Korean Hangul is more robust to a serial bottleneck: Co-occurring and semantically related Korean words can be processed in parallel.

Can readers process multiple words simultaneously, and are there cultural differences in attentional bottleneck in lexical processing? To answer these questions, we asked participants to view two words and categorize only one (single-task) or both words (dual-task), using Korean word pairs that frequently co-occur and are semantically related. We hypothesized that the coactivation of related words could facilitate lexical processing, and that the unique characteristics of Korean Hangul, such as its shallow orthographic depth and clear-cut syllabic boundaries, would enhance this effect. The results suggest that Korean Hangul is more robust to a serial processing bottleneck. Unlike the previous findings in English, independent or unrelated Korean word pairs were not processed in a strictly serial manner. Furthermore, the results for co-occurring and semantically related words supported the parallel processing model. Interestingly, for regularly co-occurring words, accuracy for one word increased if the participant was also correct about the other. These findings suggest that the relation between the words and the properties of writing systems should be considered in the long-standing serial versus parallel debate in reading research. (PsycInfo Database Record (c) 2025 APA, all rights reserved).