Much of the research on object individuation in infancy has used a task in which two different objects emerge in alternation from behind a large screen, which is then removed to reveal either one or two objects. In their seminal work, Xu and Carey (1996) found that it is typically not until the end of the first year that infants detect a violation…

The following manuscript is a review of research surrounding best practices for language and literacy development in children birth to age three. Part 1 of the review begins with the research on language acquisition beginning in utero, continuing through infancy and onto the emergence of speech. The review discusses the importance of language…

The issue of whether young children use spatio-temporal information (e.g., movement of objects through time and space) and/or contact-mechanical information (e.g., interaction between objects) to search for a hidden object was investigated. To determine whether one cue can have priority over the other, a dynamic event that put these cues into…

The current study evaluated the relative roles of conceptual knowledge and executive control on the development of "categorical flexibility," the ability to switch between simultaneously available but conflicting categorical representations of an object. Experiment 1 assessed conceptual knowledge and executive control together; Experiment 2…

Standardized psychological assessment provides a precise yet limited view of the neuropsychological status of preschool toddlers, whose brain functioning is only beginning to develop localized functioning. Yet, referrals for preschool evaluation of these early-age children often request a wide variety of information about brain-behavior…

Experience with a variety of symbolic artifacts has been proposed as a mechanism underlying symbolic development. In this study, the parents of 120 2-year-old children who participated in symbolic object retrieval tasks completed a questionnaire regarding their children's naturalistic experience with symbolic artifacts and activities. In separate…

If after teaching a label for 1 object, a speaker does not name a nearby object, 3-year-olds tend to reject the label for the nearby object (W.E. Merriman, J.M. Marazita, L.H. Jarvis, J.A. Evey-Burkey, and M. Biggins, 1995a). In Studies 1 (5-year-olds) and 3 (3-year-olds), this effect depended on object similarity. In Study 2, when a speaker used…