An ERP Study on Attraction Effects in Advanced L2 Learners

In English, the rule of agreement is quite simple: verbs must agree with their subject head nouns in terms of number features. Despite this simplicity, agreement processing is always interrupted when the subject phrase of the sentence "The key to the cabinets is on the table," contains two nouns with a mismatch in number features commonly known as attraction effects. This study used event-related potentials (ERPs) to examine whether late advanced second language (L2) learners can acquire native-like sensitivity of attraction effects. The results revealed that L2 learners showed ERP patterns qualitatively similar to native English speakers: ungrammatical verbs following singular attractors elicited a P600 effect relative to their grammatical counterparts, whereas this positivity was replaced by an N400 effect when plural attractors intervened between the subject head nouns and the verbs. Of particular interest, given that, compared to native speakers, the amplitude of the P600 effect elicited by L2 learners was smaller, there was a quantitative difference between native speakers and L2 learners. We proposed that these two ERP components represented the two processing routes of agreement: the P600 effect indexed a full, combinatorial process, which parsed morphosyntactic features between agreement controllers and targets, whereas the N400 effect indexed a shallow, heuristic process, which evaluated lexical associations between agreeing elements. Moreover, similar to native speakers, advanced L2 learners showed an asymmetrical pattern of attraction effects, in that plural attractors were interfered with ungrammaticality at disagreeing verbs, but they did not cause any difficulties in processing grammatical sentences at agreeing verbs. The overall results suggested that compared to native processing, L2 processing of complex agreement with attractor interference was shallower and therefore late advanced L2 learners could not achieve native-like attraction effects.