Neural underpinnings of orthography in first and second language readers

Osamu Takai
2019
Reading success in a second language (L2) is crucial for billions of people worldwide, but it is well known that it remains difficult for L2 learners to automatize the L2 processing in general. I investigated how long-term reading experience in a first language (L1) might change the neural L1 orthographic processing, and if these results can be generalized to L2 orthographic processing. I recruited adult monolingual English readers and adult Mandarin readers with late-language learning of
more » ... h. By contrasting single-letters with pseudoletter visual stimuli (a pseudoletter effect) in L1, the reaction time data showed that reading experience makes letter processing faster than in pseudoletter processing. The electroencephalogram data showed that the L1 pseudoletter effect was manifested in a left-dominant oscillatory activity and network dynamics. The electroencephalogram data also showed that the L1 pseudoletter effect was robust, regardless of the level of attention paid; letters elicited more of left-lateralized neural connectivity desynchronization than did pseudoletters. Additionally, the data from L2 showed that the magnitude of the L2 pseudoletter effect in the N170 in the left hemisphere was correlated with L2 proficiency. Taken together, I concluded that with reading experience, the brain has automatized orthographic processing, which is evidenced by being (1) more specific by shifting the processing demands to different neural regions within visual processing networks—left dominant for well experienced orthographies, (2) being more obligatory, at least, at the single-letter level, and (3) faster by completing the process of differentiating letters from pseudoletters at fairly early stages of visual processing. Further, I concluded that some of the above changes appear to be ready throughout adulthood; orthographic development appears to be free from the fossilization or critical period hypotheses.
doi:10.14288/1.0380819 fatcat:wbcxmokjdvdcllwib3qzbc7x2y