Researchers have sought to determine the origins and mechanisms of child language learning for centuries. Research dates back to the fifth century BC, and the tale of an Egyptian king, Psammetichus I, who devised an experiment meant to determine the world’s first language. His methods included sending two infants into isolation, with only a shepherd to care for their needs and no one to talk to them. The king hoped their first words would offer some clue as to the most ancient tongue, and thus, the most ancient people. He was disappointed when their shared first word was Phrygian, an ancient language of Central Asia Minor, rather than Egyptian. The word they spoke was bekos, Phrygian for bread (Johnson et al. 2000).

Studies within the last several hundred years suggest that Psammetichus I’s infants were not wholly deprived of auditory language influences. Had they been, they would not have acquired any recognizable language, as has been the case for so many “feral,” or “wild,” children. Feral children, those supposedly raised by wild animals with little human involvement and, consequently, with no early language exposure, have been a curiosity to scholars for centuries. A classic example of a feral child is Victor of Averyron, France. In 1799, he was discovered alone in the wilderness by a group of hunters and, upon arriving in civilization, he was placed in the care of a physician. This physician, Jean-Marc Itard, studied Victor for years. Victor was approximately 11 years old when he was discovered in the wild, and had no apparent knowledge of language. Itard studied Victor and attempted, unsuccessfully, to teach him to linguistically verbalize; though the boy learned to communicate via signing, he never learned to speak (Bickerton 1990).

Itard and Victor. Courtesy of Universität Potsdam.

In 1967, Lenneberg used studies of feral children as evidence for the existence of a “critical period” in child language acquisition. According to the critical theory hypothesis, infants have an innate capacity for learning any language; however, if they are not exposed to one in early childhood, they will not acquire language even if later brought into a speaking community. In the wild boy of Aveyron’s case, this proved true. However, one problem with using studies of wild children as evidence for the existence of a critical period is that the original mental capacity of the subjects cannot be easily determined (Johnson et al. 2000). In historical cases, there was no way of determining whether a child could not develop linguistic abilities because of cognitive limitations or illness, or if he had really never been exposed to language.

During the first half of the 20th century, Educators and psychologists conducted broad behaviorist studies on child language development. Smith (1926) used pictures, objects, and questions to discover the productive linguistic ability of children of different ages. He found the following results:

Templin (1957) concluded that six year olds comprehended about 8000 words – well over 5000 more than Smith’s six year olds were able to produce. This demonstrates the fact that vocabulary comprehension always exceeds vocabulary production. The above studies focused on what children could do linguistically – not on how they did it. Behaviorist educators and psychologists in the first half of the 20th century assumed that children learned language from environmental experiences.

B.F. Skinner. Courtesy of www.pbs.org.

In 1957, B. F. Skinner proposed an extreme behaviorist theory for child language acquition in his book Verbal Behavior. Skinner proposed that language develops primarily in response to external reinforcement and that infants and children learn by focusing on “reward contingencies.”

Chomsky. Courtesy of www.copi.com/links2.htm.

Noam Chomsky’s (1957) response to Skinner’s theory inspired a language theory revolution. Chomsky argued that infants are born with a “language faculty,” complete with innate constraints on the forms human language can take and a “universal grammar.” Chomsky established a nativist, as opposed to behaviorist, school of thought. Nativists believe that language is an innate, biologically determined capacity.

1. Localization in cognitive function: Brain lesions can result in specific language impairments while other cognitive abilities remain normal and vice versa (Anderson and Lightfoot 1999).

2. Any child exposed, even in a limited way, to some language triggering experience develops a full capacity for learning language (Anderson and Lightfoot 1999).

3. A child reacts to evidence extracted from the environment in accordance with specific principles, suggesting that the structure for learning language is already present, but the trigger is necessary (Anderson and Lightfoot 1999).
Chomsky

1. The interactive approach, which stresses language-learning and interacting with speakers as vital to developing communicative skills (Vygotsky 1962).

2. The cognitive approach, which posits that language learning is a part of the overall cognitive development of a child (Piaget 1952).

3. The autonomous approach, which emphasizes the independence of language from other cognitive capacities (Fodor 1983).

“Babbles” are vocalization with sounds found in spoken language that have repeated syallables, and lack obvious meaning or reference. Babies usually begin babbling around 6 months, and at least by 10 months. Petitio and Holowka (2002) used a mouth laterality index to measure the degree of right asymmetry during infant vocalizations. This index is based on the fact that, during linguistically related phonations, the right side of the mouth opens further than the left because the left hemisphere of the brain controls both language and the right side of the face. The researchers found that babies’ mouths opened wider on the right side during babbles, on the left side during smiles, and were symmetrical during non-babbles. They concluded that the language control center of the brain was active only during babbling. This supports the argument that linguistic centers in the brain are active early, and that babbling is a linguistic activity.

In early stages of communicative development, spoken languages and gestures usually emerge concurrently (Caselli 1990). So do gestures and first words.

Children initially add both gestures and works to their efforts to communicate (Iverson et al. 1994).

Acheivements in gesturing are a predictor of progress in verbal language abilities (Camaioni et al. 1991).

The onset of pointing is a reliable predictor of the appearance of first words (Bates et al. 1979).

The emergence of gesture-word combinations that convey two distinct pieces of information often predict the emergence of two word speech (Butcher and Goldin-Meadow 2000).

If an infant is linguistically delayed, but has achieved a level of feats in gesturing, the delay is not likely to be permanent (Thal and Tobias 1992).

Bates. E., L. Benigni, I. Bretherton, and V. Volterra. 1979. The Emergence of Symbolic Cognition and Communication in infancy. New York: Academic Press.

Bickerton, D. 1990. Language and Species. Chicago: The University of Chicago Press.

Butcher, C. and M.S. Goldin-Meadow. 2000. Gesture and the transition from one to two word speech: When hand and mouth come together. Pages 235-257 in D. McNeil, editor. Language and Gesture. Cambridge: Cambridge University Press.

Camaioni, L., M.C. Casselli, and E. Longobardi. 1991. A parent report instrument for early assessment. First Language 11:345-359.

Chomsky, N. 1957. Syntactic structures. The Hague: Mouton Press.

Fodor, J.A. 1983. The modularity of the mind. Cambridge: MIT Press.

Holowka, S. and L.A. Petitto. 2002. Left Hemisphere Cerebral Specialization for Babies While Babbling. Science: 297:1515.

Iverson, J.M., O. Capirci, and M.C. Caselli. 1994. From communication to language in two modalities. Cognitive Development 9:23-43.

Lenneberg, E. H. 1967. The biological foundations of language. New York: Wiley.

Piaget, J. 1952. The origins of intelligence in children. New York: International Universalities Press.

Skinner, B.F. 1957. Verbal behavior. Englewood Cliffs: Prentice-Hall.

Smith, N. 1973. The acquisiton of phonology. Cambridge: University Press.

Created by Katherine St. Clair, Biology Senior Seminar
Last updated December 14, 2004