Reversibility in Chinese word formation influences target identification.

We recorded event-related brain potentials during the processing of visually presented compound words in Mandarin Chinese. We capitalized on a particular characteristic of Chinese word formation, where two constituents can be combined in two different orders (A+B or B+A), yielding distinct meanings-so-called "reversible words". By investigating the impact of structural reversibility on the processing of compounds in Chinese during a lexical decision task, the present study revealed a pronounced difference between reversible and non-reversible words. Analyses revealed a more enhanced negativity (N400) for reversible words, reflecting demands during semantic processing, followed by a P300-like deflection for non-reversible words, which we interpret with respect to the ease of target identification due to target discriminability. The findings indicate that both character combinations (A+B, B+A) as well as access to the individual constituent meanings result in interference during the processing of reversible and non-reversible words. They reveal that combinatorial processes are affected by demands arising from competing representations (N400), and more importantly, that this impacts the task-relevant cognitive processes required in the current word/non-word identification task (P300). The observed P300-like potential suggests that the allocation of attentional resources is intertwined with combinatorial operations.