Babies like listening to people speaking to them, preferring this above all else complex sounds and are capable of soliciting, reciprocating or ignoring adult communications as they feel fit.

Robin Balbernie, Child Psychotherapist and Infant Mental Health Specialist

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Babies are biologically primed to make social connections, a straightforward survival mechanism that paves the way to the later attachment relationship. They are soon capable of soliciting, reciprocating or ignoring adult communications as they feel fit. The contours of stress, intonation and the patterns of rhythm and sound (prosody) of ‘parentese’ vary in similar ways according to the parent’s intentions. Across different languages, similar contours convey the same types of meaning such as arousing/soothing, turn opening and closing, approving/disapproving and didactic modelling.

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Nobody who has spent time with babies doubts that they are all set to communicate and interact from birth.  The neonate’s capacity to mimic facial and hand movements immediately tells the parent, ‘I can see and respond to you’, winding them in and softening them up for the next six or so months of sleepless nights and anxious days. Most babies respond almost immediately to speech directed to them if this is done in the right way. Babies are biologically primed to make social connections, a straightforward survival mechanism that paves the way to the later attachment relationship. Simply put, they like listening to people speaking to them in a certain heartfelt fashion, preferring this above all other complex sounds, and are soon quite capable of soliciting, reciprocating or ignoring adult communications as they feel fit. This intuitive style of talking to babies, whose acoustic properties seem to be universal across most cultures (Broesch & Bryant, 2014), is called by many names: ‘parentese’, ‘motherese’ (more common in the past), ‘infant-directed speech’ or just ‘baby talk’. Interestingly, the contours of stress, intonation and the patterns of rhythm and sound (prosody) vary in similar ways according to the parent’s intentions. And across different languages, similar contours convey the same types of meaning such as arousing/soothing, turn opening and closing, approving/disapproving and didactic modelling (Papoušek et al., 1991). Chatting to a baby joins parents across the world.

Parentese

There is a delightful theory that the unique language ability of homo sapiens has its evolutionary roots in our remote hominid ancestors where new foraging strategies, concurrent with less time in the trees and bipedalism, more helpless babies, larger brains and a change of habitat, called for the maternal silencing, reassuring and controlling of physically separate infants who had lost the ability to cling on and so needed to be stashed occasionally to free up mum’s hands and energy to search for food (Falk, 2004). Parentese, the only universal language, thus stands in direct line with the soothing prosody, facial signals and gestures that ensured our ancestors’ reproductive success through soothing babies when necessary, a prelinguistic selective factor that eventually led to the use of words. Chatting to a baby is time travel.

Parentese seems to be more effective when on a one-to-one basis. It has arousing properties and helps capture attention. This is also how many people speak to their pets (Burnham et al., 2002), but whether this is because the pet is a child-substitute or the unconscious wish is to teach the beast to speak is unclear. Compared to normal adult speech, Infant-Directed Speech is marked by a heightened pitch which has a wider range and exaggerated undulating contours. It has a slower tempo with longer pauses and tends to be composed of repetitive vocalizations and is associated with exaggerated gestures. ‘The prosodic patterns of Infant Directed Speech are more informative than those of Adult Directed Speech, and they provide infants with reliable cues about a speaker’s communicative intent’ (Saint-Georges et al., 2013:3). There is a slight difference between mothers and fathers here, with the latter tending to use a narrower frequency range. Most importantly, though, it has a fascinating melody to it: what Malloch (1999) calls ‘communicative musicality’, an inherent organizing principle in parent-baby interactions that facilitates turn-taking and influences the pitch and musical timbre of their vocalisations to each other. 

‘Communicative musicality consists of the elements pulse, quality and narrative – those attributes of human communication, which are particularly exploited in music - that allow co-ordinated companionship to arise’.
(Malloch, 1999:32)

Infant and parent are partners in a musical dialogue. This style of exaggerated speech elongates vowel sounds thus making them easier to tell apart within their native language’s linguistic structure. Chatting to a baby is a mutual melody of love.

Infant and parent are partners in a musical dialogue

Musical mind-sharing

That the communication between parent and baby can be seen as music is hardly surprising given that the baby’s right hemisphere, the place where the neural networks for both relationships and music are mostly located, is the part of the brain that is developing at the greatest rate in the first two years of life; the left hemisphere, where speech processing largely sits, is mostly nascent up until about 18 to 24 months when there is the vocabulary spurt. 

‘The inborn responsive musicality of infants is a rich manifestation of the representation of purposes and emotions evoked by one individual’s brain in the brain of another’
(Trevarthen, 2008:17). 

All parents instinctively sing to their babies and the distinctive style of infant-directed song is recognizable across different cultures (Trehub et al., 1993) although the proportion of rousing or soothing songs does vary, perhaps reflecting differences in caregiving practices. Babies are universally entranced by lullabies, matching bodily movements to the rhythms. Look closely and you will see them conduct. Chatting to a baby is musical mind-sharing.

When a baby arrives in a family, all changes for everyone concerned, so it is fortunate that the new arrival can make herself known.

[Babies] ‘possess rudimentary personal powers that affect their caregivers intimately so that within a short time of birth, a subtle infant-caretaker relationship is established’.
(Trevarthen, 2000:336)

Babies selectively reward parental signalling behaviour. Newborns prefer communications that signal a readiness to interact (direct gaze, baby-directed speech, smiling, etc.); they can appreciate intention.  This applies to pre-term births as well, and baby-directed speech and singing enhances premature babies’ physiological stability (Filippa et al., 2013) and can be used for pain management in a NICU (Ullsten et al., 2018) especially if parents are coached by a specialized music therapist. After only a couple of weeks of life, babies show a distinct preference for parentese over adult-directed speech; this is clearly established by four months, and so begins the cunning and subtle plan of how to train parents through the process of choosing when to respond or not.

‘Desired’ parental behaviour

Babies cannot understand the literal meaning of words, of course, but they usually respond to the exaggerated rhythm, tone, prosody, gestures, facial expressions and postural messages of an attentive adult; this is the act not necessarily the message. They have arrived in the world familiar with their mother’s voice (and that of any siblings at bump height); they can hear muffled noise from about 24 weeks in utero and can recognize the tunes inflicted on them.  Familiar sounds become attractive; they help to organize the post-partum confusion and from then on, language will be a key feature of their interpersonal world and a conduit for culture. Intentions expressed in parentese appear to be understood across different languages (Bryant & Barrett, 2007). By about four and a half months, babies can recognize their own name and by six months, they can recognize the word in their family that designates mother - mum, mummy, mom, Rose, Alice, etc., depending on family use.

Parentese will usually capture an alert and relaxed baby’s attention. Eye contact is a central element here, although having a blind parent does not affect the development of normal social-communication skills and actually benefits visual memory and attention (Senju et al., 2013).  Building on pre-natal experiences, neonates can recognize communication and show sensitivity to temporal sequence and pattern with expectations of social contingency (sharing experiences) and turn-taking appearing at eight weeks.

The engagement involved in ‘serve and return’ communication becomes alluring and by four months babies show a clear preference for adults who do this with them, an aspect of attunement. They have picked up the trick of social smiling during the first three months and this is another reinforcer of ‘desired’ parental behaviour. Chatting to babies creates a feedback that has a dynamic effect on the quality of infant-directed speech, so the parent intuitively adapts to the infant’s abilities, emotional state and immediate needs. This preference for contingent communication extends to the toddler, and a child who has learned to take this for granted (a part of the ‘goal-corrected partnership’ of attachment theory) is more likely to show pro-social behaviour (Thompson & Newton, 2013).  There is no getting away from the fact that mothers talk more to their young children than fathers, and more to their girls than their boys. They also use more supportive speech while fathers are more directive and informing (Leaper et al., 1998), but these may be contextual effects based more on access and role within the family than gender. Chatting to a baby gives him or her felt security.

Native language development

To begin with, babies can respond to every language in the world. Unlike adults, they can discriminate among virtually all phonetic units around, but as they grow and are increasingly exposed to the phonetics of their native language, this capacity soon becomes narrowed down. By the first birthday, the ability to selectively distinguish the different sounds of their native language has been pretty well wired in (Kuhl et al., 2006) based on the selective cues offered by parents, although they will continue to learn to differentiate between these as they grow older concurrent with a decline in non-native speech perception. In an experiment, one group of nine-month-old babies was exposed to a native Mandarin speaker who sang, read to and played with them for twelve session of 25 minutes over one month. At age one, they where being just as good at discriminating sounds in Mandarin Chinese as infants raised in Taiwan, so exposure had reversed the usual decline in foreign language speech perception, whereas the two control groups who had only either watched or heard recordings of the same sessions (rather than being present with the Mandarin speaker in person) were just as duff at this as those infants with no exposure at all (Kuhl et al., 2003). Bilingual families give their children a distinct advantage (Garcia-Sierra et al., 2011).  Chatting to a baby is the scaffolding for language.

Neuroplasticity

Neuroplasticity plays a large part here – neurons that fire together wire together – and the theory of ‘native language neural commitment’ proposes that the baby forms dedicated neural networks that code the sounds and patterns of their home language while also pruning the circuits potentially sensitive to other sounds (use it or lose it) (Kuhl, 2004).  But for this to occur, babies must be directly addressed; neural networks for speech recognition are chosen by chatting. This is supported by experimental data showing significant increase in native language performance over the first year coupled with a decline in non-native perception (Kuhl et al., 2006). Also, as babies listen to speech, Broca’s area and the cerebellum - the brain areas that co-ordinate and plan the motor movements for speaking - become activated (Kuhl et al., 2014) suggesting that babies are rehearsing motor movements for speaking well before expressive language begins and again neuroplasticity will narrow down alternatives.

Babies who are not chatted with are going to fall behind here, with some aspects of language facility perhaps compromised in the long term as babies only learn language through social interaction and their experiences at home are absolutely critical for this (Tamis-LeMonda & Rodriguez, 2014). As an extreme, children who have experienced the deprivation of social isolation as infants never acquire normal language skills (Fromkin et al., 1974). However, in normal development, infants between ages six to eight and ten to twelve months whose mothers used more parentese become better at discriminating the sounds of speech (Liu et al., 2003), and at age two, these infants have larger productive vocabularies (Ramírez-Esparza et al., 2014).  Productive vocabulary is the words the child regularly uses as opposed to those she can understand when used by others.

This advantage continues up to age 33 months (Ramírez-Esparza et al., 2017) by which time the use of parentese is fading. By age three, in all cultures, children can use full sentences to communicate although their skill and vocabulary will vary depending on the early experience they have had. Chatting to a baby changes her mind.

Emotional attunement in action

The process of communication is a process of containment, where the parent lets the baby know that they are prepared to do their best to work out what the baby is feeling and respond appropriately: this may range from comfort and calming to rousing and excitement. The emotional bond between baby and parent is created and reinforced by this mutually pleasurable interaction that serves to coordinate and communicate what each is feeling at any one time, paving the way towards secure attachment. When a baby and parent chat, each partner in the dialogue acknowledges that the other has a mind with something on it that can be shared (not that the baby can conceptualize a mind; she just experiences its working). An attuned parent is able to share experiences with the baby. When doing so, they are the partner who takes most responsibility to shape and hold what is going on since the baby has yet to develop the neurological capacity to do this for herself.

Speaking to a baby, enlisting the ‘proto-musical features’ (Dissanayake, 2008) of mother-baby interaction, is emotional attunement in action.  By this means the parent acknowledges and regulates the baby’s internal state as part of the everyday reciprocal exchanges found in chatting and playfulness.  The factual meaning of the parent’s words can have little effect much before the age of two, but the gist of this right brain to right brain communication is connection and concern. Like the ever-enjoyable mutually improvised playful and physical interactions between mother and baby, chatting provides an experience of regulation through intimacy.  It would be fair to say that, ‘language is simply a subset of music from a child’s view’ (Brandt et al., 2012) that has multiple functions.  ‘The prosodic and melodic contours emitted in lullabies and motherese cause corresponding neural activation contours in the recipient listener [i.e. the baby], experienced as shifts between tension and relaxation’ (Volgsten, 2016:202).  Chatting to a baby, with mutual interest and appreciation, is regulation within a relationship, the fundamental basis of secure attachment. Truly, the medium is the message here (McLuhen, 1965) and the medium is musical.

Chatting to a baby is the start of her capacity for self-control

Good communication and healthy relationships

Chatting, affect attunement and just having fun together are forms of regulatory dialogue that go hand in glove with each other and, when the parent gets it roughly right, these exchanges bring a sense of stability and relief to the infant while building communication skills that will last a lifetime. Relief in the sense that tension or stress is reduced and ennui is met with appropriate stimulation since:

‘Infants respond strongly to the different moods of action games and soothing lullabies, allowing the vital rhythms of their minds and bodies to be excited or slowed into peaceful states’

(Trevarthen, 2008:18).

Healthy relationships are built on good communication. In this intersubjective contact, the engaged parent who is communicating directly with the child does not always get it right in terms of the infant’s need for regulation, but this is OK as the inevitable mistakes provide a chance for interactive repair which in itself is an act of emotional connection and containment. It is important to remember that the neural networks of the baby’s right hemisphere develop first, before those of the left hemisphere where language functions and verbally organized logical thought are predominantly located, and the emotional connection between mother and baby is a right brain to right brain flow of energy and information. That is why all over the world parents predominantly cradle and nurse while holding the baby in the left arm, thus setting up mutual left eye to-and-from right hemisphere communication. Interestingly mothers tend to swop sides when baby is bored and needs a healthy prod. Babies are hardwired to seek a social and emotional partner and communicate from birth. The neuroplasticity that corresponds to the period of infancy, when many areas of the child’s brain are forming connections that may last a lifetime as they adapt to the family environment, means that the  emotional communication that flows through the lilt of parentese will lay the foundation for the developing personality.

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Guidelines for practitioners

Six principles of language learning are laid out in the article by Hirsch-Pasek and Golinkoff (2018). They are:

1. Children learn what they hear most.

2. Children learn words for things and events that interest them.

3. Interactive and responsive environments build language learning.

4. Children learn best in meaningful contexts.

5. Children need to hear diverse examples of words and language structures.

6. Vocabulary and grammatical development are reciprocal processes.

(Hirsch-Pasek, K., Golinkoff, R. M. (2018) ‘Languagizing’ their world: Why talking, reading, and singing are so important. Zero to Three, 38 (3):12-18.)

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