Serial processing of two words becomes parallel when they combine to form a compound word

According to one model of reading, words are recognized one at a time with serial shifts of focused attention. That serial strategy would be required if, as some prior research suggests, there is a bottleneck in the brain that cannot process two words simultaneously. Consistent with this serial model, we first show that participants can report lexical information about only one of two unrelated words that are flashed briefly above and below the point of gaze fixation and then masked. We then investigate whether two words that compose a single familiar compound word (e.g., bottle + neck) can nonetheless be processed in parallel. The results demonstrate that indeed, under the same conditions in which two unrelated words cannot be recognized simultaneously, accuracy for recognizing either or both of two words that form a compound exceeds the prediction of the serial model. This result complicates theories of a serial bottleneck in lexical access, especially in the context of natural reading when words often form meaning jointly.