Summary and Prospects: Processing of Semantic Incongruity In summary, all of the selected studies on L2 semantic processing reveal an enhanced

N400 as response to semantic incongruity. Differences concerning the N400 effect between monolingual and L2 processing appear quantitatively —i.e., the N400 effect is delayed and sometimes reduced in L2 learners’ ERPs, and additionally appears to be rather left than right-lateralized. All studies presume the integration view as the underlying functional role of enhanced N400 (see Chapter 2.2.1.1) and suggest that the quantitative differences are largely due to slower and less automatized processing with respect to L2 comprehension. In other words, L2 learners anticipate upcoming semantic information in their L2. The updating processes (i.e., integrating a word into the former context) appear more costly in L2 than in L1. The reasons for the enhanced processing costs in light of the AoA and proficiency levels of L2 learners remain unclear. As indicated above, results and interpretations are diverse. An open issue of most of these studies is the correlation between L2 learners’ AoA and proficiency level. For instance, the results derived by Weber-Fox and Neville seem problematic since the groups with AoA <11 may not be viewed in the same L2 setting as the groups with later AoA. In the latter, English can truly be considered as L2, while Chinese is the mother tongue of all these participants. Therefore, for the group 1–3, it is debatable to attribute the results to the L1 / L2 distinction as they could also be accounted for

language dominance. For those participants, Chinese seems to be the less dominant language and hence its status might be reconsidered with regard to language dominance rather than to the L1 / L2 distinction. It is less used and the mean results of the participants’ self-ratings affirm that English has always been the language with which

2. ERPs as Response to L1 and L2 Processing

they feel more comfortable. A connected though not similar group imbalance concerning language dominance appears in the study of Moreno and Kutas. Language dominance is highly correlated with AoA and proficiency. However, the authors offer a detailed correlation analysis unfolding the correlation and stating that both factors make contributions to the differences between L1 and L2 semantic processing when language dominance is taken into consideration. The study by Ojima et al. controls for possible AoA effects, indicating that proficiency may override the latency delay and trigger more automatized semantic processing. Their data show a delay of the N400 effect elicited by the low-proficiency L2 group, which appears to be an AoA-related effect that may be compensated by improving proficiency, as is indicated by the data of the high- proficiency L2 group. Newman et al. also controls for AoA and further apply proficiency as an internal group factor, thereby revealing differences in the proficiency influence on semantic processing within different groups (i.e., monolinguals and L2 learners). It is different from the interpretation given by Ojima et al. as the delay of the N400 latency in L2 learners is attributed to AoA influence, while proficiency may impact the distribution and the strength of the N400 effect.

Despite the small differences of the N400 effects between L1 and L2 processing for the latter, it somehow appears that both AoA and proficiency claim influence over this. Against this background, the present study intends to investigate the questions (i) whether and (ii) how the influences impact the L2 processing of semantic incongruity? As to (i), the present study takes up the idea that L2 learners are sensitive to incoming semantic information but show enhanced processing costs relative to the processes of updating the previous context with the anticipated new information. The enhanced L2 processing costs have been revealed by differences of the N400’s strength, distribution, and latency. The design of the present study is supposed to ensure any direct linking of both AoA and proficiency in terms of the strength, distribution, and latency of the potential N400 effect. According to question (ii), some of the above-reviewed data suggest a rather gradual than discontinuous influence of both factors. For instance, the results of the study by Newman et al study show that continuous improvement of proficiency gradually strengthens the N400 effect. The data of Ojima et al. suggests

2. ERPs as Response to L1 and L2 Processing

gradual development towards native-like latency of the N400 component (as response to incongruity) due to the improving L2 proficiency, albeit their categorical group design. Further, the data of Weber-Fox and Neville, who also group L2 learners, demonstrate a rather gradual latency change due to the increasing AoA. In order to provide valuable insights referring to the continuous character of influence, in the upcoming investigations both factors will be treated as continuous variables. Therefore, L2 learners will not be separated into groups on either AoA or proficiency bases. Chapter 4.2 comprises detailed descriptions of stimulus material, statistical models, hypotheses, and results for the processing of semantic incongruity by L1 speakers and L2 learners.