Purpose: Autistic individuals often face challenges perceiving and expressing emotions, potentially stemming from differences in speech prosody. Here we explore how autism diagnoses between groups, and measures of social competence within groups may be related to, first, children's speech characteristics (both prosodic features and amount of…

How early do children produce multiword utterances? Do children's early utterances reflect abstract syntactic knowledge or are they the result of data-driven learning? We examine this issue through corpus analysis, computational modeling, and adult simulation experiments. Chapter 1 investigates when children start producing multiword utterances;…

We trained a computational model (the Chunk-Based Learner; CBL) on a longitudinal corpus of child-caregiver interactions in English to test whether one proposed statistical learning mechanism--backward transitional probability--is able to predict children's speech productions with stable accuracy throughout the first few years of development. We…

This study examined the extent to which early intervention (EI) speech-language pathologists (SLPs) use and recommend language input strategies for caregivers of children with language delays and the child factors associated with these decisions. Participants included 213 SLPs who completed an online survey. Wilcoxon signed-rank tests, Friedman's…

Existing work on the acquisition of polarity-sensitive expressions (PSIs) suggests that children show an early sensitivity to the restricted distribution of negative polarity items (NPIs), but may be delayed in the acquisition of positive polarity items (PPIs). However, past studies primarily targeted PSIs that are highly frequent in children's…

Recent evidence suggests that deaf children with CIs exposed to nonnative sign language from hearing parents can attain age-appropriate vocabularies in both sign and spoken language. It remains to be explored whether deaf children with CIs who are exposed to early nonnative sign language, but only up to implantation, also benefit from this input…

In order for children to understand and reason about the world in an adult-like fashion, they need to learn that conceptual categories are organized in a hierarchical fashion (e.g., a dog is also an animal). While children learn from their first-hand observation of the world, social knowledge transmission via language can also play an important…

Parameter setting is either precipitous (Gibson & Wexler, 1994) or it is gradual in response to input frequency (Yang, 2002, 2004). In this study, we compare these models against the empirical domain of subject and (direct) object drop in Mandarin. We conducted a corpus-based study of the speech of 47 Mandarin-speaking children aged 1;2-6;5,…

Age of acquisition (AoA) is a measure of word complexity which refers to the age at which a word is typically learned. AoA measures have shown strong correlations with reading comprehension, lexical decision times, and writing quality. AoA scores based on both adult and child data have limitations that allow for error in measurement, and increase…

The words in children's language learning environments are strongly predictive of cognitive development and school achievement. But how do we measure language environments and do so at the scale of the many words that children hear day in, day out? The quantity and quality of words in a child's input are typically measured in terms of total amount…

The Less-Is-More hypothesis was proposed to explain age-of-acquisition effects in first language (L1) and second language (L2) learning. We scrutinize different renditions of the hypothesis by examining how learning outcomes are affected by (a) limited cognitive capacity, (b) reduced interference resulting from less prior knowledge, and (c)…

Language exposure plays a large role in language acquisition, and bilingual children must acquire both of their languages in environments that typically include abundant speech variability. The specific goals of this dissertation were to examine how speech exposure affected phonological retuning and lexical access in bilingual children's second…

The traditional Philadelphia allophonic /ae/ system (henceforth: PHL shown in (1) below) is characterized by a set of complicated conditioning factors and a dramatic acoustic distinction between the two allophones. In recent years, some Philadelphians have begun to exhibit a new allophonic system (NAS, shown in (2) below). Like PHL, NAS is…

Using augmented input might be an effective means for supplementing spoken language for children with autism who have difficulties following spoken directives. This study aimed to (a) explore whether JIT-delivered scene cues (photos, video clips) via the Apple Watch® enable children with autism to carry out directives they were unable to implement…

Many children diagnosed with autism spectrum disorder who receive early intervention reap developmental benefits, but little is known about characteristics of early intervention placements in the community that optimize individual growth. The extent to which children hear and use language, in particular, may contribute significantly to…