Language input and word morphology in Wichi acquisition

TAVERNA, A. S.

Praga

Congreso; Congreso de la International Association for the Study of child Language; 2024

IASCL

A central variable in language acquisition is the structure of the language being acquired. Because polysynthetic languages, present special 'extraction puzzles' due to the length of their words, several hypotheses about children's strategies for acquiring morphology (e.g., perceptual predominance vs. morphological boundaries) have been proposed. Wichi, an understudied complex morphological language, provides important evidence to contribute to this question. Here, we focus on the developmental trajectory underlying the acquisition of verb and noun morphology in children learning Wichi as first language. We used spontaneous speech data from a longitudinal study with three children aged 1;0-3;6 years (1 to 2.5 MLU) and input from the environment. Our developmental analysis focuses on:(1) the nouns and verbs produced by each target child and those produced in their input (types and tokens), (2) the nominal and verbal affixes produced by each target child (types and tokens), and (3) features of maternal speech. The results show that Wichi learners produce uninflected word stems: when the MLU barely exceeds 1 (1.05-1.17), nominal and verbal affixes (type and tokens) account for only 4% of the total number of nouns and verbs produced during this period. However, once children approach an MLU of 1.50, both nominal and verbal affixes (type and tokens) account for 20% of the total number of nouns and verbs. Among nominal affixes, possessive pronominal prefixes for alienable and inalienable nouns, deixis referring to spatial orientation, and evaluative morphology were observed during this period. Among verbal affixes, we found evidence for pronominal pronouns for both subject and object. None of the caregivers seemed to change the complexity of their Wichi for the benefit of the children. These results are discussed in terms of the role of phonological criteria in the segmentation of words, the importance of distributional learning and semantic criteria, and the role of maternal speech in the acquisition of polysynthetic languages.