Within both first and
second language acquisition research, a critical or sensitive period for complete attainment has
largely been substantiated in phonological studies, although it is questionable whether age should
be examined in isolation from sociopsychological influences and the extent of exposure to the
second language. This study sets out to challenge the Critical Period Hypothesis (CPH) by
examining phonological performance among highly motivated subjects who use German daily as
graduate student instructors and who have been immersed in the language through in-country
residence, augmented by years of instruction in both language- and content-based courses. The
methodology developed seeks to expand the realm of factors that are potentially conflated with
age, such as instruction, motivation, suprasegmental training, and self-perception of productive
accuracy, and other factors that have not been addressed in previous studies on ultimate
attainment. Production tasks target sounds difficult for nonnative speakers (NNSs) according to
contrastive analysis, and task types range in complexity from isolated words to sentences,
paragraphs, and free speech. A mean rating was computed for each speaker, including native
speaker controls, according to native speaker judgments. When averaged across all tasks,
nonnative speaker performance did not overlap with native performance. However, several
variables correlated significantly with outcome, including suprasegmental training, which
indicated performance closer to native level.
The influence of first language on the processing of wh-movement in English as a second language
