Psychology Language Intro Structure, Theories of Language Acquisition, Language and Nonhuman Primates
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Introduction
Cognitive psychology concerns both language and thought and has been popular only since the 1950s. Before that, many psychologists believed that the scientific method could not be applied toward study of a process as private as thinking. From ancient Greek times, only philosophers and metaphysicians studied the nature of language and thought. The metaphysician René Descartes, for example, famously argued, “I think, therefore I am.”
Today, thanks to increasingly sophisticated tools for studying brain activity, cognitive psychology is a thriving science. Cognitive psychologists explore such questions as how language affects thought, whether it is possible to create a “thinking” machine, and why humans are motivated to create art.
The Structure of Language
Language is a system of symbols and rules that is used for meaningful communication. A system of communication has to meet certain criteria in order to be considered a language:
- A language uses symbols, which are sounds, gestures, or written characters that represent objects, actions, events, and ideas. Symbols enable people to refer to objects that are in another place or events that occurred at a different time.
- A language is meaningful and therefore can be understood by other users of that language.
- A language is generative, which means that the symbols of a language can be combined to produce an infinite number of messages.
- A language has rules that govern how symbols can be arranged. These rules allow people to understand messages in that language even if they have never encountered those messages before.
The Building Blocks of Language
Language is organized hierarchically, from phonemes to morphemes to phrases and sentences that communicate meaning.
Phonemes
Phonemes are the smallest distinguishable units in a language. In the English language, many consonants, such as t, p, and m, correspond to single phonemes, while other consonants, such as c and g, can correspond to more than one phoneme. Vowels typically correspond to more than one phoneme. For example, o corresponds to different phonemes depending on whether it is pronounced as in bone or woman. Some phonemes correspond to combinations of consonants, such as ch, sh, and th.
Morphemes
Morphemes are the smallest meaningful units in a language. In the English language, only a few single letters, such as I and a, are morphemes. Morphemes are usually whole words or meaningful parts of words, such as prefixes, suffixes, and word stems.
Example: The word “disliked” has three morphemes: “dis,” “lik,” and “ed.”
Syntax
Syntax is a system of rules that governs how words can be meaningfully arranged to form phrases and sentences.
Example: One rule of syntax is that an article such as “the” must come before a noun, not after: “Read the book,” not “Read book the.”
Language Development in Children
Children develop language in a set sequence of stages, although sometimes particular skills develop at slightly different ages:
- Three-month-old infants can distinguish between the phonemes from any language.
- At around six months, infants begin babbling, or producing sounds that resemble many different languages. As time goes on, these sounds begin to resemble more closely the words of the languages the infant hears.
- At about thirteen months, children begin to produce simple single words.
- By about twenty-four months, children begin to combine two or three words to make short sentences. At this stage, their speech is usually telegraphic. Telegraphic speech, like telegrams, contains no articles or prepositions.
- By about age three years, children can usually use tenses and plurals.
- Children’s language abilities continue to grow throughout the school-age years. They become able to recognize ambiguity and sarcasm in language and to use metaphors and puns. These abilities arise from metalinguistic awareness, or the capacity to think about how language is used.
Ambiguous Language
Language may sometimes be used correctly but still have an unclear meaning or multiple meanings. In these cases, language is ambiguous—it can be understood in several ways. Avoid biting dogs is an example of an ambiguous sentence. A person might interpret it as Keep out of the way of biting dogs or Don’t bite dogs.
Theories of Language Acquisition
The nature vs. nurture debate extends to the topic of language acquisition. Today, most researchers acknowledge that both nature and nurture play a role in language acquisition. However, some researchers emphasize the influences of learning on language acquisition, while others emphasize the biological influences.
Receptive Language before Expressive Language
Children’s ability to understand language develops faster than their ability to speak it. Receptive language is the ability to understand language, and expressive language is the ability to use language to communicate. If a mother tells her fifteen-month-old child to put the toy back in the toy chest, he may follow her instructions even though he can’t repeat them himself.
Environmental Influences on Language Acquisition
A major proponent of the idea that language depends largely on environment was the behaviorist B. F. Skinner. He believed that language is acquired through principles of conditioning, including association, imitation, and reinforcement.
According to this view, children learn words by associating sounds with objects, actions, and events. They also learn words and syntax by imitating others. Adults enable children to learn words and syntax by reinforcing correct speech.
Critics of this idea argue that a behaviorist explanation is inadequate. They maintain several arguments:
- Learning cannot account for the rapid rate at which children acquire language.
- There can be an infinite number of sentences in a language. All these sentences cannot be learned by imitation.
- Children make errors, such as overregularizing verbs. For example, a child may say Billy hitted me, incorrectly adding the usual past tense suffix -ed to hit. Errors like these can’t result from imitation, since adults generally use correct verb forms.
- Children acquire language skills even though adults do not consistently correct their syntax.
Neural Networks
Some cognitive neuroscientists have created neural networks, or computer models, that can acquire some aspects of language. These neural networks are not preprogrammed with any rules. Instead, they are exposed to many examples of a language. Using these examples, the neural networks have been able to learn the language’s statistical structure and accurately make the past tense forms of verbs. The developers of these networks speculate that children may acquire language in a similar way, through exposure to multiple examples.
Biological Influences on Language Acquisition
The main proponent of the view that biological influences bring about language development is the well-known linguist Noam Chomsky. Chomsky argues that human brains have a language acquisition device (LAD), an innate mechanism or process that allows children to develop language skills. According to this view, all children are born with a universal grammar, which makes them receptive to the common features of all languages. Because of this hard-wired background in grammar, children easily pick up a language when they are exposed to its particular grammar.
Evidence for an innate human capacity to acquire language skills comes from the following observations:
- The stages of language development occur at about the same ages in most children, even though different children experience very different environments.
- Children’s language development follows a similar pattern across cultures.
- Children generally acquire language skills quickly and effortlessly.
- Deaf children who have not been exposed to a language may make up their own language. These new languages resemble each other in sentence structure, even when they are created in different cultures.
Biology and Environment
Some researchers have proposed theories that emphasize the importance of both nature and nurture in language acquisition. These theorists believe that humans do have an innate capacity for acquiring the rules of language. However, they believe that children develop language skills through interaction with others rather than acquire the knowledge automatically.
Language and Nonhuman Primates
Some researchers have tried to teach apes to use language. Because of the structure of their vocal organs, apes can’t say words, but they can communicate using signs or computers. Using these means, apes can make requests, respond to questions, and follow instructions.
The Case of Washoe the Chimpanzee
Researchers at Central Washington University taught a chimpanzee named Washoe to use American Sign Language (ASL) to communicate. She could sign not only single words but also meaningful combinations of words. She could follow instructions and respond to questions given in ASL. Later, Washoe’s foster child, Loulis, learned signs just by watching Washoe and other chimps that had been trained to use language. Some research even suggested that language-trained chimps may use signs spontaneously to communicate with each other or to talk to themselves, although this behavior is not thoroughly documented.
Skepticism about Ape Language
Critics of the idea that apes can learn and use language have maintained several arguments:
- Apes, unlike people, can be trained to learn only a limited number of words and only with difficulty.
- Apes use signs or computers to get a reward, in the same way that other animals can be taught tricks. But learning tricks is not equivalent to learning language.
- Apes don’t use syntax. For example, they don’t recognize the difference between Me eat apple and Apple eat me.
- Trainers may be reading meanings into signs apes make and unintentionally providing cues that help them to respond correctly to questions.
Clearly, communication in nonhuman animals differs drastically from language in humans. The spontaneity, uniqueness, and reflective content of human language remains unmatched.
Nonprimates Can Communicate
Researchers have taught nonprimate animals, such as parrots, to communicate meaningfully. Parrots that participated in language acquisition studies learned to identify dozens of objects, distinguish colors, and make simple requests in English. One famous example is Alex the African gray parrot, owned by Irene Pepperberg from the University of Arizona. Alex can “speak” hundreds of words, but what makes him more unique is that he appears to do more than just vocalize. Though Pepperberg does not claim that Alex uses “language,” she does believe that when Alex talks, he is expressing his thoughts, not just mimicking.
