and nonverbal language appropriately for social communication. Successful communication requires one to interpret words that are said in the context of one’s knowledge and experience (linguistic context) as well as the use of words and gestures in the context of interpersonal communication. This involves interpreting the contextual meanings conveyed by words and conversation; one must be able to decipher a speaker’s meaning along with having the linguistic competence to understand what has been said.26 Children with pragmatic language problems may be unable to regulate social interactions or reciprocal body language or appropriately modulate their voice. They may stand too close or too far away from people or have improper voice pitch or volume. They commonly have difficulty initiating, maintaining, or terminating a conversation, modifying a topic for an audience, or including others in conversation.


Pragmatic language disorders are found in diverse clinical populations, including ASD, nonverbal learning disorder, and spina bifida with hydrocephalus.27 Youth with ADHD can also have pragmatic language difficulties consistent with deficits in executive function; deficits are seen in appropriate listener-speaker roles and in using well-organized expressive language.28 Social (pragmatic) communication disorder (SPCD) was introduced in DSM-5, and confusion exists around how this disorder relates to ASD and previous descriptions of pragmatic language impairment. Successful social communication abilities extend beyond pragmatics into the social cognition domain. Criteria include impairments in using communication for social exchange, adaptingcommunication style to the context/needs of the listener, following rules of conversation (eg, taking turns), and understanding implicit or ambiguous language. Diagnosing SPCD is problematic due to inconsistencies in terminology and lack of well-validated, reliable assessment measures. Social communication skills are also subject to significant cultural variation (eg, discourse rules such as taking turns, eye contact, and use of humor), and fewer normative data exist for these behaviors.27


Relationship Between Early Language Delays and Dyslexia


Developmental continuities exist between oral (including speech) and written (reading and written expression) language disorders. Specific language impairments affect fewer children than dyslexia does. By age 5 years, roughly 7.5% of children have oral language skills below age expectations,2 and 25% of these children meet criteria for dyslexia in second, fourth, and eighth grades. Learning to read involves the association between the sounds (phonemes) of spoken language and the symbols (letters [or graphemes]) of printed words. Oral language skills, including phonology, semantics, grammar, and pragmatics, are the foundation for reading. Dyslexia is therefore characterized by reading decoding problems with the core problem based in phonological (speech) processing problems. However, broader language skills, including vocabulary and comprehension processes, are involved and can modify the impact of phonological difficulties. Children with more diffuse language problems typically are at higher risk for reading comprehension deficits. Children with persistent SLI at 8.5 years of age have been shown to have pervasive problems with spelling, word-level reading, and reading comprehension at 15 years of age.29


Evaluation of Children Suspected of Having a Speech or Language Delay


It is important to take parental concerns about speech or language development seriously, as these concerns are valid up to 75% of the time.1 The evaluation of a child suspected of having a speech or language delay should involve a thorough history and physical examination to determine the nature and extent of the problem but also to uncover the etiology whenever possible.


History


It is important to determine whether the delay involves expression alone or both expressive and receptive language abilities. Isolated delays in receptive language are extremely rare. Sometimes a child may appear to have normal or advanced expressive skills due to complex echolalia of entire sentences, but their spontaneous (or functional) language is delayed at least to the same degree as their receptive language (for example, with autism). Parental concerns are often focused on a child’s inability to express himself or herself, and they may not be aware of associated delays in comprehension. Asking parents about any articulation or intelligibility difficulties is important. Inquiry about prenatal and delivery history, results of the newborn hearing screen, hearing loss, multiple ear infections, excessive drooling or difficulty feeding, and delays in other developmental domains will further elucidate an underlying cause. A detailed social history may uncover environmental causes of mild speech delay, including regression after a stressful event (eg, divorce or birth of a sibling), lack of stimulation, or the older siblings and parents overly anticipating the child’s needs. As biological factors contribute to language development, a detailed family history inquiring about speech and language or learning difficulties is important. Twin and family aggregation studies have demonstrated high heritability of language disorders.30


Physical Examination


A simple conversation with the child may be all that is needed to determine the extent of his or her comprehension, expression, and deficits in speech delivery. This includes all attempts to communicate, whether it is verbal (eg, babbling, jargoning, words) or nonverbal (eg, facial expressions, gesturing or pointing, presence of joint attention, eye contact, and body posture). A neurological examination focused on oromotor skills should be completed, especially if there are also feeding difficulties or suspected speech apraxia. The oromotor examination should include imitation of tongue movements in all directions, observance of palatal elevation on phonation, and evaluation of the structural integrity of the oral cavity. Oromotor tone can be assessed by looking at mouth position (ie, open mouth suggesting hypotonia), drooling, trouble drinking from a straw, or difficulty blowing bubbles. Slurred, slow, or hypernasal speech are associated with dysarthria (versus dyspraxia). Inconsistent sound errors and slow pauses between sounds are seen in apraxia/dyspraxia.



Surveillance and Screening


Along with other developmental domains, surveillance of speech and language milestones should be performed at every well-child visit. This includes eliciting and attending to parental concerns, updating attainment of speech and language developmental milestones, determining risk and protective factors, and making accurate observations of the child.31 A 25% delay in milestone attainment is cause for concern and indicates the need for more detailed screening and/or evaluation of speech and language skills. Red flags for delayed speech and language skills are outlined in Table 16.5.


Screening all children for delays in any of the developmental domains should be conducted at periodic intervals and whenever parents voice concerns about their child’s development. The American Academy of Pediatrics has established guidelines for developmental screening and recommends screening for all children at ages 9, 18, and 24 to 30 months,31 or at any time concerns are raised by a caregiver or primary pediatric health care professional, with additional screening for ASD at the 18- and 24-month visits.15

































Table 16.5. Red Flags for Delayed Speech and Language Development


Age


Milestone


6 months


No cooing responsively


10 months


No babbling


12 months


No basic gesturing (waving bye-bye, holding arms out to be picked up)


18 months


No words other than “Mama,” “Dada” No understanding of simple commands No pointing to what he wants


24 months


<50 words No 2-word phrases <50% intelligibility


36 months


No 3-word sentences <75% intelligibility


4-5 years


Not able to tell a simple story


Several screening measures are available for quick evaluation in the pediatric office setting (Table 16.6). Parent-completed questionnaires, such as the Parents’ Evaluation of Developmental Status (PEDS),32 the Parents’ Evaluation of Developmental Status: Developmental Milestones (PEDS:DM),33 and the Ages and Stages Questionnaire-3 (ASQ),34 are good “broadband” screens designed to assess multiple developmental domains. All 3 specifically screen language, and the PEDS:DM offers an assessment-level version that produces age-equivalent scores in expressive and receptive language. Parent questionnaires specifically designed to evaluate language that can be administered in a busy primary care practice include the Receptive-Expressive Emergent Language Test (REEL),35 the MacArthur-Bates Communicative Development Inventories (CDI),36 the Language Development Survey (LDS),37 and the Communication and Symbolic Behavior Scales Developmental Profile Infant-Toddler Checklist (CSBS DP ITC).38 If there are concerns about language and a possible ASD, the CSBS DP ITC screens for social, speech, and symbolic communication in children 6–24 months of age and helps to delineate between communication concerns in those realms. Direct, interactive evaluation measures include the Clinical Linguistic and Auditory Milestone Scale (CLAMS)39 and the Early Language Milestones Scale (ELMS)40 for children from birth to 36 months of age.
























































Table 16.6. Screening Measures for Speech and Language Delays


Parent Questionnaires


Developmental Age Range


Web Address


General Screens


Ages & Stages Questionnaires


0-5 years


www.agesandstages.com


Parents’ Evaluation of Developmental Status (PEDS)


0-8 years


www.pedstest.com


Language-Specific Screens


MacArthur-Bates Communicative Development Inventories (CDI)


0-3 years


www.brookespublishing.com


Language Development Survey (LDS)


18-35 months


www.aseba.org


Receptive-Expressive Emergent Language (REEL)


0-3 years


www.linguisystems.com


Communication and Symbolic Behavior Scales Developmental Profile Infant-Toddler Checklist (CSBS DP ITC)


6-24 months


www.brookespublishing.com


Directly Administered Evaluations


Clinical Linguistic Auditory Milestone Scale (CLAMS)


Up to 36 months


www.brookespublishing.com


Early Language Milestones Scale (ELMS)


Up to 36 months


www.proedinc.com


Parents’ Evaluation of Developmental Status: Developmental Milestones (PEDS DM)


0-8 years


www.pedstest.com


Evaluation of articulation disorders begins with good surveillance. A formula for the expected conversational intelligibility levels of preschoolers talking to unfamiliar listeners is: AGE IN YEARS / 4 x 100 = % understood by strangers:


Child aged 1.0 = 1/4 or 25% intelligible to strangers
Child aged 2.0 = 2/4 or 50% intelligible to strangers
Child aged 3.0 = 3/4 or 75% intelligible to strangers
Child aged 4.0 = 4/4 or 100% intelligible to strangers12


Any child older than 4 years with a speech intelligibility score of less than 66% (ie, less than two-thirds of utterances understood by unfamiliar listeners) should be considered a candidate for intervention.41


It may not be practical to formally assess specific language-based learning problems in a school-aged child in the pediatric office setting. However, a few surveillance questions may help identify the presence of difficulties in language-based learning (see Box 16.1).


Box 16.1. Surveillance Questions for Language-based Learning Problems



1.Does the child have trouble expressing her or his thoughts?


2.Is it difficult for the child to understand or follow directions?


3.Does the child express herself or himself through gestures rather than verbally?


4.Does the child have trouble finding the correct word (word retrieval)?


5.Does the child confuse words that sound alike (eg, “tornado” for “volcano”; auditory discrimination)


6.Does it seem to take a long time for the child to understand directions or answer questions (processing speed)?


7.Does the child seem to have to repeat things (out loud or to self) in order to understand them (processing speed)?


8.Can the child tell you the letter that comes after “s” without going through the alphabet (sequential processing)? Note: The days of the week, months, etc., could also be used.

Oct 22, 2019 | Posted by in PEDIATRICS | Comments Off on Speech and Language Development and Disorders
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