Refining intervention: The acquisition of featural relations in object A-bar dependencies The presence of a [+NP] feature (representing a 'lexical restriction') on both the moved DP and the intervening subject is assumed to hinder children's comprehension of object A-bar dependencies (Friedmann et al. 2009). In order to better understand the nature and impact of this feature and its interaction with animacy, we assessed comprehension of object relative clauses and wh-questions in French-speaking children aged 5 to 11 using a character-selection task. Furthermore, we explored the link between processing of featural relations and working memory abilities through digit-span tasks. Results on questions straightforwardly confirm the role of the [+NP] feature; results on relatives suggest that the locality effect is sensitive to the formal similarity in D+NP shape of the target and the intervener. An animacy mismatch facilitates processing (as of age 7) only in the [+NP] condition, suggesting that the computation of locality draws on the structural expression of features, not just their mere semantic value. We argue in favor of a restrictive structural approach to intervention, and of a hierarchical organization of features. The link between accuracy and memory scores illustrates that limitations of computational resources affect processing of A-bar dependencies.

Children’s difficulties with dependencies involving movement of an object to the left periphery of the clause (object relative clauses/RCs and wh-questions), have been explained in terms of intervention effects arising when the moved object and the intervening subject share a lexical N feature (Friedmann, Belletti & Rizzi 2009). Such an account raises various questions: (1) Do these effects hold in the absence of a lexical N feature when the object and the intervener share other relevant features? (2) Do phi-features with a semantic role modulate such effects? (3) Does the degree of feature overlap determine a gradience in performance? We addressed these in three sentence-picture matching studies with French-speaking children (4;8 to 6;3), by assessing comprehension of (1) subject and object RCs headed by the demonstrative pronouns celui/celle and matching or mismatching in number; (2) object RCs headed by a lexical N and matching or mismatching in animacy; (3) object who- and which-questions. Our results show that mismatches in number, not in animacy, enhance comprehension of object RCs, even in the absence of a lexical N feature, and confirm previous findings that object who-questions yield better comprehension than object which-questions. Comparing across studies, the following gradation emerges with respect to performance accuracy: disjunction > intersection > inclusion. The global interpretation of these findings is that fine-grained phi-features determining movement are both sufficient and necessary for locality, and the degree of overlap of these features can capture the pattern of performance observed in children, namely higher accuracy as featural differences increase.

The aim of this study was to examine the acquisition and processing of multiple who- and which-questions in Romanian that display ordering constraints and involve exhaustivity. Toward that aim, typically developing Romanian children (mean age 8.3) and adults participated in a self-paced listening experiment that simultaneously investigated online processing and offline comprehension of multiple wh-questions. The study manipulated the type of wh-phrase (who/which) and the order in which these elements appear (subject–object [SO]/object–subject [OS]). The response to the comprehension question could address the issue of exhaustivity because we measured whether participants used an exhaustive or a non-exhaustive response. Our findings reveal that both children and adults slow down when processing who- as compared to which-phrases, but only adults show an online sensitivity to ordering constraints in who-questions. Accuracy is higher with multiple who- than which-questions. The latter pose more difficulties for comprehension, particularly in the OS order. We relate this to intervention effects similar to those proposed for single which-questions. The lack of intervention effects in terms of reaction times indicates that these effects occur at a later stage, after participants have heard the whole sentence and when they interpret its meaning.

Preschool children with neurotypical development (ND) trained on sentential complements (“X thinks/says that”) improve their Theory of Mind (ToM) performance. Can complementation training also enhance ToM in children with Autism Spectrum Disorder (ASD)? Thirty-three children with ASD (Mage = 8;11) and 20 younger ND peers (Mage = 4;3) were trained on sentential complements (4–6 weeks, 2–3 times per week, via the DIRE i-Pad App). Pre-training and post-training comparisons show that (1) training boosted both complementation and ToM performance across groups; (2) improvements remained 4–6 weeks after training ended; (3) participants with milder ASD symptoms made most gains. Training on sentential complements thus seems beneficial for addressing ToM difficulties in children with ASD, especially those with milder symptoms.