Brain responses to semantic incongruity in bilinguals*1

Processing semantic anomalies in two languages: an electrophysiological exploration in both languages of Spanish–English bilinguals

“…The typical visual N400 congruity effect in young adults has a posterior focus and a slight right greater than left asymmetry, although this is not always the case even on average, much less on an individual by individual basis [29,50]. Although there is a tendency for bilinguals to show a different hemispheric pattern than monolinguals, data on this are mixed with some researchers finding no hemispheric differences in N400 amplitudes (Weber-Fox and Neville [52] at least for bilinguals exposed to the language after the age of 3) and others finding a slight left-lateralized N400 asymmetry [3,4,43]. This inconsis- Fig.…”

“…Specifically, ERPs were recorded to sentence final words in bilinguals reading sets of isolated sentences for meaning-separate blocks in English and in Spanish; in each block, a random half of the sentences ended sensibly whereas the other half ended with a semantically anomalous word. Not surprisingly, the onset and peak latencies of the N400 effect (ERPs to anomalous minus congruent endings)-an effect linked to semantic analysis-were delayed for the language in which bilinguals were less proficient (based on Boston Naming Test scores) [3,28,52]. At issue, however, is the extent to which this relative delay reflects differences in age of exposure to each language, current proficiency with it, or some combination thereof.…”

“…The N400 elicited by semantic anomalies in moderate-to-strongly constraining sentences peaks approximately 80-100 ms later (~500 ms) for fast (10 words/s) versus slower (one word/700 ms) presentation rates [24]. The N400 congruity effect also has been found to have a longer latency in bilinguals processing their less-dominant language [3], the one to which they were exposed later [28,52], or even to their first language when compared to monolinguals [3].…”

“…Ardal et al [3] presented English and French sentences, half ending with a semantic anomaly, to a group of bilinguals fluent in French and English, most of whom had English as a second language (L2). Participants read the sentences one word at a time for comprehension.…”

“…Nevertheless, one of the more consistent findings is a relative delay in the latency of the N400 effect for the less fluent or later acquired language [3,52]. The relative importance of age of exposure and/or language fluency on this bslowingQ of the brain's response to semantic anomalies (N400 latency) in a bilingual's second language (L2), however, remains uncertain.…”