What's Different in Second-Language Processing? Evidence from Event-Related Brain Potentials

German sentences which were either correct, contained a selectional restriction violation, or a word category violation were presented auditorily to 16 native speakers of German (L1 group) and to 16 native speakers of Russian, who had learned German after the age of 10 (L2 group). Semantic violations elicited an N400 effect for both groups, but with a reduced amplitude and a longer peak latency in the L2 group. Compared to correct sentences, sentences with a phrase structure violation elicited an early anterior negativity followed by a broad centro-parietal positivity in native speakers. By contrast, there was no differential modulation of the early anterior negativity in the L2 group. A late positivity was also elicited in the second language learners, but it was slightly delayed compared to that shown by native speakers. This pattern is discussed in terms of different degrees of automaticity with respect to the subprocesses involved in sentence comprehension.