First Language Attrition Induces Changes in Online Morphosyntactic Processing and Re‐Analysis: An ERP Study of Number Agreement in Complex Italian Sentences

Abstract

First language (L1) attrition in adulthood offers new insight on neuroplasticity and the role of language experience in shaping neurocognitive responses to language. Attriters are multilinguals for whom advancing L2 proficiency comes at the cost of the L1, as they experience a shift in exposure and dominance (e.g., due to immigration). To date, the neurocognitive mechanisms underlying L1 attrition are largely unexplored. Using event‐related potentials (ERPs), we examined L1‐Italian grammatical processing in 24 attriters and 30 Italian native‐controls. We assessed whether (a) attriters differed from non‐attriting native speakers in their online detection and re‐analysis/repair of number agreement violations, and whether (b) differences in processing were modulated by L1‐proficiency. To test both local and non‐local agreement violations, we manipulated agreement between three inflected constituents and examined ERP responses on two of these (subject, verb, modifier). Our findings revealed group differences in amplitude, scalp distribution, and duration of LAN/N400 + P600 effects. We discuss these differences as reflecting influence of attriters’ L2‐English, as well as shallower online sentence repair processes than in non‐attriting native speakers. ERP responses were also predicted by L1‐Italian proficiency scores, with smaller N400/P600 amplitudes in lower proficiency individuals. Proficiency only modulated P600 amplitude between 650 and 900 ms, whereas the late P600 (beyond 900 ms) depended on group membership and amount of L1 exposure within attriters. Our study is the first to show qualitative and quantitative differences in ERP responses in attriters compared to non‐attriting native speakers. Our results also emphasize that proficiency predicts language processing profiles, even in native‐speakers, and that the P600 should not be considered a monolithic component.

When the Second Language Takes the Lead: Neurocognitive Processing Changes in the First Language of Adult Attriters

“…In line with the interpretation that Attriters treated the two critical conditions as outright morphosyntactic violations, we found that Attriters’ acceptability ratings for the two unpreferred relative-clause conditions were not found to differ statistically from ratings the same participants provided in the same experimental session for outright morphosyntactic number agreement violations ( p s > 0.1, see Kasparian et al, 2016). Conversely, the same native-Controls provided significantly higher acceptability ratings for the RC word-orders than for number agreement violations presented in the same experimental session, indicating that they did indeed consider these RC word-orders as more grammatically acceptable than the Attriters.…”

“…The opposite was found in a recent ERP study of number agreement processing in Italian by Kasparian et al (2016). Although attriters (L1-Italian, L2-English) scored numerically lower on a number of written and oral proficiency measures, the only behavioral difference from native-controls that reached significance was the attriters’ longer response times during the online acceptability judgment task.…”

“…Further evidence that Attriters treated V-NP-o and NP-V-s sentences as morphosyntactic violations comes from the finding that their ratings for these sentences did not differ statistically from ratings the same participants gave in response to Italian number agreement violations during the same experimental session. In contrast, Controls rated V-NP-o and NP-V-s sentences higher than the number agreement violations (see Kasparian et al, 2016). These results suggest cross-linguistic influence from English (L2) word-order during Italian (L1) sentence-reading.…”

“…Eight experimental lists were created such that, across lists, each sentence contributed equally to each condition, while no sentence was repeated within any of the experimental lists. Each participant also saw 216 filler sentences, which were part of the larger study (testing number agreement and lexical-semantic processing) and will be reported in separated papers (Kasparian and Steinhauer, 2016; Kasparian et al, 2016). Out of the total of 324 pseudorandomized stimuli (108 experimental and 216 fillers) per participant, 146 sentences (approximately 45%) were acceptable (grammatically and semantically), while 178 were expected to receive a rating of 3 or lower on a five-point rating scale (approximately 55%).…”

Predictors of Language Dominance: An Integrated Analysis of First Language Attrition and Second Language Acquisition in Late Bilinguals

“…We limit the features we discuss to relatively global measures that can be compared between a bilinguals’ two languages and exclude more language-specific features, such as tense and aspect (e.g., Montrul, 2008) or number agreement (Kasparian et al, 2017). …”