What is the critical period hypothesis?

age age and language learning critical period hypothesis elt Oct 22, 2021

By Dr Jeremy Koay

A limited view

The Critical Period Hypothesis claims that an optimal period for language acquisition exists and that this period ends at puberty (Abello-Contesse, 2009). Studies that adhere to this hypothesis typically focus on pronunciation and grammar, as DeKeyser (2000) summarises.

Although it is generally agreed that children are better at learning a language than people past a certain age, opinions of this hypothesis vary. A limited view of the critical period hypothesis holds that the ability to learn a language is determined by learner’s biological age. While this might be partially true, it is important to also consider social, affective, educational and experiential aspects that intersect with age (Abello-Contesse, 2009).

A holistic view

Rather than one critical period, some research has proposed multiple critical periods, each one based on a particular language component. For example, some studies claim that the best age period for learning pronunciation is below six, as Abello-Contesse (2009) reports. Some studies (e.g. Cenoz, 2003) show that older children and teenagers are more efficient learners than younger children, because more mature learners have a higher level of cognitive development (Cenoz, 2003).

However, to claim that learners in one group are better than others, does not, unfortunately, help teachers to support their students more effectively. Nevertheless, an awareness of the relationship between age and language learning can help them have realistic expectations about their learners’ progress.

Theory and practice

A useful principle is that it is never too early or too late to learn a language. The view that adults are less efficient learners may discourage them from putting in more effort to improve their language skills. Similarly, parents who believe that children are too young to learn a language may deprive them of exposure to a new target language.

Rather than thinking of age as the only or most important factor, teachers can think about language needs and learning goals of different age groups. For example, young children learning English as an additional language may focus on basic literacy skills as well as on fun. Some retired people may decide to learn a new language for leisure and this would involve different language development expectations compared to those of pre-university English courses.


Abello-Contese, C. (2009). Age and the critical period hypothesis. ELT Journal, 63(2), 170-172.

Cenoz, J. (2003). The influence of age on the acquisition of English: General proficiency, attitudes and code-mixing. In M. García Mayo, & M. García Lecumberri (Eds.), Age and the acquisition of English as a foreign language (pp. 77–93). Clevedon: Multilingual Matters.

DeKeyser, R.M. (2009). The robustness of critical period effects in second language acquisition. Studies in Second Language Acquisition, 22(4), 499-533.

Dr Jeremy Koay is a New Zealand-based Independent Researcher and a Research & Development Consultant at EduMaxi. He obtained his PhD in Applied Linguistics from Victoria University of Wellington in 2015. His research interests include Discourse Analysis, Genre Analysis and TESOL.

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