What is Language?

Our vast intelligence also allows us to have language, a system of communication that uses symbols in a regular way to create meaning. ^[1]

Human language is the most complex behavior on the planet and, at least as far as we know, in the universe. Language involves both the ability to comprehend spoken and written words and to create communication in real-time when we speak or write. Most languages are oral, generated through speaking. Speaking involves a variety of complex cognitive, social, and biological processes including the operation of the vocal cords, and the coordination of breath with movements of the throat, mouth, and tongue.

Other languages are sign languages, in which the communication is expressed by movements of the hands. The most common sign language is American Sign Language (ASL), commonly used in many countries across the world and adapted for use in varying countries. The other main sign language used in Canada is la Langue des Signes Quebecoise (LSQ); there is also a regional dialect, Maritimes Sign Language (MSL).

Communication using sign language.^[2]

Although language is often used for the transmission of information (“turn right at the next light and then go straight,” “Place tab A into slot B”), this is only its most mundane function. Language also allows us to access existing knowledge, draw conclusions, set and accomplish goals, and understand and communicate complex social relationships. Language is fundamental to our ability to think, and without it, we would be nowhere near as intelligent as we are.

Language can be conceptualized in terms of sounds, meaning, and the environmental factors that help us understand it. A phoneme is the elementary sounds of our language.  A morpheme is the smallest units of meaning in a language. Syntax is the set of grammatical rules that control how words are put together, and context is the element of communication that is not part of the content of language but helps us understand its meaning. ^[3]

Finally, human language is unique on the planet because it has the qualities of generativity, recursion, and displacement:

• Generativity – Human language is generative, which means that it can communicate an infinite number of ideas. This is because Phonemesit is combinatorial: words can be combined in different orders to create different larger meanings of a sentence. Animal communication does not have this freedom; animals communicate within closed systems, with limited possible ideas to communicate. Birds may have different chirps to signify danger or the location of food, but they cannot combine those to convey a novel meaning.
• Recursion – Human language is recursive. This means that we can put words, phrases, and sentences inside of themselves without limits. For example, we can say the sentence “Mark likes anchovies.” But we can also put that sentence inside of a sentence: “Carol thinks that Mark likes anchovies.” Then we can put that sentence inside of another sentence: “Greg said that Carol thinks that Mark likes anchovies,” and on and on forever. Obviously, the recursive abilities of language are constrained by the limits of time and memory. But in theory, because units of human language have the ability to be self-containing, we could have an infinite sentence. Animal communication does not have this same flexibility.
• Displacement (in language) – Human language has displacement. This means that through the power of language, we can refer to things that aren’t present spatially or temporally. This is obviously a useful trait (it allows us to ask questions like “Where did I leave my wallet?”), and it is one that is largely missing from the animal kingdom. Bees actually do have limited displacement in their communication: They perform a waggle dance to communicate to other bees the location of the most recent food source they have visited. However, there is no temporal nuance beyond this. Ants and ravens also have limited displacement systems.

Human language is also modality-independent—that is, it is possible to use the features of displacement, generativity, and recursion across multiple modes.  Speaking is the auditory form of language, but writing and sign language are visual forms. There are also tactile forms, like Braille.^[4]

Communicating in sign language ^[5]

Origins of Human Language

The earliest origins of human language are hotly contested, as it is hard to find direct evidence for when people first began to speak. It is also likely that there was an intermediate period during which our communication systems were comparable to those of other primates, and even if we did have knowledge of what this was like, it would be hard to say exactly when we crossed over from animal communication to human language.

Proto-Indo-European (PIE) is the name for the common ancestor of the Indo-European language family. A language family is a group of languages descended from a common language. The Indo-European language family contains 445 current languages, and all of them are thought to have descended from PIE.

Not all languages that have ever been spoken are still commonly used. For example, Latin, which was spoken in the Roman Empire, is now considered a dead language, or a language that has no native speakers.^[6]

Theories of Language Development

Psychological theories of language learning differ in terms of the importance they place on nature and nurture. Remember that we are a product of both nature and nurture.  Researchers now believe that language acquisition is partially inborn and partially learned through our interactions with our linguistic environment (Gleitman & Newport, 1995; Stork & Widdowson, 1974). First to be discussed are the biological theories, including nativism, brain areas, and critical periods.  Next, learning theory and social pragmatics will be presented.

Biological Theories of Language

Nativism

The linguist Noam Chomsky is a believer in the nature approach to language, or nativism, arguing that human brains contain a language acquisition device (LAD) that includes a universal grammar that underlies all human language (Chomsky, 1965, 1972). According to this approach, each of the many languages spoken around the world (there are between 6,000 and 8,000) is an individual example of the same underlying set of procedures that are hardwired into human brains. Chomsky’s account proposes that children are born with a knowledge of general rules of syntax that determine how sentences are constructed. Language develops as long as the infant is exposed to it. No teaching, training, or reinforcement is required for language to develop as proposed by Skinner.

Noam Chomsky ^[7]

Chomsky differentiates between the deep structure of an idea; that is, how the idea is represented in the fundamental universal grammar that is common to all languages, and the surface structure of the idea or how it is expressed in any one language. Once we hear or express a thought in surface structure, we generally forget exactly how it happened.  For example, at the end of a lecture, you will remember a lot of the deep structure (i.e., the ideas expressed by the instructor), but you cannot reproduce the surface structure (the exact words that the instructor used to communicate the ideas).

Although there is general agreement among psychologists that babies are genetically programmed to learn language, there is still debate about Chomsky’s idea that there is a universal grammar that can account for all language learning.  Evans and Levinson (2009) surveyed the world’s languages and found that none of the presumed underlying features of the language acquisition device were entirely universal. In their search, they found languages that did not have noun or verb phrases, that did not have tenses (e.g., past, present, future), and even some that did not have nouns or verbs at all, even though a basic assumption of a universal grammar is that all languages should share these features.^[8]

Brain Areas for Language

For the 90% of people who are right-handed, language is stored and controlled by the left cerebral cortex, although for some left-handers this pattern is reversed. These differences can easily be seen in the results of neuroimaging studies that show that listening to and producing language creates greater activity in the left hemisphere than in the right. Broca’s area, an area in front of the left hemisphere near the motor cortex, is responsible for language production. This area was first localized in the 1860s by the French physician  Paul Broca, who studied patients with lesions to various parts of the brain. ^[9] Damage to Broca’s area can result in productive aphasia (also known as Broca’s aphasia), or an inability to speak. Patients with Broca’s can often still understand language, but they cannot speak fluently.^[10]

Wernicke’s area, an area of the brain next to the auditory cortex, is responsible for language comprehension.^[11] Damage to this area results in receptive aphasia (also called Wernicke’s aphasia). This type of aphasia manifests itself as a loss of comprehension, so sometimes while the patient can apparently still speak, their language is nonsensical and incomprehensible. ^[12]

The primary auditory cortex, located in the temporal lobe and connected to the system, is organized so that it responds to neighboring frequencies in the other cells of the cortex. It is responsible for identifying pitch and loudness of sounds. The angular gyrus, located in the parietal lobe of the brain, is responsible for several language processes, including number processing,  spatial recognition and attention.^[13]

Language areas of the brain  ^[14]

Critical Periods

Psychologists believe there is a critical period, a time in which learning can easily occur, for language. This critical period appears to be between infancy and puberty (Lenneberg, 1967; Penfield & Roberts, 1959), but isolating the exact timeline has been elusive. Children who are not exposed to language early in their lives will likely never grasp the grammatical and communication nuances of language.

Case studies, including Victor the “Wild Child,” who was abandoned as a baby in 18th century France and not discovered until he was 12, and Genie, a child whose parents kept her locked away from 18 months until 13 years of age, are two examples of children who were deprived of language. Both children made some progress in socialization after they were rescued, but neither of them ever developed a working understanding of language (Rymer, 1993).  Yet, such case studies are fraught with many confounds.  How much did the years of social isolation and malnutrition contribute to their problems in language development? A better test for the notion of critical periods for language is found in studies of children with hearing loss. Several studies show that the earlier children are diagnosed with hearing impairment and receive treatment, the better the child’s long-term language development. For instance, Stika et al. (2015)    reported that when children’s hearing loss was identified during newborn screening, and subsequently addressed, the majority showed normal language development when later tested at 12-18 months. Fitzpatrick, Crawford, Ni, and Durieux-Smith (2011) reported that early language intervention in children who were moderately to severely hard of hearing, demonstrated normal outcomes in language proficiency by 4 to 5 years of age. Tomblin et al. (2015) reported that children who were fit with hearing aids by 6 months of age showed good levels of language development by age 2. Those whose hearing was not corrected until after 18 months showed lower language performance, even in the early preschool years. However, this study did reveal that those whose hearing was corrected by toddlerhood had greatly improved language skills by age 6. The research on hearing-impaired children reveals that this critical period for language development is not exclusive to infancy and that the brain is still receptive to language development in early childhood. Fortunately, it has become routine to screen hearing in newborns, because when hearing loss is not treated early, it can delay spoken language, and literacy, and impact children’s social skills (Moeller & Tomblin, 2015).

Learning Theory

Perhaps the most straightforward explanation of language development is that it occurs through the principles of learning, including association and reinforcement (Skinner, 1953). Additionally, Bandura (1977) described the importance of observation and imitation of others in learning language. There must be at least some truth to the idea that language is learned through environmental interactions or nurture. Children learn the language that they hear spoken around them rather than some other language. Also supporting this idea is the gradual improvement of language skills with time. It seems that children modify their language through imitation and reinforcement, such as parental praise and being understood. For example, when a two-year-old child asks for juice, he might say, “me juice,” to which his mother might respond by giving him a cup of apple juice.

However, some contend that language cannot be entirely learned. For one, children learn words too fast for them to be learned through reinforcement. Between the ages of 18 months and 5 years, children learn up to 10 new words every day (Anglin, 1993).  However, the results of generalized imitation research (e.g., Poulson et al, 1991) indicate that only some words need to be reinforced.  Words that were not reinforced still increased in their frequency.  ^[15].

Other evidence that refutes the idea that all language is learned comes from the observation that children may learn languages better than they ever hear them.  Deaf children whose parents do not communicate using ASL very well nevertheless are able to learn it perfectly on their own and may even make up their own language if they need to (Goldin-Meadow & Mylander, 1998).  A group of deaf children in a school in Nicaragua, whose teachers could not sign, invented a way to communicate through made-up signs       (Senghas, Senghas, & Pyers, 2005). The development of this new Nicaraguan Sign Language has continued and changed as new generations of students have come to the school and started using the language. Although the original system was not a real language, it is becoming closer and closer every year, showing the development of a new language in modern times.

Social Pragmatics

Another view, pragmatics, emphasizes the very social nature of human language. Language from this view is not only a cognitive skill but also a social one.  A language is a tool humans use to communicate, connect to, influence, and inform others. Most of all, language comes out of a need to cooperate. The social nature of language has been demonstrated by a number of studies that have shown that children use several pre-linguistic skills (such as pointing and other gestures) to communicate not only their own needs but what others may need.  So, a child watching her mother search for an object may point to the object to help her mother find it. Eighteen-month to 30-month-olds have been shown to make linguistic repairs when it is clear that another person does not understand them (Grosse, Behne, Carpenter & Tomasello, 2010). Grosse et al. (2010) found that even when the child was given the desired object if there had been any misunderstanding along the way (such as a delay in being handed the object, or the experimenter calling the object by the wrong name), children would make linguistic repairs. This would suggest that children are using language not only as a means of achieving some material goal, but to make themselves understood in the mind of another person.^[16]

Language is not only a cognitive skill but also a social one. ^[17]

Statistical Learning

Research in the last two decades has revealed powerful statistical learning abilities in infants, including the developing capacity to cull statistical regularities from a variety of auditory inputs ( words) including artificial and natural language (e.g., Saffran et al., 1996a; Saffran et al., 1996b; Pelucchi et al., 2009).  Given the richness and complexity of a language, how is it that infants acquire vocabulary and structure so rapidly, and seemingly effortlessly, in their first years after birth?  For example, one challenge facing young language learners is the fact that speakers do not mark word boundaries with pauses, and infants must rely on other information to accomplish this task.

Researchers hypothesized that the statistical structure of a language might be important for word division (Harris, 1955; Hayes and Clark, 1970). Saffran et al. (1996a,b) proposed a mechanism for statistical word segmentation: transitional probability (TP) detection. In their experiments, adults, first-graders, and 8-month-olds were presented with a continuous stream of speech from an artificial language in which word boundaries were indicated by differing TPs between syllables within words (high TPs) and across words (low TPs).  After brief exposure to this language, listeners in all three age groups were able to distinguish between high TP syllable sequences (“words”) and low TP sequences (“part-words”). Thus, both infant and adult learners appeared sensitive to the TP information contained in the speech stream, suggesting that statistical learning via sensitivity to TPs is a possible mechanism contributing to language acquisition. ^[18]

Language and Cognition

It is easy to wonder which comes first, the thought or the language. Does an individual first think of an idea or did speaking, hearing, or reading about an idea spur a thought? Can thought exist without language? You might as well ask which came first, the chicken or the egg.   Language and thought (or “cognition”) tend to interact in a dual and cyclical relationship, a theory known overall as linguistic relativity. What one thinks becomes what one communicates, and what one communicates can lead to new thoughts. There are several different theories that aim to discuss the relationship between cognition and language, and each will be discussed in this chapter.

Piaget’s Theory

Jean Piaget’s theory of language development suggests that children use both assimilation and accommodation to learn language. Assimilation is the process of changing one’s environment to place information into an already-existing schema (or idea). Accommodation is the process of changing one’s schema to adapt to the new environment. Piaget believed children need to first develop cognitively before language acquisition can occur. According to him, children first create mental structures within the mind   (schemas) and from these schemas, language development happens.

Vygotsky’s theory

Lev Vygotsky’s theory of language development focused on social learning and the zone of proximal development (ZPD). The ZPD is a level of development obtained when children engage in social interactions with others; it is the distance between a child’s potential to learn and the actual learning that takes place. Vygotsky’s theory also demonstrated that Piaget underestimated the importance of social interactions in the development of language.^[19]

The Sapir-Whorf Hypothesis

The Sapir-Whorf hypothesis states that the grammatical structure of a person’s language influences the way he or she perceives the world. The hypothesis has been largely abandoned by linguists as it has found at best very limited experimental support, and it does not hold much merit in psychology. For instance, studies have not shown that speakers of languages lacking a subjunctive mood (such as Chinese) experience difficulty with hypothetical problems. The weaker version of this theory does have some merit, however. For example, different words mean different things in different languages; not every word in every language has a one-to-one exact translation in a different language.  Because of these small but important differences, using the wrong word within a particular language (because you believe it to mean something else) can have dire consequences.

An example of studying linguistic relativity is in the area of color naming. Sapir and Whorf, as believers in linguistic relativity, would believe that people whose languages partition the color spectrum along different lines actually perceive colors in a different way. However, recent research has supported the idea that human color perception is governed more by biological and physical rather than linguistic constraints, regardless of how many color words a language has.

Cognitive-Behavioral Therapy

According to the theory that drives cognitive-behavioral therapy, the way a person thinks has a huge impact on what she or he says and does. Founded by Aaron T. Beck, this school of thought discusses the interplay among emotion, behavior, language, and thought. Since internal dialogue is a form of language, the way we speak to ourselves can influence our daily lives. Problems with our internal dialogue, known as cognitive distortions, can lead to negative behaviors and serious emotional problems.

Components of Language

Phonemes and Phonology

A phoneme is the smallest unit of sound that makes a meaningful difference in a language and the study of phonemes is phonology.   The word “bit” has three phonemes. In spoken languages, phonemes are produced by the positions and movements of the vocal tract, including our lips, teeth, tongue, vocal cords, and throat, whereas in sign languages phonemes are defined by the shapes and movement of the hands.

There are hundreds of unique phonemes that can be made by human speakers, but most languages only use a small subset of the possibilities. English contains about 45 phonemes, whereas other languages have as few as 15 and others more than 60. The Hawaiian language contains fewer phonemes as it includes only 5 vowels (a, e, i, o, and u) and 7 consonants (h, k, l, m, n, p, and w).

Infants are born able to detect all phonemes, but they lose their ability to do so as they get older; by 10 months of age, a child’s ability to recognize phonemes becomes very similar to that of the adult speakers of the native language. Phonemes that were initially differentiated come to be treated as equivalent (Werker & Tees, 2002).

Morphemes and Morphology

Morphology is the study of words and other meaningful units of languages like suffixes and prefixes. ^[20] Whereas phonemes are the smallest units of sound in language, a morpheme is a string of one or more phonemes that makes up the smallest units of meaning in a language.  Some morphemes are prefixes and suffixes used to modify other words. For  example, the syllable “re-” as in “rewrite” or “repay” means “to do again,” and the suffix “-est” as in “happiest” or “coolest” means “to the maximum.” ^[21]

Syntax

Syntax is the study of sentences and phrases, or how people put words into the right order so that they can communicate meaningfully. All languages have underlying rules of syntax, which, along with morphological rules, make up every language’s grammar. An example of syntax coming into play in language is “Eugene walked the dog” versus “The dog walked Eugene.”  The order of words is not arbitrary—in order for the sentence to convey the intended meaning, the words must be in a certain order.

Semantics

Semantics, most generally, is about the meaning of sentences.  Someone who studies semantics is interested in words and what real-world object or concept those words denote, or point to.^[22]

 Pragmatics

The social side of language is expressed through pragmatics, or how we communicate effectively and appropriately with others. Examples of pragmatics include turn-taking, staying on topic, volume and tone of voice, and appropriate eye contact.

Lastly, words do not possess fixed meanings but change their interpretation as a function of the context in which they are spoken.  We use contextual information, the information surrounding language, to help us interpret it.  Examples of contextual information include our knowledge and nonverbal expressions, such as facial expressions, postures, and gestures.  Misunderstandings can easily arise if people are not attentive to contextual information or if some of it is missing, such as it may be in newspaper headlines or in text messages. ^[23]

Levels of Linguistic Structure  ^[24]

The Developmental Progression of Language

Infancy and Toddlerhood

Do newborns communicate? Of course, they do. They do not, however, communicate with the use of oral language. Instead, they communicate their thoughts and needs with body posture (being relaxed or still), gestures, cries, and facial expressions. A person who spends adequate time with an infant can learn which cries indicate pain and which ones indicate hunger, discomfort, or frustration.

 In terms of producing spoken language, babies begin to coo almost immediately. Cooing is a one-syllable combination of a consonant and a vowel sound (e.g., coo or ba). Interestingly, babies replicate sounds from their own languages. A baby whose parents speak French will coo in a different tone than a baby whose parents speak Spanish or Urdu. These gurgling, musical vocalizations can serve as a source of entertainment to an infant who has been laid down for a nap or seated in a carrier on a car ride. Cooing serves as practice for vocalization, as well as the infant hears the sound of his or her own voice and tries to repeat sounds that are entertaining. Infants also begin to learn the pace and pause of conversation as they alternate their vocalization with that of someone else and then take their turn again when the other person’s vocalization has stopped.

At about four to six months of age, infants begin making even more elaborate vocalizations that include the sounds required for any language. Guttural sounds, clicks, consonants, and vowel sounds stand ready to equip the child with the ability to repeat whatever sounds are characteristic of the language heard. Eventually, these sounds will no longer be used as the infant grows more accustomed to a particular language.

At about 7 months, infants begin babbling, engaging in intentional vocalizations that lack specific meaning and comprise a consonant-vowel repeated sequence, such as ma-ma-ma, da-da-da. Children babble as practice in creating specific sounds, and by the time they are a  year old, the babbling uses primarily the sounds of the language that they are learning (de Boysson-Bardies, Sagart, & Durand, 1984). These vocalizations have a conversational tone that sounds meaningful even though it is not. Babbling also helps children understand the social, and communicative functions of language. Children who are exposed to sign language babble in sign by making hand movements that represent real language (Petitto & Marentette, 1991).

Children communicate information through gesturing long before they speak, and there is some evidence that gesture usage predicts subsequent language development (Iverson & Goldin-Meadow, 2005). Deaf babies also use gestures to communicate wants, reactions, and feelings. Because gesturing seems to be easier than vocalization for some toddlers, sign language is sometimes taught to enhance one’s ability to communicate by making use of the ease of gesturing. The rhythm and pattern of language is used when deaf babies sign, just as it is when hearing babies babble.

At around ten months of age, the infant can understand more than he or she can say, which is referred to as receptive language. You may have experienced this phenomenon as well if you have ever tried to learn a second language. You may have been able to follow a conversation more easily than contribute to it. One of the first words that children understand is their own name, usually by about 6 months, followed by commonly used words like “bottle,” “mama,” and “doggie” by 10 to 12 months (Mandel, Jusczyk, & Pisoni, 1995). Infants shake their head “no” around 6–9 months, and they respond to verbal requests to do things like “wave bye-bye” or “blow a kiss” around 9–12 months. Children also use contextual information, particularly the cues that parents provide, to help them learn language. Children learn that people are usually referring to things that they are looking at when they are speaking (Baldwin, 1993), and that the speaker’s emotional expressions are related to the content of their speech.

Children begin using their first words at about 12 or 13 months of age and may use partial words to convey thoughts at even younger ages. These one-word expressions are referred to as holophrastic speech. For example, the child may say “ju” for the word “juice” and use this sound when referring to a bottle. The listener must interpret the meaning of the holophrase, and when this is someone who has spent time with the child, interpretation is not too difficult. But, someone who has not been around the child will have trouble knowing what is meant. Imagine the parent who to a friend exclaims, “Ezra’s talking all the time now!” The friend hears only “ju da ga” to which the parent explains means, “I want some milk when I go with Daddy.”

The early utterances of children contain many errors, for instance, confusing /b/ and /d/, or /c/ and /z/. The words children create are often simplified, in part because they are not yet able to make the more complex sounds of the real language (Dobrich & Scarborough, 1992). Children may say “keekee” for kitty, “nana” for banana, and “vesketti” for spaghetti because it is easier. Often these early words are accompanied by gestures that may also be easier to produce than the words themselves. Children’s pronunciations become increasingly accurate between 1 and 3 years, but some problems may persist until school age.

A child who learns that a word stands for an object may initially think that the word can be used for only that particular object, which is referred to as underextension. Only the family’s Irish Setter is a “doggie”, for example. More often, however, a child may think that a label applies to all objects that are similar to the original object, which is called overextension. For example, all animals become “doggies”. The first error is often the result of children learning the meaning of a word in a specific context, while the second language error is a function of the child’s smaller vocabulary.

If the child is using English, the first words tend to be nouns. The child labels objects such as cup, ball, or other items that they regularly interact with. In a verb-friendly language such as Chinese, however, children may learn more verbs. This may also be due to the different emphasis given to objects based on culture. Chinese children may be taught to notice action and relationships between objects, while children from the United States may be taught to name an object and its qualities (color, texture, size, etc.). These differences can be seen when comparing interpretations of art by older students from China and the United States (Imai et al., 2008).

By the time they become toddlers, children have a vocabulary of about 50-200 words and begin putting those words together in telegraphic speech, such as “baby bye-bye” or “doggie pretty”. Words needed to convey messages are used, but the articles and other parts of speech necessary for grammatical correctness are not yet used. These expressions sound like a telegraph, or perhaps a better analogy today would be that they read like a text message. Telegraphic speech, or text message speech, occurs when unnecessary words are not used. “Give baby ball” is used rather than “Give the baby the ball.”

Why is a horse a “horsie”? Have you ever wondered why adults tend to use “baby talk” or that sing-song type of intonation and exaggeration used when talking to children? This represents a universal tendency and is known as infant-directed speech.

Infants are more attuned to the tone of voice than to the content of words themselves. ^[25]

It involves exaggerating the vowel and consonant sounds, using a high-pitched voice, and delivering the phrase with great facial expression (Clark, 2009). Why is this done? Infants are frequently more attuned to the tone of voice of the person speaking than to the content of the words themselves and are aware of the target of speech. Werker, Pegg, and McLeod (1994) found that infants listened longer to a woman who was speaking to a baby than to a woman who was speaking to another adult. Adults may use this form of speech in order to clearly articulate the sounds of a word so that the child can hear the sounds involved. It may also be because when this type of speech is used, the infant pays more attention to the speaker and this sets up a pattern of interaction in which the speaker and listener are in tune with one another.^[26]

Early Childhood

Vocabulary Growth

In a classic paper, Carey (1978) made reference to young children’s “word-learning wizardry.” children learn 9 new words a day, every day, from about 18 months of age until about 6 years of age (when estimates suggest they will have amassed a vocabulary of roughly 14,000 words). This astounding feat has captured the imagination of researchers around the world, and countless studies have examined children’s amazing ability to learn a large number of words within a relatively brief developmental period.

Carey (1978) estimated that a young child is working out the meanings of roughly 1,600 words at any given point in time. If we assume that it takes about 6 months to map out the full meaning of a word, then in order to get to that magic number of 14,000 words by age 6, children must have over 1,600 words under construction at a time. The full conceptual representation of a word may take months (perhaps years) to develop because each word is initially mapped onto only a partial understanding – that is, a placeholder.  By “placeholder”, we refer to a special kind of partial meaning that can change, or become elaborated with, increasing knowledge.

The initial process of establishing some sort of placeholder meaning for a word is termed fast-mapping; the more extended and challenging task of figuring out the rest of that representation is termed extended-mapping. Carey and Bartlett’s (1978) classic “chromium” study provides an illustration of how fast-mapping falls short of extended-mapping. In their study, 3-year-olds learned a new word (“chromium”) in the context of an object that was olive-green in color. One week after a single experience with the word, the participants displayed some recall of the word, some understanding of the concept (e.g., grasping that olive-green differs from forest green, even if originally they had merged the two into a single, undifferentiated “green” category), and some knowledge of the word’s meaning (e.g., that it refers to a color). Importantly, however, these understandings were all incomplete. Children’s recall of the word was partial at best (e.g., “crum” instead of chromium); their understanding of the concept (e.g., how olive-green relates to other colors) was improved relative to baseline (before exposure to the word) but far from perfect; and their knowledge of the word’s meaning was imprecise (e.g., knowing that olive-green had a name, but not which name, or knowing that “chromium” referred to a color, but not which color). As these data suggest, fast-mapping is quick– but it is incomplete, and the resulting mapping is best construed as a placeholder, yet it is the partial nature of early meanings is that permits the rapid early learning of words.^[27]

The parts of speech that are learned depend on the language and what is emphasized. Children speaking verb-friendly languages such as Chinese and Japanese, tend to learn nouns more readily. But, those learning less verb-friendly languages such as English, seem to need assistance in grammar to master the use of verbs (Imai, et al, 2008).^[28]

The use of constraints is another mechanism for increasing vocabulary.  Word learning constraints are assumptions or biases that allow children to quickly rule out alternative meanings when learning a new word. They begin to manifest themselves around 18 months when children begin to rapidly expand their vocabulary. These biases are important for children with limited processing abilities if they are to be successful in word learning. These biases include the whole object assumption––the assumption that a word labels a whole object rather than part of an object; the shape bias––the bias to generalize a word to other objects with the same shape; the taxonomic assumption, or noun-category bias, under which a word is hypothesized to extend to other members of the same category (e.g., “dog” refers to the family dog and the neighbor’s dog, rather than the family dog and thematically-related objects like bones); and mutual exclusivity, under which children assign a new word to an object and then assume there can only be one label for it. ^[29]

In addition to fast mapping and constraints, children will use other mechanisms called syntactic bootstrapping and semantic bootstrapping. Syntactic bootstrapping occurs when children use their knowledge of syntax to help them figure out what words mean. If a child hears an adult point to a strange object and say, “this is a dirb,” they will infer that a “dirb” is a thing, but if they hear them say, “this is one of those dirb things” they will infer that it refers to the color or other characteristic of the object. And if they hear the word “dirbing,” they will infer that “dirbing” is something that we do (Waxman, 1990). Waxman, S. R. (1990). ^[30]  Research by Latisha Naigles (1990) concluded that toddlers are sensitive to syntactic cues. She presented two-year-olds with a video of two animals where a rabbit was doing something (i.e., an action) to a duck and a duck was doing something (i.e., an action) to a rabbit. One group received the sentence “The rabbit is gorping the duck” while the other received the sentence “The rabbit and the duck are gorping”. When told to find gorping in two other pictures, they could correctly identify it given the syntactic form they were given (whether it was transitive or not).^[31]  Semantic bootstrapping refers to the hypothesis that children utilize their conceptual knowledge to create grammatical categories. Thus, for example, concepts like “type of object/person” map directly onto the linguistic category “noun” or concepts like “action” map onto the linguistic category “verb”, etc. This will get children started on their way to acquiring parts of speech, which later can be supplemented by other linguistic information. The hypothesis received some support from the experiments that showed that three- to five-year-olds do, in fact, generally use nouns for things and verbs for actions more often than adults do. However, syntactic bootstrapping and learning from distributional patterns of the language have also been proposed as a way for children to acquire word classes.^[32]

Literal Meanings

Children can repeat words and phrases after having heard them only once or twice. But they do not always understand the meaning of the words or phrases. This is especially true of expressions or figures of speech that are taken literally. For example, two preschool-aged girls began to laugh loudly while listening to a tape-recording of Disney’s “Sleeping Beauty” when the narrator reports, “Prince Phillip lost his head!” They imagine his head popping off and rolling down the hill as he runs and searches for it. Or a classroom full of preschoolers hears the teacher say, “Wow! That was a piece of cake!” The children began asking “Cake? Where is my cake? I want cake!”

Overregularization

Children learn rules of grammar as they learn language but may apply these rules inappropriately at first. For instance, a child learns to add “ed” to the end of a word to indicate past tense. Then form a sentence such as “I goed there. I doed that.” This is typical at ages 2 and 3. They will soon learn new words such as “went” and “did” to be used in those situations.

The Impact of Training

Remember Vygotsky and the zone of proximal development? Children can be assisted in learning language by others who listen attentively, model more accurate pronunciations and encourage elaboration. The child exclaims, “I goed there!” and the adult responds, “You went there? Say, ‘I went there.’ Where did you go?” Children may be ripe for language as Chomsky suggests, but active participation in helping them learn is important for language development as well. The process of scaffolding is one in which the adult (or more skilled peer) provides needed assistance to the child as a new skill is learned.

Language Development in Middle Childhood

Vocabulary

One of the reasons that children can classify objects in so many ways is that they have acquired a vocabulary to do so. By fifth grade, a child’s vocabulary has grown to 40,000 words.  It grows at a rate that exceeds that of those in early childhood. This language explosion, however, differs from that of younger children because it is facilitated by being able to associate new words with those already known, and because it is accompanied by a more sophisticated understanding of the meanings of a word.

New Understanding

Those in middle and late childhood are also able to think of objects in less literal ways. For example, if asked for the first word that comes to mind when one hears the word “pizza”, the younger child is likely to say “eat” or some word that describes what is done with a pizza. However, the older child is more likely to place pizza in the appropriate category and say “food”. This sophistication of vocabulary is also evidenced by the fact that older children tell jokes and delight in doing so. They may use jokes that involve plays on words such as “knock-knock” jokes or jokes with punch lines. Young children do not understand play on words and tell “jokes” that are literal or slapstick, such as “A man fell down in the mud! Isn’t that funny?”^[33]

Grammar

Because all language obeys a set of combinatory rules, we can communicate an infinite number of concepts. While every language has a different set of rules, all languages do obey rules. These rules are known as grammar. Speakers of a language have internalized the rules and exceptions for that language’s grammar. There are rules for every level of language—word formation (for example, native speakers of English have internalized the general rule that -ed is the ending for past-tense verbs, so even when they encounter a   brand-new verb, they automatically know how to put it into past tense); phrase formation (for example, knowing that when you use the verb “buy,” it needs a subject and an object; “She buys” is wrong, but “She buys a gift” is okay); and sentence formation.

Older children are also able to learn new rules of grammar with more flexibility.  While younger children are likely to be reluctant to give up saying “I goed there”, older children will learn this rather quickly along with other rules of grammar.

Context  

Words do not possess fixed meanings but change their interpretation as a function of the context in which they are spoken. We use contextual information—the information surrounding language—to help us interpret it.  Context is how everything within language works together to convey a particular meaning. Context includes tone of voice, body language, and the words being used. Depending on how a person says something, holds his or her body or emphasizes certain points of a sentence, a variety of different messages can be conveyed. For example, the word “awesome,” when said with a big smile, means the person is excited about a situation. “Awesome,” said with crossed arms, rolled eyes, and a sarcastic tone which means the person is not thrilled with the situation.^[34]

Metalinguistic Awareness

Metalinguistic awareness is defined as the awareness and or understanding of the rules used to govern language. Patrick Hartwell points out how substantial it is for students to develop these capabilities, especially heightened phonological awareness:  the detection and manipulation of sounds which is a key precursor to literacy. Research by Elizabeth McAllister (1989) has concluded that metalinguistic abilities are associated with cognitive development and is contingent on metalinguistic awareness- which relates to reading skill level, academic success and cultural environment that starts at infancy and continues through preschool.  Therefore, an essential aspect to language development is focused on children being aware of language and the components of language.  ^[35]

Literacy

Emergent literacy is a term that is used to explain a child’s knowledge of reading and writing skills before they learn how to read and write words. It signals a belief that, in a literate society, young children—even one- and two-year-olds are in the process of becoming literate. Through the support of parents, caregivers, and educators, a child can successfully progress from emergent to conventional reading.

The basic components of emergent literacy include:

• Print motivation: Being interested in and enjoying books.
• Vocabulary: Knowing the names of things.
• Print awareness: Noticing print, knowing how to handle a book, and knowing how to follow words on a page.
• Narrative skills: Being able to describe things and events and to tell stories.
• Letter knowledge: Understanding letters are different from each other, knowing their names and sounds, and recognizing letters everywhere.
• Phonological awareness: Being able to hear and play with the smaller sounds in words.

Emergent literacy is of critical importance in early education in light of research showing that children learn skills that prepare them to read years before they start school.^[36]

Reading

Cognitive developmental research has shown that phonemic awareness—that is, awareness of the component sounds within words—is a crucial skill in learning to read. To measure awareness of the component sounds within words, researchers ask children to decide whether two words rhyme, to decide whether the words start with the same sound, to identify the component sounds within words, and to indicate what would be left if a given sound were removed from a word. Kindergartners’ performance on these tasks is the strongest predictor of reading achievement in third and fourth grade, even stronger than IQ or social class background (Nation, 2008). Moreover, teaching these skills to randomly chosen 4- and 5-year-olds results in their being better readers years later (National Reading Panel, 2000).

A huge milestone in middle childhood is learning to read and write. While the foundations of this were laid in infancy and early childhood, formal instruction on this process usually happens during the school-age years. There isn’t always complete agreement on how children are best taught to read. The following approaches to teaching reading are separated by their methodology, but today, models of reading strive for a balance between the two types of reading methods because they are both recognized as essential for learning to read.

An approach based on phonics teaches reading by making sure children can understand letter-sound correspondences (how letters sound), automatically recognize familiar words, and decode unfamiliar words. This ability to break the code of reading allows children to read words they have never heard spoken before. On the other hand, the whole-language approach attempts to teach reading as naturally as possible. As the sounds of words don’t have meaning, the focus is on reading words and sentences in context (such as real books), rather than learning the sounds and phonemes that make up words.^[37]

Writing

Handwriting is a complex task that involves both visual–motor and cognitive skills (Rosenblum et al., 2010; Bara and Gentaz, 2011). This task is managed in during primary school. Although children begin to integrate visual and proprioceptive information by carrying out the tasks of copying shapes and letters (Daly et al., 2003) when they are preschoolers, it is during the school-age period that they learn to associate movements with the mental image of the letters, and to write from dictation, so becoming able to control the movements proactively (Meulenbroek and Van Galen, 1988). At the same time, practicing that ability during the school period allows the process of handwriting to become more and more automatic (Feder and Majnemer, 2007). The acquisition of handwriting also affects more advanced literacy skills, such as the ability to produce written texts, because children who are in trouble with the graphic design of the graphemes are also likely to have fewer resources for the planning of the text (Berninger et al., 1997).  ^[38]

Handwriting is a complex task that involves both visual–motor and cognitive skills. ^[39]

Bilingualism

Although monolingual speakers often do not realize it, the majority of children around the world are bilingual, meaning that they understand and use two languages (Meyers-Sutton, 2005). Even in the United States, which is a relatively monolingual society, more than 60 million people (21%) speak a language other than English at home (Camarota & Zeigler, 2014; Ryan, 2013). Children who are dual language learners are one of the fastest-growing populations in the United States (Hammer et al., 2014). They make up nearly 30% of children enrolled in early childhood programs, like Head Start. By the time they enter school, they are very heterogeneous in their language and literacy skills, with some children showing delays in being proficient in either one or both languages (Hammer et al., 2014). Hoff (2018) reports language competency is dependent on the quantity, quality, and opportunity to use a language. Dual language learners may hear the same number of words and phrases (quantity) overall, as do monolingual children, but it is split between two languages (Hoff, 2018). Thus, in any single language, they may be exposed to fewer words. They will show higher expressive and receptive skills in the language they come to hear the most.

In addition, the quality of the languages spoken to the child may differ in bilingual versus monolingual families. Place and Hoff (2016) found that for many immigrant children in the United States, most of the English heard was spoken by a non-native speaker of the language. Finally, many children in bilingual households will sometimes avoid using the family’s heritage language in favor of the majority language (DeHouwer, 2007, Hoff, 2018). A common pattern in Spanish-English homes is for the parents to speak to the child in Spanish, but for the child to respond in English. As a result, children may show little difference in receptive skills between English and Spanish, but better expressive skills in English (Hoff, 2018).

There are several studies that have documented the advantages of learning more than one language in childhood for cognitive executive function skills. Bilingual children consistently outperform monolinguals on measures of inhibitory control, such as ignoring irrelevant information (Bialystok, Martin & Viswanathan,   2005). Studies also reveal an advantage for bilingual children on measures of verbal working memory (Kaushanskaya, Gross, & Buac, 2014; Yoo & Kaushanskaya, 2012) and non-verbal working memory (Bialystok, 2011).   However, it has been reported that among lower SES populations the working memory advantage is not always found (Bonifacci, Giombini, Beloocchi, & Conteno, 2011).

There is also considerable research to show that being bilingual, either as a child or an adult, leads to greater efficiency in the word-learning process.  Monolingual children are strongly influenced by the mutual-exclusivity bias, the assumption that an object has only a single name (Kaushanskaya, Gross, & Buac, 2014). For example, a child who has previously learned the word car may be confused when this object is referred to as an automobile or sedan. Research shows that monolingual children find it easier to learn the name of a new object than to acquire a new name for a previously labeled object. In contrast, bilingual children and adults show little difficulty with either task (Kaushanskaya & Marian, 2009). This finding may be explained by the experience bilinguals have in translating between languages when referring to familiar objects.^[40]

Students who are fluent in two languages have a cognitive advantage. ^[41]

Speech and Language Disorders

 Aphasia  

A loss of the ability to produce or understand language is referred to as aphasia. Without the brain, there would be no language. The human brain has a few areas that are specific to language processing and production. When these areas are damaged or injured, capabilities for speaking or understanding can be lost, a disorder known as aphasia. These areas must function together in order for a person to develop, use, and understand language.

Articulation Disorders

An articulation disorder refers to the inability to correctly produce speech sounds (phonemes) because of imprecise placement, timing, pressure, speed, or flow of movement of the lips, tongue, or throat (NIDCD, 2016). Sounds can be substituted, left off, added or changed. These errors may make it hard for people to understand the speaker. They can range from problems with specific sounds, such as lisping to severe impairment in the phonological system. Most children have problems pronouncing words early on while their speech is developing. However, by age three, at least half of what a child says should be understood by a stranger. By age five, a child’s speech should be mostly intelligible. Parents should seek help if by age six the child is still having trouble producing certain sounds. It should be noted that accents are not articulation disorders (Medline Plus, 2016a).

Fluency disorders

Fluency disorders affect the rate of speech. Speech may be labored and slow, or too fast for listeners to follow. The most common fluency disorder is stuttering.   Stuttering is a speech disorder in which sounds, syllables, or words are repeated or last longer than normal. These problems cause a break in the flow of speech, which is called dysfluency (Medline Plus, 2016b). About 5% of young children, aged two-five, will develop some stuttering that may last from several weeks to several years (Medline Plus, 2016c). Approximately 75% of children recover from stuttering. For the remaining 25%, stuttering can persist as a lifelong communication disorder (National Institute on Deafness and other Communication Disorders, NIDCD, 2016). This is called developmental stuttering and is the most common form of stuttering. Brain injury, and in very rare instances, emotional trauma may be other triggers for developing problems with stuttering. In most cases of developmental stuttering, other family members share the same communication disorder. Researchers have recently identified variants in four genes that are more commonly found in those who stutter

Voice Disorders

Voice disorders involve problems with pitch, loudness, and quality of the voice (American Speech-Language and Hearing Association, 2016). It only becomes a disorder when problems with the voice make the child unintelligible. In children, voice disorders are significantly more prevalent in males than in females. Between 1.4% and 6% of children experience problems with the quality of their voice. Causes can be due to structural abnormalities in the vocal cords and/or larynx, functional factors, such as vocal fatigue from overuse, and in rarer cases psychological factors, such as chronic stress and anxiety. ^[42]