Critical Period Hypothesis and Acquisition of Language

This essay discusses the Critical Period Hypothesis and its importance in the development of language in humans. It compares the language acquisition of Genie and the study of American Sign Language to prove the hypothesis true.

Running head: LINGUISTICS
Linguistics
Name of the Student
Name of the University
Author Note

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Critical Period Hypothesis and Acquisition of Language
The process by which the humans acquire the ability to understand and form a sense of a
coherent language structure is known as language acquisition, through this process the human
beings create and use the words to make sentences to communicate with others. Language
acquisition most commonly refers to the acquisition of first language, which deals with the study
of the infants and their acquisition of their respective native language. The acquisition of second
language differs from the first language acquisition, it deals with the children or the adults
learning other languages than native language. There are some theories about the acquisition and
development of language in the humans one of which is the “Critical Period Hypothesis”
theorized by Eric Lenneberg, the hypothesis states that there is a certain critical period in the
development and acquisition of language in human beings and if that age is crossed then the
individual faces certain problems in learning language. This essay will argue the importance of
the “critical age hypothesis” in the development of language in humans.
Genie started learning language when she was almost 14 years old, after she was
discovered it was observed that she had almost no skill in language or proper communication
skills. She did not have control over the organs of speech (Curtiss et al., 1974). After she was
taught by the linguists and the psychologists her language acquisition showed that even after
suffering from tragic isolation for a long period of time and absence of vocabulary or language,
she started showing a bit of progress in phonology, she could pronounce several sound
sequences while imitating them but she did not use spontaneous speech till five months into the
research. She gained quite a bit of vocabulary as well but her grammar did not improve, she
could combine two sentences for example “cat hurt” “dog hurt” as “cat dog hurt” but the there

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was no use of grammar. Her syntactic acquisition, was also much slower than any normal child
(Curtiss et al., 1974).
The language development of Genie was different from that of the normal children in
several aspects. The phonological words were a lot different for Genie than the normal children,
the early two syllable words that she spoke were not “reduplicated” which normal children did
speak. She had no intonation and while the normal children learns nouns at first, Genie learned
all the nouns pronouns and verbs but was not able to put it into coherent sentences. In the
comprehension training she was unable to understand the word order and was also unable to
understand passive sentences. She omitted the verbs, objects and subjects from the sentences.
In case of negative sentences the words she was able to speak was the angry ones. She was able
to say "stop it," "no more," "no," and her stock of negative words were very few (Curtiss et al.,
1974). In case of interrogative sentences when she was asked a question she used to respond by
repeating the last words of the sentence uttered by the speaker, also she was never able to use
any interrogative questions.
The study of ASL or American Sign Language is important to contribute to the study of
Critical Period Hypothesis as the study of sign language with the deaf and dumb children more
evidently proves that the ability of acquiring a language decreases with the increase in age
of an individual (Newport, 1990). The three groups of participants in the Newport study were
the Native, Early and Late Learners. Native learners who already had exposure to the ASL from
their birth, they were raised by their deaf parents and had an idea about the language from a
young age. The second were the Early learners who learned ASL after they were taught by their
peers who were also deaf at the age of 4-6 (Newport, 1990). The third group comprised of Late
learners the first time that they were exposed to ASL was with the help of their deaf peers, they

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were more than 12 years of age at the time they learned the language or during the period when
the tests were conducted (Newport, 1990).
The results of the first ASL study suggests that a wide range of studies shows that
acquisition of language occurs successfully in the learners after they have overcome certain
primary problems (Ron, 2015). The purpose of these experiments were to find out how the
language acquisition was affected with the increase of age in the subjects and after the tests were
complete it was found that the children who were taught the language at the age of 12 had a lot
less improvement in the development of the language, while the children who had early exposure
to ASL they showed far better response to the experiments. In case of syntactical and
morphological competence an experiment was conducted on the subjects, they had to listen to a
recording consisting 276 short and simple sentences and they were asked whether the sentences
were correct or not (Newport, 1990). The test score showed that the children who had early
exposure to the language were more able in determining which of the sentences were correct and
which were wrong, thus proving that the effects of “age of acquisition are effects of the
maturational state of the learner” (Granena, 2016).
In the process of comparing both the case studies, the experiments conducted on Genie
and the experiments conducted on the deaf children and ASL study proves that the claims made
in the Critical Period Hypothesis are true (Mayberry & Kluender, 2017). In case of Genie it
was seen that although she made some progress in certain aspects of language acquisition yet she
had various problems related to phonology, grammar acquisition and in forming interrogative
sentence (Choubsaz & Gheitury, 2017). Although she made progress the researchers were unable
to comment on the extent of improvement of language acquisition process in the future. In the
ASL experiments the results were almost similar, the children who had been exposed to the

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language in their early age they were able top the experiment results (Diaz, 2016). Both of the
studies prove that to acquire a proper form of language the individuals are required to be exposed
to their respective native languages from an early age (Strid, 2017).
To conclude, it can be said that the “critical period hypothesis” which says that from
childhood throughout adolescence, this period of time is perfect and most suitable for the
acquisition of first and even second language acquisition. The external and inter factors prevent
the adults to acquire a new language at that age. Judging from both the experiments this
statement can be said to be true that “Critical Period Hypothesis” holds paramount importance in
the development of language in human beings.

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Reference list:
Choubsaz, Y., & Gheitury, A. (2017). Is semantics affected by missing a critical period?
Evidence from the Persian deaf. Journal of psycholinguistic research, 46(1), 77-88.
Curtiss, S., Fromkin, V., Krashen, S., Rigler, D., & Rigler, M. (1974). The linguistic
development of Genie. Language, 528-554.
Diaz, C. (2016). The critical period hypothesis.
Granena, G. (2016). Part 1: Age Differences, Maturational Constraints, and Implicit and Explicit
L2 Learning. Major Research Issues in SLA, 9.
Mayberry, R. I., & Kluender, R. (2017). Rethinking the critical period for language: New
insights into an old question from American Sign Language. Bilingualism: Language and
Cognition, 1-20.
Newport, E. L. (1990). Maturational constraints on language learning. Cognitive science, 14(1),
11-28.
Ron, C. (2015). Relationship between the Phonetic Aspect of Second Language Acquisition and
Age: Testing on the Critical Period Hypothesis in a Selected Function of Language. The
annals of Gifu Shotoku Gakuen University. Faculty of Foreign Languages, 54, 15-28.
Strid, J. E. (2017). The Myth of the Critical Period. TESOL Journal, 8(3), 700-715.