Number line estimation (NLE) tasks are widely used to investigate numerical cognition, learning, and development, and as an instructional tool. Interpretation of these tasks generally involves an implicit expectation that responses are driven by the overall magnitudes of target numerals, in the sense that the particular digits conveying those…

In four experiments, we investigate how the ability to detect irrelevant explanations develops. In Experiments 1 and 2, 4- to 8-year-olds and adults rated different types of explanations about "what makes cars go" individually, in the absence of a direct contrast. Each explanation was true and relevant (e.g., "Cars have engines that…

Recent research has shown that from early in development, children selectively form new beliefs in response to information supplied by others. However, little is known about the development of selective revision of existing beliefs in response to socially conveyed information. Such selective social belief revision has been extensively studied by…

When reasoning about a representation (e.g., a toy lion), children often engage in "iconic realism," whereby representations are reported to have properties of their real-life referents. The present studies examined an inverse difficulty that we dub "representational disregard": overlooking (i.e., disregarding) a…

Developmental theory has long emphasized the importance of linking perception, cognition, and action. Techniques designed to record the spatial and temporal characteristics of hand movements (i.e., "manual dynamics") present new opportunities to study the nature of these links across development by providing a window into how perceptual,…

Warning others is a paradigm case of communicative helping and prospective action understanding. The current study addressed the ontogeny of warning in infants' gestural communication. We found that 12- and 18-month-olds ("n" = 84) spontaneously warned an adult by pointing out to her an aversive object hidden in her way…

Children aged 3 to 8 years old and adults were tested on a reality–fantasy distinction task. They had to judge whether particular entities were real or fantastical, and response times were collected. We further manipulated whether the entity is a specific character or a generic fantastical entity. The results indicate that children, unlike adults,…

Most adults experience childhood amnesia: They have very few memories of events prior to 3 to 4 years of age. Nevertheless, some early memories are retained. Multiple factors likely are responsible for the survival of early childhood memories, including external representations such as videos, photographs, and conversations about past experiences,…

This research explores whether young children are sensitive to speaker gender when learning novel information from others. Four- and 6-year-olds ("N" = 144) chose between conflicting statements from a male versus a female speaker (Studies 1 and 3) or decided which speaker (male or female) they would ask (Study 2) when learning about the functions…

The abilities of past and future episodic thinking develop hand in hand across the preschool years and are intimately connected in adults. Little is known, however, about the development of episodic thinking in middle childhood and how it is influenced by sociocultural factors. In the present study, one hundred sixty-seven 7- to 10-year-old…

Two experiments investigated how young children and adults understand whether objects are "by" a landmark and remember their locations. Three- and 4-year-old children and adults were asked to judge whether several blocks were "by" a landmark. The blocks were arranged so that their absolute and relative distances from the landmark varied. Later,…

We conducted four experiments to examine developmental differences in preferences for using color, size, and location information to disambiguate hiding places. Three- and 4-year-olds and adults described how to find a miniature mouse that was hidden in one of two highly similar small objects in a dollhouse. In Experiment 1, the hiding places…

Five-year-olds, 5 1/2-year-olds, 6-year-olds, and adults were tested for the presence of two intuitions about thinking hypothesized to be part of the adult theory of mind (a) when engaged in a mentally demanding activity, a person's thinking will be directed toward that activity, and (b) when the activity is not mentally demanding, the person's…

This experiment tested whether children's insight into a difficult symbolic relation could be increased by explicitly emphasizing the intentionality surrounding the artifact's creation and use. Specifically, I explicitly emphasized (a) the adult's intent to communicate information via the artifact and (b) the artifact's intentional origins and…

The articles in this collection consider one very interesting puzzle of development: U-shaped developmental functions. At some point during development, an organism might exhibit what seems like a regression from its expected developmental trajectory and, according to continuity models of development, this is aberrant. In this special issue,…