The process of learning a second language includes the acquisition of literacy skills. Currently, there is no standardized practice for teaching a new orthography, though research suggests that there are clear differences between languages with different orthographic depth, and the corresponding grain sizes that evolve as cognitive strategies. This study investigated the effects of two different instruction methods on reading outcomes for adult L2 learners of Russian. This study extends research done by Brennan & Booth (2015), which trained adults to read an artificial orthography. Here, we trained 34 literate English-speaking adults on Russian Cyrillic orthography with initial instruction that directed attention either to large or small grain size units (i.e., words or letters). After controlling for overall phonological skills, we found that small grain instruction resulted in higher accuracy for letter-phoneme matching, while large grain instruction led to greater accuracy with reading whole words in rime-rhyme foil trials. Additionally, differences among individual learners affected outcomes, as those in the large grain group who displayed greater phonemic skills also had slower reaction times. This same effect was not found for the small grain group, suggesting that these particular learners continued to apply small grain analysis even when large grains would have resulted in faster times. Overall, these results show that when adults are learning to read a second orthography, both large and small grain instruction can be beneficial in facilitating the development of accurate and efficient reading ability, thereby allowing the learner to use literacy as a scaffold for oral language development including vocabulary growth and increased grammar knowledge in order to improve L2 proficiency
