We examined event-related brain potentials (ERPs) during comprehension of the English Causative. The main goal was to examine ERP responses to grammatical violations that reflect a mismatch between the verb and the sentence structure. The second goal was to compare effects among native English speakers (NES) and native Spanish speakers learning English as a second language (ESL). We expected group differences to reflect different neurolinguistic processes, particularly for sentences that are well-formed in English, but not in Spanish.
The English Causative is a grammatical construction that is syntactically ditransitive ('SubjNP–V–ObjNP–PP') and means '[someone]–[CAUSED-by-doing-X]–[something]–[change-of-state]'. An example is the sentence, Jack sent his sister to the store, which implies that Jack (SubjNP) caused his sister (ObjNP) to undergo a change of location (PP) by sending her (V). Importantly, only certain verbs are permitted within this construction: In English, ditransitive verbs (e.g., send), are allowed, as are alternating unaccusatives, such as walk (Jack walked his sister to the store). Non-alternating unaccusatives, such as arrive, are disallowed, even when the sentence has a meaningful interpretation (*Jack arrived his sister to the store). To comprehend these structures as they unfold in time, a language-user must therefore reconcile word- and clause-level constraints and dynamically update his or her understanding throughout the sentence.
In the present study we asked nine NES and eight ESL participants to view a series of sentences, presented one phrase at a time, while we recorded their EEG. Each sentence was intransitive ('SubjNP–V' ), transitive ('SubjNP–V–ObjNP'), or ditransitive ('SubjNP–V–PP'), and was followed by a response probe. The task was to say whether each sentence was acceptable. Brain activity was measured using electroencephalography (EEG) and processed to create ERPs. We had four predictions. First, we predicted that the ObjNP following an intransitive verb would elicit a P600 effect, reflecting a syntactic violation (e.g., *Jack walked/arrived his sister). Second, for non-alternating (arrive-type) verbs, we predicted that a subsequent PP (e.g., *Jack arrived his sister to the store) would elicit a P600 effect, whereas Alternating (walk-type) verbs would elicit a minimal or no P600. Third, we expected that ESL partiticpants, like NES participants, would show an P600 effect to the ObjNP for sentences containing intransitives. However, in contrast with English, we predicted that the final PP would elicit an error-related response among ESL participants for walk-type verbs, as well as for arrive-type verbs.
Study results partly confirmed our predictions. The two groups showed similar patterns of acceptability, although ESL participants were slower overall. As predicted, the ObjNP elicited a P600 effect for arrive-type verbs for NES participants. Interestingly, ESL participants exhibited N400 rather than P600 effects to the ObjNP. Further, in response to the PP, both groups exhibited N400 effects to arrive-type verbs, without a subsequent P600 effect.
In summary, although their behavioral patterns did not differ, ERPs revealed group differences in verb–construction mismatches at different points in the sentence. The pattern of N400 and P600 responses was partly unexpected. We consider implications for syntax-semantic interactions, integration of word- and clause-level information, second-language learning, and functional correlates of N400 and P600 effects.
Available at: http://works.bepress.com/gtaylor_brooks/1/