Age of acquisition effects in Chinese two-character compound words: a megastudy of eye movements during reading

Words learned earlier in life are processed faster than words learned later in life. In Chinese, the age of acquisition (AoA) effect has been extensively studied in one-character words, yet no studies have explored this effect in compound words. Given that compound words are a widespread word type and are processed differently than one-character words, it is unclear how AoA affects compound word processing. The present study examined the role of multiple variables in the processing of Chinese two-character compound words based on a database of eye-movement measures. We focused on the AoA effect from the whole compound word and the first and second characters. We found that whole-word AoA and first-character AoA have an early and long-lasting influence, with no AoA effect from the second character. The results indicated that two-character compound words are accessed via the character and whole word simultaneously. These findings are discussed with respect to theories of the AoA effect.