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.