Emergent literacy including language development

INTRODUCTION — Literacy acquisition begins long before children encounter formal school instruction. During their early years, children acquire knowledge and skills that are literate behaviors in informal settings. The term emergent literacy [1-3] emphasizes that:

●Literacy development is an ongoing process

●All aspects of literacy develop simultaneously

●There is a natural hierarchy to the stages of development

●Language and literacy acquisition share important features

DEFINITIONS

Domains of communications — Communication has nonverbal and verbal domains. Nonverbal communication includes body language, gestures, and signing. Verbal communication occurs in oral or written modes and has three components [4]:

●Receptive language – reception of sensory information

●Expressive language – motoric expression; involves articulation, voice, fluency

●Linguistics – CNS processing of sensory and motor functions and formulating language

Language parameters — Language has four components [5]:

●Phonologic – Speech sounds, phonemes

●Semantics – Vocabulary, word meaning

●Syntax – Grammar, combining words into sentences

●Pragmatics – Use in context to communicate effectively

LITERATURE REVIEW — The development of language and the attainment of literacy skills in children occur along a continuum that has a hierarchy of stages of development, including the acquisition of oral language, reading, writing, and spelling skills [2,3,6,7].

●Most children progress toward language competence through a series of similar stages despite differences in cultural and linguistic backgrounds [2].

●Children pass through these stages at different ages and in a variety of ways [1]. A child may be at a different level of competency for each domain of literacy.

●Literacy acquisition begins when children learn to recognize letters as unique patterns and comprehend that print, not pictures, carries the message. Next, children become aware that letters provide clues for reading, and they may recognize some words. During the third stage of literacy development, children realize sounds are determined by letters and words are created by putting sounds together. In the most advanced phase of development, children begin to immediately recognize morphemic parts of words [2,3,6,7].

●The acquisition of literacy requires not only competent oral language skills, but an understanding of the relationship between oral and written language [8]. Literacy and language are related in important ways. Both occur in a social context for the purpose of communication. Characteristics of caregiver-child interactions that support language acquisition also facilitate early reading and writing development. Oral language competence is highly correlated with success in learning to read [2,9].

Environment — A child's early literacy environment plays a critical role in the emergence of literacy [10-12]. Caregiver-warmth and sensitive responsiveness (ie, prompt and appropriate caregiver response to the child's signals) are key elements of the early literacy environment. Young children learn many important concepts about reading before going to school [6,13-15]. Their early experience with books and reading contributes to their later success or failure in learning to read [15].

Children enter school with different knowledge levels and learn to read at different rates. Those who enter school with the least knowledge of beginning reading skills are at academic risk [15].

Risk factors for poor reading skills among children in kindergarten include [16-18]:

●Living in poverty

●Living in a single-caregiver household

●Being from a non-English-speaking family

●Lower caregiver education level

Reading ability may predict change in problem behaviors during the primary school years [19].

Frequency — The frequency of early literacy experiences, including listening to stories, in preschoolers is directly associated with [20,21]:

●Teacher ratings of oral language skills at five years of age and reading comprehension at seven years of age [22]

●Success on reading achievement tests in second grade [23]

●Vocabulary, syntax, letter recognition, and print awareness [24]

The frequency of caregiver-child reading increases when caregivers receive books and encouragement to read at health supervision visits [25-27]. Caregivers in families who are involved in clinic-based literacy promotion projects (eg, Beginning with Books or Reach Out and Read) are more likely to read regularly to their children and to describe reading as a favorite caregiver-child activity [28-31]. The frequency of caregiver-child book sharing in first-generation Hispanic immigrant families also is related directly to caregiver reports that they read frequently to themselves [32]. Less-frequent caregiver-reported shared reading (≤4 days per week) has been associated with higher risk of social-emotional problems in young children presenting for primary care, highlighting the potential relational and social-emotional benefits of shared reading [33].

The reports of the effects of clinic-based literacy programs on language and literacy development vary slightly [34-37]. However, most studies demonstrate an increase in the expressive and receptive language scores of children who received books and whose caregivers received modeling and encouragement to read aloud during health maintenance visits. Children in prekindergarten classes who were given books and encouraged to share them with their caregivers had greater word knowledge, spelling, and story-reading ability at the end of kindergarten than did those who did not receive books [15]. In addition, fewer of the children who were given books were in low reading groups at the end of first grade.

Quality — In addition to the frequency of early literacy experiences, the quality of the caregiver-child interaction and the child's environment affect literacy development [10,11]. Children need access to a variety of reading materials and need to observe diverse, developmentally appropriate literate behaviors to achieve their literacy potential. As Marilyn Jager Adams states, "it is not just reading to children that makes the difference, it is enjoying the books with them and reflecting on their form and content" [38].

Considerable interaction exists between adult reading style and the child's skill level. Various reading styles benefit different literacy skills depending upon the child's level of development. A lower-demand reading style (describing and labeling) may be most appropriate for advancing vocabulary development with younger or less skilled learners, whereas a higher-demand, uninterrupted style (discussion before and after the story) may be most beneficial for older or more advanced children [39].

●In observational studies, caregivers do alter the interactional style of reading depending upon the child's level of communicative competence [40,41].

●Children whose caregivers were instructed to increase open-ended questions, expand on replies, and encourage discussions of function and attributes had higher expressive language scores and longer mean utterance than did children whose caregivers did not receive this intervention [42].

●The type of book that is read affects the teaching strategy of caregivers; greater participation from caregivers and children is elicited when expository books (collections of pictures or labels), rather than narrative books (stories), are read [41]. Observational studies suggest that although electronic books increase engagement and attention [43], they are associated with more frequent social control behaviors (eg, pushing a hand away, grabbing the book, turning away from the reading partner) and less social reciprocity (eg, conversational interaction collaboration) than print books [44,45].

Demographics — Researchers have reported variable effects of socioeconomic status, ethnicity, and caregiver education on emergent literacy [10,15,46-48].

●Some researchers report that low socioeconomic and less educated caregivers may be adequate teachers for their child's present level of development but less knowledgeable about language and cognitive development [49], less sensitive to the changing needs and capabilities of their children [46], and less able to foster the acquisition of prereading skills [15]. In a large cohort study, lower socioeconomic status was associated with less frequent caregiver reading and fewer books at home [10].

Pediatric health care providers can help low socioeconomic status caregivers foster their infants' language and cognitive development by taking advantage of caregiver confidence and providing knowledge and effective strategies [49]. (See 'Suggestions for caregivers' below.)

●Other researchers associate greater child-centered literacy orientation with two-caregiver families, higher adult-to-child ratios, households speaking only English, ownership of more than 10 children's books, and caregivers who read a few times per week themselves [47].

●Still other researchers have found a wide range in the quantity and nature of literacy materials present in the homes and a large variation in the utilization of these materials, rather than a distinct difference in literacy practice by ethnicity or educational level of low-income families [48].

NORMAL LANGUAGE DEVELOPMENT — Language and literacy skills develop along several parameters simultaneously, over an extended period of time, in a predictable order, and at a predictable rate. The achievement of isolated milestones may be misleading. As an example, a child may have a large vocabulary because of a great ability to imitate or memorize yet be incapable of using these words appropriately in conversation. The normal milestones in language and literacy development are shown in the graphics (figure 1 and table 1) [50-56].

DELAYED LANGUAGE AND LITERACY DEVELOPMENT — Developmental language delays or disorders occur in 5 to 10 percent of preschool children. They can involve aspects of expressive, comprehensive, or total language development. (See "Etiology of speech and language disorders in children", section on 'Language disorders'.)

Delays in language and literacy development do not occur because the child is lazy, older siblings speak for them, the child lives in a bilingual environment, or the child is a twin [53]. Children do not "outgrow" these problems and should be referred as soon as possible for evaluation and intervention. (See "Evaluation and treatment of speech and language disorders in children".)

Red flags — Red flags for language or literacy problems are numerous and include [5,56,57]:

●Caregiver concern regarding hearing, abnormal speech production, or comprehension

●No babbling by nine months

●No first words by 15 months

●No consistent words by 18 months

●No word combinations by 24 months

●Speech is difficult for caregivers to understand at 24 months

●Speech is difficult for strangers to understand at 36 months

●Deficient lexicon – Slow growth of vocabulary

●Dysfluencies (stutters) consist of more than tension-free whole word repetitions

●Child is frustrated by communication difficulty

●Child is teased by peers for "talking funny"

●Child avoids talking situations

●Child acquires vocabulary and sentence structure but does not use language appropriately for communicative purposes

●Language is unusual or confused, or ideas are not expressed clearly

●Child cannot follow instructions without supplemental visual cues

●Loss of milestones

●Poor memory skills at five to six years of age: inability to learn colors, numbers, shapes, alphabet

●Decreased linguistic awareness at five to six years of age: phonemic awareness, segmentation, syntax, concepts of print

Etiology — The causes of delayed language development are numerous and include issues like social deprivation, anatomic structural defects, oral motor or neuromotor dysfunction, hearing impairment, and neurocognitive delays. The evaluation and management of children with delayed expressive language development are discussed separately. (See "Expressive language delay ("late talking") in young children", section on 'Etiology'.)

Prognosis — Early identification and intervention for children with abnormal language or literacy development are critical. Children whose speech and language impairment persists beyond five years of age may continue to have difficulty into adulthood. As examples:

●Children with a history of phonologic disorders perform more poorly than do controls on writing tasks; those with a language disorder in addition to the phonologic disorder have the greatest difficulty [58].

●Seventy-one children with speech-language impairment at age four years were followed into adolescence [59]. Those whose speech and language impairment persisted at age five (56 percent) were at high risk for language, literacy, and educational difficulties throughout childhood and adolescence. By comparison, when the early speech and language impairment resolved by age five (44 percent), the outlook for spoken language development was better, but literacy skills were weak because of residual phonologic processing deficits.

●Another prospective longitudinal trial compared children with speech and language impairment at age five with age-matched controls; high rates of communication difficulty remained at 12 and 19 years of age [60]. However, only approximately 50 percent of the subjects in this study received treatment, usually during early years.

●Investigations of the association of language ability and psychosocial development have mixed findings. In one large cohort study, children with poor early receptive language skills experienced more disadvantaged socioeconomic circumstances in early childhood and more behavior and psychosocial adjustment problems in the transition to adulthood than children with normal language skills [61]. In another large cohort study, late-talking children had increased internalizing and externalizing behaviors at age two years compared with control toddlers but were not at increased risk for behavioral and emotional problems at age 5, 8, 10, 14, or 17 years [62].

BILINGUAL LANGUAGE DEVELOPMENT — Questions often arise about the language development of children reared in bilingual environments. Bilingualism is the ability to speak two languages [63]. Early research that suggested bilingual children were less intelligent than were monolingual children is incorrect. Learning two languages at once does not harm a child's cognitive abilities [64-66]; rather, it enhances them [67-70]. An initial stage of confusion, code-mixing, and comprehension-building for young bilinguals may occur but resolves [71]. At 24 to 30 months of age, bilingual children may intermix vocabulary and syntax from both languages, but vocabulary size, intelligibility, and length of utterance are normal. By 36 months of age, they become fluent bilingual speakers [53]. One should note that single-language scores in one language may not accurately reflect the child's abilities, and direct comparisons across languages and different writing systems are precarious.

Improving access to bilingual books benefits both children and their families [72]. Bilingual books enhance bilingual language development for the child, improve English as a second language for the caregivers, and demonstrate respect across cultures and the value of traditions. Pediatric health care providers can play a key role in supporting caregivers raising bilingual children through encouraging shared bilingual reading experiences [73].

SUGGESTIONS FOR CAREGIVERS

●Speak slowly and succinctly

●Label objects

●Repeat, repeat, repeat

●Ask open-ended questions

●Expand on the child's conversation

●Correct positively – Rephrase, repeat, relabel

●Use interactive games and humor

●Encourage the child

●Tell stories to each other

●Limit television viewing time

●Visit the library regularly

●Dialogue your activities: talk about what you are doing, even if it is baking a cake

●Read every day [74,75]

The American Academy of Pediatrics has developed a Literacy Toolkit that includes information for caregivers about selecting books and sharing books with children of various ages and a policy statement for literacy promotion [74].

In a systematic review of 59 randomized and 17 nonrandomized clinical trials in 5848 children <6 years of age who had or were at risk for language impairment, caregiver-implemented interventions (eg, naturalistic responding to child communication, asking questions and having discussions while reading with the child) were moderately associated with improved child communication, engagement, and language outcomes [76].

SUMMARY

●Communication has verbal and nonverbal domains. Verbal communication includes receptive language, expressive language, and linguistics. Nonverbal communication includes body language, gestures, and signing. (See 'Domains of communications' above.)

●The development of language and literacy occurs along a continuum that has a hierarchy of stages, including the acquisition of oral language, reading, writing, and spelling skills (figure 1 and table 1). The development of literacy requires competent oral language skills and an understanding of the relationship between oral and written language. Oral language competence is highly correlated with success in learning to read. (See 'Literature review' above and 'Normal language development' above.)

●A child's early literacy environment plays a critical role in the emergence of literacy. Early experience with books and reading contributes to subsequent success or failure in learning to read. (See 'Environment' above.)

●The frequency of early literacy experiences, including listening to stories, in preschoolers is directly associated with oral language skills, reading comprehension, and reading achievement. The frequency of caregiver-child reading increases when caregivers receive books and encouragement to read at health supervision visits. (See 'Frequency' above.)

●There are a number of things that caregiver can do to promote their child's early language and literacy development. These include speaking slowly and succinctly, asking open-ended questions, expanding on the child's conversation, telling stories to each other, limiting television time, visiting the library, telling the child what they are doing, and reading every day. (See 'Suggestions for caregivers' above.)