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By Keryn O’Neill, MA, PGCertEdPsych, Knowledge Manager

We all know children need adequate nutrition to enable their body to grow in healthy ways. While this is vital, it is not sufficient for children to grow well. Extending on the concept of nourishing a child’s body, “language nutrition refers to the idea that an environment with sufficient language exposure is critical to…nourish a child’s brain.”1

This article explores some of the ingredients of a nourishing early language environment.  

Why is language development so important?

Right from the beginning, babies are learning a tremendous amount about their world and the people in it. At the same time, they’re developing the many skills they will need to have a meaningful life. The ability to understand and use language is a central component. “Language is a means to communicate, a method to encode and store knowledge, and a superb tool for planning and problem solving. It would be difficult to overstate its role in both social and cognitive development.”2

Oral language is a “key competency that needs to be acquired early in life, so that important interpersonal, academic and vocational goals can be achieved in pro-social ways.”3

Children’s language skills have many and far-reaching implications, during childhood and throughout their lives. There are academic implications, but – perhaps less often thought about – social-emotional effects as well. Effective language use is likely to enable better understanding of social situations, emotions – both one’s own and those of others, and facilitate negotiation of social difficulties with others.4 One study found that children rated as having effective oral communication skills were 19 times more likely to have high mental health competence than children with poor oral communication skills.5 

Language impairment has been associated with an increased likelihood of antisocial or delinquent behaviour in late adolescence. Sometimes this impairment may have gone unrecognised.6 It has been suggested that “the role of language in social regulation, perspective taking and mediating interpersonal exchanges with others may account for the adverse psychosocial outcomes in boys with developmental language problems.”7 It is estimated that 80% of prison inmates have low levels of literacy.8

Early brain development 

Our understanding of the way in which babies acquire language is enhanced by our awareness of the rapid brain development that is occurring, during pregnancy and throughout the first few years of life. 

Language development is an example of the fascinating interplay between a child’s biological makeup and their experiences. Children are biologically prepared to develop language. However, the language/s a child learns are influenced by the languages spoken with them. Whether a child grows up using Te Reo Māori, English, NZ Sign language, or any other language, depends not on their genes, but on the language/s they’ve repeatedly experienced. Just as the particular language they use is influenced by experience, to a large extent so is a child’s proficiency with their language. The developmental period when these experiences are particularly influential, is also the time when their impact may be underestimated. 

Some aspects of brain development have sensitive periods; this means a period of time during which experience plays a particularly important role in influencing the development of that aspect of brain function.9 It is crucial that children receive sufficient input during this time, as once the sensitive period has ended, it can be difficult for them to develop the skills well.10 Some aspects of language development have sensitive periods early in development. While language will continue to develop across the lifespan, its foundations lie in a child’s early experiences.11

A large body of research indicates that both the quality and quantity of a child’s language experiences during their early years, especially before the age of 3 years, are strongly associated with a number of later outcomes. These include their cognitive and language development, social skills, literacy achievement, readiness to start school and academic performance.12 The concept of school readiness is much broader than some may realise; it includes the ability to have positive relationships with teachers and other children, social and emotional skills, such as cooperation, and literacy and numeracy skills.13

The nature of these early language experiences is of critical importance as they lay the foundation for a child’s later abilities.14 While genetic factors play a role in influencing children’s language development, early experiences have a considerable impact on the differences that can be seen between individual children’s levels of proficiency.15

Babies are sensitive to speech prenatally, suggesting they are born ready to learn language.16 One indication of this is that babies’ first cries reflect the language they’ve experienced in utero.17

Ingredients of a Nutritious Language Environment 

Quantity of Language 

In the same way that children need sufficient quantity of food to meet their nutritional needs, so too does the amount of language interaction matter. 

Whilst a minimally interactive environment will likely be sufficient to trigger basic language development, “considerable individual differences exist in typical language learning circumstances that, in turn, affect the quantity and quality of the linguistic input children receive.”18 

The seminal and much-cited work of Hart and Risley over 20 years ago provides one illustration of this. They found that the level of vocabulary and the verbal ability of a child at 2 years was strongly related to the amount of talking their parents did with them from birth. Those who were spoken to more performed better.19

Differences between groups based on socioeconomic status were found. Children from families on welfare heard, on average, around 600 words per hour, compared with an average of over 2,000 words per hour for children from professional families.20 This difference, when accumulated over the first three years of life has become known as the thirty-million-word gap.21 This gap corresponded to large differences in children’s vocabulary size when they began school; with vocabularies of about 5000 words for children raised in poverty, and around 20,000 words for those from families of higher income.22 The gap continued, as they also found that the variety and number of words parents used with their children before 3 years were related to their receptive language skills at 9 years.23 

More recent examples of the impact of early language interactions can be found in research conducted with babies born prematurely and spending time in a Neonatal Intensive Care Unit (NICU). Babies who received higher amounts of parental talk while in the NICU were likely to have improved language and cognitive scores at 7 and 18 months (corrected age).24

A review of multiple studies found that in all cases, the quantity of language input predicted the child’s later vocabulary.25 There was significant variability in quantity of adult speech, differences as large as 18-fold.26 Although variation in caregiver speech was seen between socioeconomic groups (as in Hart & Risley’s study), large differences were also noted within the same SES group. And at all levels of education.27

Serve and return

As we’ve already seen, the amount of language babies and children hear is important for their development. But there’s so much more to nutritious early language input than the sheer quantity of words spoken to a child.

Another feature of a nutritious early language environment is the level of responsiveness of parent and whānau to a baby or young child. This has been described in a number of ways, including the notion of “serve and return”. Much like a (decent!) game of tennis, the baby reaches out to interact with those around them (a serve) and a responsive adult recognises this as communication, and responds (return), and so it continues. This “‘serve and return’ interaction between parent and baby … builds and strengthens brain architecture and creates a relationship in which the baby’s experiences are affirmed and new abilities are nurtured.“28

When the adult’s returns are responsive to the baby’s emotions and needs, their interactions are developing communication, language, social and emotional skills. They are also contributing to the development of a secure attachment relationship between child and parent. Using the language of emotions further helps children in understanding and ultimately being able to regulate their emotions. For example, children whose parents accurately comment on how they are feeling are more likely to develop a secure attachment with their parents.29

This just might be the epitome of multitasking!  By engaging in serve and return interactions with babies and children, adults in their lives are contributing to several important areas of their development, at the same time!

Multiple studies have found that speech that’s contingent on the vocalisations or attention of children improves both receptive and expressive vocabulary. In other words, parent language is most beneficial when it’s co-ordinated with, and appropriate to, the child’s own communication.30 This is the case for children at risk of, or having, language/cognitive delays, as well as typically developing children.31 Contingency is important during infancy and into toddlerhood,32 however parents vary greatly in terms of how much they respond to their child’s own communication.33

One study compared two groups of children. The first group had mothers respond immediately to their child’s communication (the contingent group); the second group received the same amount of talking from their mother, but not in response to the child’s own communication (the non-contingent group).34 Children in the contingent group vocalised more, and more maturely, than the non-contingent group. This indicates that it’s not just the amount of talking babies hear that’s important, but whether they are having back-and-forth conversations too.

Many studies indicate that language needs to be shared with a child for them to benefit from it; being exposed to media and background conversations do not help children’s language development as they don’t enable the necessary ‘serve and return’ of conversation.35 When parents respond to their child, they are doing so through many modalities, not only their speech. They tend to match physical and verbal cues, for example pointing, touching or looking at objects whilst talking about them.36 This helps children’s learning as they’re more likely to learn words for things that they are looking at.37

Language serves a social function; which infants appear to instinctively know. As early as their first month, infants respond more vocally when their parents are present and are talking with them.38

Depending upon their own early experiences and other factors, some parents may find this interaction with their baby does not come easily and may benefit from support as they learn to effectively interact with them.39

Parentese

Most parents naturally change their speech when talking with their infants, using what is known as “motherese,” “parentese,” or known in the research as Infant-Directed Speech(IDS).  

Qualities of parentese include: talking more slowly, greater repetition, shorter phrases, extended vowel and consonant sounds, and a higher and more varied pitch.40 Mothers typically show exaggerated facial expressions and maintain eye contact longer when interacting with their baby.41 It is also more musical and emotionally expressive than adult-directed speech.42 

Parentese uses real words and sentences, as opposed to ‘baby talk’ which merely imitates the sounds made by the infant.43

Parentese occurs across cultures and languages,44 however, its features differ across language and cultural contexts.45 Both mothers and fathers tend to change their tone when talking to infants.46 The specific ways in which mothers and fathers change their speech differs, with some suggesting that “fathers play a special role in facilitating language learning in infants and toddlers by using more complex speech than mothers”.47 By 4 years of age, children adjust their own speech in similar ways when interacting with 1- and 2-year olds, as well as in pretend play with baby dolls.48

Many studies indicate that from their first weeks after birth, and in some cases, as newborns, infants can differentiate between infant-directed and adult-directed speech and singing, and prefer listening to infant-directed versions.49 It’s thought that both the structural and emotional properties help attract and sustain early communication. Parentese captures infant’s attention more readily than adult-directed speech; they are more attentive and responsive to parentese and their brains are able to process it more easily than regular speech.51 The slower speech and hyper-articulated vowels seem to help young children pick out words from sentences, with one study finding toddlers were slower to look at images of the target word when parentese was not used.52

There are a number of ways in which infants respond differently to IDS, compared with ADS. Use of parentese seems to indicate to an infant that what is being said is directed towards her.53 In other words, IDS is more likely to be perceived as an attempt to communicate, and is more effective at attracting an infant’s attention towards their parent. Infants are more likely to respond to, and imitate, an adult using parentese; this active participation in the communication is a crucial component of the language learning process.54 Being spoken to in this way encourages an infant to spend longer looking at the adult they’re communicating with,55 and with greater focus, which in turn enables more effective interactions.56 

Studies of neural activity found infant’s brains responded with increased activation when listening to IDS, compared to ADS,57 suggesting that the infant brain is particularly sensitive to the richer auditory input of parentese.58 The level of responsiveness to parentese changed over time, indicating that with increasing age and language proficiency, this aspect of young children’s communication input becomes less relevant.59

Parentese appears to enhance word learning,60 with infants exposed to more parentese having larger vocabularies later.61 This may be at least partially due to the way in which parentese emphasises particular words being spoken, thereby helping later word recognition.62

Active Communicators from Birth

A baby’s first words are often much celebrated, however, this is far from being their first communication. From moments after birth a baby has skills and behaviours that enable them to communicate with others. These abilities undergo dramatic change over their first year by the end of which their first words have typically been heard.63 It’s important that parents learn to read what their baby’s signals mean and respond accordingly.64 Having parents and other whānau respond in this way helps a baby to feel understood and important, and through many repetitions they also gradually develop new skills.65

It’s worth remembering that for all parents, learning to interpret their baby’s communication is a process of trial and error; some mistakes are inevitable. 

Babbling, pointing and gesturing are important prelinguistic skills used by babies to communicate with those around them.66 Babbling provides an opportunity to practice the sounds of their own language.67 By looking at, or touching objects babies are letting those around them know where their interests lie, and this enables shared attention with those around them.68 

Babies’ ability to understand words develops earlier than their ability to say them. While most 8-month-olds are not saying any words, they can understand an average of 25 words.69

Gesture

The use of gestures, especially pointing, marks an important step in communication development.70 In fact, babies who engage in more pointing and gesturing have been found to understand more words a few months later. When adults recognise these behaviours as communication and respond accordingly, it encourages a young child’s developing skills and boosts their language development.71

It’s important to differentiate between spontaneous gestures initiated by the child themselves, and those they are taught.72 Parents wanting to support their child’s development may have come across some of the many commercially available baby-signing programmes,73 and associated claims about their cognitive and socio-emotional benefits.74 Despite many claims that research supports the benefits of baby-sign, in fact such statements have been based on opinion in the vast majority of cases.75

The idea that there are advantages for young children learning baby sign language has been around for over two decades but there has been relatively little research investigating this. A systematic review of available research was conducted, looking at the effectiveness of baby sign language for typically developing, hearing infants under the age of 3 years. The review concluded that baby-sign neither benefits nor disadvantages typical child development.76 It’s important that parents who do chose to use baby-sign are aware that the claimed benefits are not supported by available research. 

Changing Needs

There’s a fascinating mutual feedback loop operating when parents are responsive to their young child’s communication. As described earlier, infants’ communication is influenced by that of their parents; parents in turn change their communication in response to their child’s developing skills.77 For example, mothers tend to respond more to new words spoken by their 2-year-olds, than to words they’ve used for a while.78 Parent responses to their child’s vocalisations tend to increase between 14 and 24 months, at the same time as a decrease in response to their child’s gesturing.79 

Collectively, these studies indicate that parents “up the ante” by responding in new ways to emerging skills in infants.80 The way in which mothers interact with their children changes as children develop and become increasingly active communication partners.81

Quality of Language

Parents talking with children is most likely to enhance their language development when their language is “just challenging enough for the child”; not so simple that the child doesn’t learn anything, but not so complicated that they become confused or disinterested.82 Parents’ expansion of their child’s communication contributes to their lanaguge development.83 This might involve repeating some of what the child said and adding new information; best done as a natural part of the back and forth conversation, rather than interrupting the natural flow of the conversation.84

Other aspects of parental communication that have been associated with positive outcomes for children include the diversity, or number of types, of parental vocabulary.85 A variety of everyday experiences provide opportunities for this to happen. Hearing the same words or concepts in different contexts also assists young children’s learning.86 For example, water can be found in a drink bottle, the bath, at the beach, and in a puddle after the rain. When parent or whānau talk about ‘water’ in a number of these or other contexts, they are helping develop a much richer understanding, than a child who may only hear “Drink your water”.

Parents provide a richer language experience for their child when they use the language they are most comfortable speaking. In doing so, they are likely to be more fluent, use more complex and grammatically correct language, and increase the amount of language they are sharing with their child.87 This will benefit their child’s language development more than using a language with which they are less fluent, even when that is the dominant language.88

A few cautionary words

While the hope is that parents will mostly be responsive to their infants, this doesn’t mean that they should expect to be constantly responsive. There are likely to be daily periods of delayed or no response when the parent is attending to other tasks.89 In fact, some of these lapses in communication, when they occur in the context of largely nurturing and responsive relationships, can provide opportunities to develop a child’s resilience.90 This occurs through a child’s exposure to small, manageable incidents of stress, which are then resolved through reconnecting with their parent.

All children need sufficient interaction with loving adults, particularly during their first few years to develop well, including but not limited to, the area of their language development. However, this does not mean expecting children to master skills for which they are not developmentally ready; doing so may not only waste time and resources, but also potentially harm their brain development through heightened levels of stress for the child.91

The importance of the early years for brain development is sometimes used to entice parents and whānau to part with their hard-earned money; purchasing items or attending classes claiming to enhance their child’s development. It’s important that parents realise that none of this is necessary. However, “everyday interactions for most infants pose a world rich with opportunities to explore and to stimulate cognitive growth.”92 Just because it’s free, doesn’t make it less valuable.

Conclusions

The quantity and quality of the early language children experience has significant implications for their development. This is particularly true in the first three or so years of their life. Nutritious language experiences during their early months and years provide a strong foundation for later learning and development, across many areas.

Babies are born ready to communicate with the important people in their world. They are also incredibly keen to learn. Parents and whānau who interpret and respond to their early communication, as they go about ordinary, everyday activities, are giving their child an incredible gift. A gift that is likely to be passed down to future generations.

Footnotes

  1. Weldon, 2014, cited by Zauche et al., 2016, p.319
  2. Warren, 2015, p.2
  3. Snow & Powell, 2012, p.1
  4. K. E. Nelson et al., 2010
  5. Goldfeld et al., 2017
  6. Bor et al., 2004, Brownlie et al., 2004,and, Smart et al., 2004, cited by Snow & Powell, 2012
  7. Snow & Powell, 2012, p.3
  8. Shaw, 2015
  9. National Scientific Council on the Developing Child, 2007
  10. Knudsen, 2004
  11. Arshavsky, 2009; Knudsen, 2004
  12. K. E. Nelson et al., 2010; Shaw, 2015; Zauche et al., 2016; Zimmerman et al., 2009
  13. National Scientific Council on the Developing Child, 2004
  14. Niklas, Cohrssen, & Tayler, 2016
  15. Oliver & Plomin, 2007, cited by Weisleder & Fernald, 2013
  16. Niklas et al., 2016; Zauche et al., 2017
  17. Mampe et al., 2009, cited by Bruderer et al., 2015
  18. Linebarger & Walker, 2005, p.625
  19. Hart & Risley, 1995, and Risley & Hart, 2006, cited by Davies, 2011
  20. Hart & Risley, 2003
  21. Hart & Risley, 1995, cited by Zauche et al., 2017
  22. Hart & Risley, 1995, cited by Rodriguez et al., 2009
  23. Hart & Risley, 1995, cited by Dodici et al., 2003
  24. Caskey et al., 2014
  25. Zauche et al., 2016
  26. Hurtado et al 2008, and Weisleder & Fernald 2013, cited by Zauche, et al., 2016
  27. Caskey et al., 2014
  28. National Scientific Council on the Developing Child, 2004, p.2
  29. Meins et al., 2001
  30. Bornstein et al., 2008, and, Roseberry et al., 2014, cited by Taumoepeau, 2016
  31. Taumoepeau, 2016; Zauche et al., 2016
  32. Landry et al., 2001, 2003, cited by Zauche et al., 2016
  33. Taumoepeau, 2016
  34. Goldstein et al., 2003, cited by Kuhl, 2004
  35. Montag et al., 2015; Weisleder & Fernald, 2013; Zauche et al., 2016
  36. Tamis-Lemonda et al., 2013, cited by Tamis-LeMonda et al., 2014
  37. Yu & Smith, 2012, cited by Tamis-LeMonda et al., 2014
  38. Cassel et al., 2013, cited by Spinelli et al., 2017
  39. Dodici et al., 2003
  40. Music, 2011; Kuhl, 2004, cited by Parsons et al., 2010; Zauche et al., 2016
  41. Eibl-Eibesfeldt, 1989, cited by Simpson & Belsky, 2008
  42. Mithen, 2006, cited by Music, 2011
  43. Zauche et al., 2017
  44. Zangl & Mills, 2007
  45. Broesch & Bryant, 2017; Schreiner & Mani, 2017
  46. Fernald et al., 1989, cited by Spinelli et al., 2017
  47. Broesch & Bryant, 2017, p.4
  48. Sachs & Devine, 1976, and, Shatz and Gelman, 1973, cited by Soderstrom, 2007
  49. Soderstrom, 2007; Tsang et al., 2017; Zangl & Mills, 2007
  50. Pegg et al., 1992, cited by Tsang et al., 2017
  51. Corbeil et al., 2016; Gilkerson & Klein, 2008
  52. Song et al., 2014, cited by Zauche et al., 2016
  53. Saint-Georges et al., 2013, cited by Schreiner & Mani, 2017
  54. Golinkoff et al., 2015, cited by Spinelli et al., 2017
  55. Cohen et al., 2013, and Kaplan et al., 1995, cited by Spinelli et al., 2017
  56. Schachner & Hannen, 2011, cited by Spinelli et al., 2017
  57. Naoi et al., 2012, cited by Spinelli et al., 2017; Zangl & Mills, 2007
  58. Fernald & Kuhl, 1987, cited by Zangl & Mills, 2007
  59. Zangl & Mills, 2007
  60. Graf et al., 2013, and, Song et al., 2010, cited by Schreiner & Mani, 2017
  61. Schreiner & Mani, 2017; Spinelli et al., 2017
  62. Zangl & Mills, 2007
  63. Goldstein & Schwade, 2008
  64. Bornstein et al., 2016
  65. National Scientific Council on the Developing Child, 2004
  66. Bidgood, 2016; Warren, 2015
  67. Bidgood, 2016
  68. Bidgood, 2016; Warren, 2015
  69. Bidgood, 2016
  70. Bidgood, 2016
  71. Bidgood, 2016
  72. Howard & Doherty-Sneddon, 2014
  73. Zammit & Atkinson, 2016
  74. Howard & Doherty-Sneddon, 2014
  75. Howard & Doherty-Sneddon, 2014; L. H. Nelson et al., 2012
  76. Fitzpatrick et al., 2014
  77. Tamis-LeMonda et al., 2014
  78. Masur, 1997, cited by Tamis-LeMonda et al., 2014
  79. Tamis-Lemonda et al., 2013, cited by Tamis-LeMonda et al., 2014
  80. Tamis-LeMonda et al., 2014, p.124
  81. Taumoepeau, 2016
  82. Zimmerman et al., 2009, p.347
  83. Taumoepeau, 2016
  84. Clark, 2007, cited by Warren, 2015
  85. Cristofaro & Tamis-LeMonda, 2012; Taumoepeau, 2016
  86. Montag et al., 2015
  87. Zauche et al., 2016
  88. Paradis & Jia, 2017
  89. Stenberg, 2017
  90. DiCorcia & Tronick, 2011
  91. National Scientific Council on the Developing Child, 2007
  92. Nevills & Wolfe, 2009, p.48

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