How children acquire knowledge of verb inflection is a long-standing question in language acquisition research. In the present study, we test the predictions of some current constructivist and generativist accounts of the development of verb inflection by focusing on data from two Spanish-speaking children between the ages of 2;0 and 2;6. The constructivist claim that children’s early knowledge of verb inflection is only partially productive is tested by comparing the average number of different inflections per verb in matched samples of child and adult speech. The generativist claim that children’s early use of verb inflection is essentially error-free is tested by investigating the rate at which the children made subject-verb agreement errors in different parts of the present tense paradigm. Our results show: 1) that, although even adults’ use of verb inflection in Spanish tends to look somewhat lexically restricted, both children’s use of verb inflection was significantly less flexible than that of their caregivers, and 2) that, although the rate at which the two children produced subject-verb agreement errors in their speech was very low, this overall error rate hid a consistent pattern of error in which error rates were substantially higher in low frequency than in high frequency contexts, and substantially higher for low frequency than for high frequency verbs. These results undermine the claim that children’s use of verb inflection is fully productive from the earliest observable stages, and are consistent with the constructivist claim that knowledge of verb inflection develops only gradually.

In this study, we apply MOSAIC (model of syntax acquisition in children) to the simulation of the developmental patterning of children's optional infinitive (OI) errors in 4 languages: English, Dutch, German, and Spanish. MOSAIC, which has already simulated this phenomenon in Dutch and English, now implements a learning mechanism that better reflects the theoretical assumptions underlying it, as well as a chunking mechanism that results in frequent phrases being treated as 1 unit. Using 1, identical model that learns from child‐directed speech, we obtain a close quantitative fit to the data from all 4 languages despite there being considerable cross‐linguistic and developmental variation in the OI phenomenon. MOSAIC successfully simulates the difference between Spanish (a pro‐drop language in which OI errors are virtually absent) and obligatory subject languages that do display the OI phenomenon. It also highlights differences in the OI phenomenon across German and Dutch, 2 closely related languages whose grammar is virtually identical with respect to the relation between finiteness and verb placement. Taken together, these results suggest that (a) cross‐linguistic differences in the rates at which children produce OIs are graded, quantitative differences that closely reflect the statistical properties of the input they are exposed to and (b) theories of syntax acquisition need to consider more closely the role of input characteristics as determinants of quantitative differences in the cross‐linguistic patterning of phenomena in language acquisition.

Los métodos experimentales para estudiar el desarrollo temprano han dominado la investigación en desarrollo cognitivo temprano durante las últimas décadas. La mayoría de las investigaciones se han llevado a cabo en laboratorios infantiles que utilizan la mirada de los bebés y niños pequeños como variable dependiente. Estos métodos han permitido acceder a información sobre capacidades cognitivas tempranas que anteriormente era impensable. En este trabajo revisamos, con una mirada crítica, las investigaciones que han utilizado dos métodos paradigmáticos: la habituación (en la variante llamada "violación de expectativas") y la preferencia visual intermodal. Ambos permiten, respectivamente, valorar los avances realizados en la investigación sobre capacidades perceptivas y representacionales, y desarrollo lingüístico. Discutimos aspectos metodológicos como la elección del diseño y las medidas de las variables dependientes. Asimismo, se revisan las interpretaciones de los datos procedentes de estas investigaciones y la difusión que han tenido para promover una visión determinada del desarrollo temprano.

Grinstead (2000) argues that there is a stage in both Spanish and Catalan children's grammatical development when they are restricted to using verbs without overt subjects. However, the evidence for a ‘no overt subject’ stage in early child Spanish is based on very thin data from a single child: Juan between the ages of 1;7 and 2;1. In the present note we reanalyse the data from Juan and compare it with data from another child María at 1;7 and 1;8. Our results show that Juan produces his first overt subject during the same session as his first non-imperative verb form, and that María produces a relatively high proportion of verbs with overt subjects in both of her first two transcripts. They thus provide no support for the claim that there is a ‘no overt subject’ stage in early child Spanish.

In the present study, children's early ability to organise words into sentences was investigated using the Weird Word Order procedure with Spanish-speaking children. Spanish is a language that allows for more flexibility in the positions of subjects and objects, with respect to verbs, than other previously studied languages (English, French, and Japanese). As in prior studies (Abbot-Smith et al., 2001; Chang et al., 2009; Franck et al., 2011; Matthews et al., 2005, 2007), we manipulated the relative frequency of verbs in training sessions with two age groups (three- and four-year-old children). Results supported earlier findings with regard to frequency: children produced atypical word orders significantly more often with infrequent verbs than with frequent verbs. The findings from the present study support probabilistic learning models which allow higher levels of flexibility and, in turn, oppose hypotheses that defend early access to advanced grammatical knowledge.