During the second year of life, children acquire words and expand their receptive and expressive vocabularies at a rapid pace. At this age, toddlers' phonological abilities are also developing rapidly. The current study investigated the effect of phonological complexity of words on the order in which they are acquired, receptively and…

Fifty-one 23-to-55-month-old-infants faced two apparatuses that required the use of a rigid (box apparatus) or flexible (hose apparatus) stick-like tool to retrieve a toy stuck inside. Before attempting the extraction, however, they had to pick the only one tool (of three) on display that had the appropriate rigidity/flexibility to be effective.…

Despite the seemingly simple mapping between adjectives and perceptual properties (e.g., color, texture), preschool children have difficulty establishing the appropriate extension of novel adjectives. When children hear a novel adjective applied to an individual object, they successfully extend the adjective to other members of the same object…

Adults find negative sentences difficult to process, but an informative context can facilitate processing substantially, suggesting that much of this difficulty may come from the pragmatics of negation. Are children sensitive to the pragmatics of negation as well? Although children perform poorly on many tests of negation comprehension, we argue…

Background: Although verbal imitation can provide a valuable window into the developing language abilities of toddlers, some toddlers find verbal imitation challenging and will not comply with tests that involve elicited verbal imitation. The characteristics of stimuli that are offered to toddlers for imitation may influence how easy or hard it is…

For adults, "no" and "not" change the truth-value of sentences they compose with. To investigate children's emerging understanding of these words, an experimenter hid a ball in a bucket or a truck, then gave an affirmative or negative clue (Experiment 1: "It's not in the bucket"; Experiment 2: "Is it in the…

This cross-sectional study investigated the use of four verbal indices of social knowledge (personal pronouns, verb conjugations, people words and mental state language) and their concurrent relations in a sample of 287 Italian-speaking children between 18 and 36 months. Results showed that the production of all indices increased with age. Mental…

We examined children's task engagement during a challenging puzzle task in the presence of their primary caregivers by using a representative sample of rural children from six high-poverty counties across two states. Weighted longitudinal confirmatory factor analysis and structural equation modeling were used to identify a task engagement factor…

When learning verb meanings, learners capitalize on universal linguistic correspondences between syntactic and semantic structure. For instance, upon hearing the transitive sentence "the boy is glorping the girl," 2-year-olds prefer a two-participant event (e.g., a boy making a girl spin) over two simultaneous one-participant events (a…

This article describes the European Portuguese MacArthur-Bates Communicative Development Inventories short forms, the first published instruments for the assessment of language development in EP-learning infants and toddlers. Normative data from the EP population are presented, focusing on developmental trends for vocabulary learning, production…

The current study examined the role of increased attentional load in 24 month-old children's multistep problem-solving behavior. Children solved an object-based nonspatial working-memory search task, to which a motor component of varying difficulty was added. Significant disruptions in search performance were observed with the introduction of the…

Children's acquisition of tool use abilities is an important part of development but is not yet well understood. This study compares two modes of tool-use learning, observation and individual haptic experience. Two- and 3-year-olds had haptic experience with tools, observed tool use by others, had both haptic and observational experience, or no…

Existing research suggests a need for an intervention that can accelerate vocabulary acquisition for young children at-risk due to poverty. An adapted alternating treatments design was used to examine the effects of Dialogic Reading and Activity-Based Intervention (ABI) on participants' production of target words. Participants were three…

Psychometric and utility studies on Social Emotional Assessment Measure (SEAM), an innovative tool for assessing and monitoring social-emotional and behavioral development in infants and toddlers with disabilities, were conducted. The Infant and Toddler SEAM intervals were the study focus, using mixed methods, including item response theory…

This is the 36th Annual Report to Congress on the Implementation of the "Individuals with Disabilities Education Act," 2014. Section 664(d) of the "Individuals with Disabilities Education Act" ("IDEA") (P.L. 108-446), as reauthorized in 2004, requires that the Department of Education report annually on the progress…