The Critical Period Hypothesis for L2 Acquisition: An Unfalsifiable Embarrassment?

This article focuses on the uncertainty surrounding the issue of the Critical Period Hypothesis. It puts forward the case that, with regard to naturalistic situations, the hypothesis has the status of both “not proven” and unfalsified. The article analyzes a number of reasons for this situation, including the effects of multi-competence, which remove any possibility that competence in more than one language can ever be identical to monolingual competence. With regard to the formal instructional setting, it points to many decades of research showing that, as critical period advocates acknowledge, in a normal schooling situation, adolescent beginners in the long run do as well as younger beginners. The article laments the profusion of definitions of what the critical period for language actually is and the generally piecemeal nature of research into this important area. In particular, it calls for a fuller integration of recent neurolinguistic perspectives into discussion of the age factor in second language acquisition research.

The Role of Theory in SLA Empirical Research on the Critical Period Hypothesis

This paper sets out to peruse the role of various theories or more precisely, hypotheses invoked in SLA research by surveying three empirical studies pertaining to the critical period hypothesis in the SLA of phonetics and phonology. In particular, the three studies which will be reviewed in the next section are titled in chronological order as (1) A critical period for learning to pronounce foreign languages? (Flege, 1987); (2) Reexamining the critical period hypothesis: A case study of successful adult SLA in a naturalistic environment. (Ioup et al., 1994); (3) Ultimate attainment in L2 Phonology: The Critical Factors of Age, Motivation, and Instruction (Moyer, 1999).

Investigating the Influences of Starting Age on Pronunciation: a Comparative Study of Chinese Learners of English As a Second Language

This study aims to test the validity of Critical Period Hypothesis (CPH) by investigating the influence of starting age on Chinese English learners’ pronunciation. The study compares the degree of foreign accent of native Chinese English learners with different starting ages in learning English, in an attempt to determine whether early Chinese English learners could outperform late ones in terms of English pronunciation when exposed to an English-speaking setting. Furthermore, this research also proposes to investigate other possible factors that affect Chinese English learners’ pronunciation. Participants were asked to provide spontaneous speech samples through semi-structured interviews conducted face-to-face or via Skype. In addition, an additional read-aloud task was required to ensure a more thorough and in-depth interpretation. The final results run counter to the Critical Period Hypothesis as there appeared to be late starters who also achieved native-like pronunciation, and there was no significant difference between early starters and late ones in terms of pronunciation. However, the study also yielded some results suggesting that greater efforts and stronger motivations were required for late starters in order to achieve the same pronunciation levels as early starters’, indicating that starting age can be a sensitive rather than critical factor for second language (L2) pronunciation acquisition.

Imagination exercises improve language in younger but not in older children with autism suggesting a strong critical period

Imagination exercises administered by caregivers were investigated in a three-year-long observational trial of 3,540 children with autism aged 2-12 years. Tablet-based verbal and nonverbal exercises modeled on language therapy and emphasizing mental-juxtaposition-of-objects were organized into an application called Mental Imagery Therapy for Autism (MITA). MITA-exposed children were matched to the ‘Treatment-as-Usual’ participants (TaU, N=5,222) by age, gender, language, sociability, cognitive awareness, health, and ASD severity at baseline. Both younger (2-5 years-of-age) and older children (5-12 YOA) in MITA and TaU groups improved their symptoms over time, but younger MITA-exposed children showed 2.3-fold improvement in language score at the end of the trial vs. TaU group. There was no difference between MITA and TaU in the older children group, supporting Lenneberg’s critical period hypothesis.

The Reliability of Critical Period Hypothesis

This article is an attempt to examine the reliability of the Critical Period Hypothesis (Note 1) in light of subsequent studies. The high improbability of successful L2 acquisition among adults is the main point of strength that CPH enjoys. However, we have incidents of nativelikeness with individuals that began L2 acquisition years past the critical period (Note 2) in addition to supporting studies that show ultimate attainment among L2 learners is still possible. In this case do we still talk about a reliable hypothesis? This opens us to ponder whether CPH is purely biological or there are other social construct factors at play that help some L2 adult learners to attain nativelikness despite the high unlikelihood of its occurrence.