The case against newborn imitation grows stronger.

The claim that human newborns imitate is widely accepted and influential. Yet reliable evidence that newborns match modeled behaviors is limited, and there is no empirically based explanation of how the knowledge that imitation requires could develop before birth. In their target article, Keven & Akins (K&A) contribute important new evidence to an alternative account of newborns' matching that challenges the newborn imitation claim.

Relations among early object recognition skills: Objects and letters.

Human visual object recognition is multifaceted, with several domains of expertise. Developmental relations between young children's letter recognition and their 3-dimensional object recognition abilities are implicated on several grounds but have received little research attention. Here, we ask how preschoolers' success in recognizing letters relates to their ability to recognize 3-dimensional objects from sparse shape information alone.

Using the axis of elongation to align shapes: developmental changes between 18 and 24 months of age.

An object's axis of elongation serves as an important frame of reference for forming three-dimensional representations of object shape. By several recent accounts, the formation of these representations is also related to experiences of acting on objects. Four experiments examined 18- to 24-month-olds' (N=103) sensitivity to the elongated axis in action tasks that required extracting, comparing, and physically rotating an object so that its major axis was aligned with that of a visual standard.

Some views are better than others: evidence for a visual bias in object views self-generated by toddlers.

How objects are held determines how they are seen, and may thereby play an important developmental role in building visual object representations. Previous research suggests that toddlers, like adults, show themselves a disproportionate number of planar object views - that is, views in which the objects' axes of elongation are perpendicular or parallel to the line of sight. Here, three experiments address three explanations of this bias: (1) that the locations of interesting features of objects determine how they are held and thus how they are viewed; (2) that ease of holding determines object views; and (3) that there is a visual bias for planar views that exists independently of holding and of interesting surface properties.

Human toddlers' attempts to match two simple behaviors provide no evidence for an inherited, dedicated imitation mechanism.

Influential theories of imitation have proposed that humans inherit a neural mechanism - an "active intermodal matching " (AIM) mechanism or a mirror neuron system - that functions from birth to automatically match sensory input from others' actions to motor programs for performing those same actions, and thus produces imitation. To test these proposals, 160 1- to 2½-year-old toddlers were asked to imitate two simple movements- bending the arm to make an elbow, and moving the bent elbow laterally. Both behaviors were almost certain to be in each child's repertoire, and the lateral movement was goal-directed (used to hit a plastic cup).

Changes in visual object recognition precede the shape bias in early noun learning.

Two of the most formidable skills that characterize human beings are language and our prowess in visual object recognition. They may also be developmentally intertwined. Two experiments, a large sample cross-sectional study and a smaller sample 6-month longitudinal study of 18- to 24-month-olds, tested a hypothesized developmental link between changes in visual object representation and noun learning.

Vision for action in toddlers: the posting task.

Three experiments examine 18- to 24-month-old (N = 78) toddlers' ability to spatially orient objects by their major axes for insertion into a slot. This is a simplified version of the posting task that is commonly used to measure dorsal stream functioning. The experiments identify marked developmental changes in children's ability to preorient objects for insertion, with 18-month-olds failing completely and 24-month-olds succeeding easily.

Parts and Relations in Young Children's Shape-Based Object Recognition.

The ability to recognize common objects from sparse information about geometric shape emerges during the same period in which children learn object names and object categories. Hummel and Biederman's (1992) theory of object recognition proposes that the geometric shapes of objects have two components-geometric volumes representing major object parts, and the spatial relations among those parts. In the present research, 18- to 30-month-old children's ability to use separate information about object part shapes and part relations to recognize both novel (Experiment 1) and common objects (Experiment 2) was examined.

Symbolic play connects to language through visual object recognition.

Object substitutions in play (e.g. using a box as a car) are strongly linked to language learning and their absence is a diagnostic marker of language delay.

Young children's haptic exploratory procedures.

Adults vary their haptic exploratory behavior reliably with variation both in the sensory input and in the task goals. Little is known about the development of these connections between perceptual goals and exploratory behaviors. A total of 36 children ages 3, 4, and 5 years and 20 adults completed a haptic intramodal match-to-sample task.

Developmental change in young children's use of haptic information in a visual task: the role of hand movements.

Preschoolers who explore objects haptically often fail to recognize those objects in subsequent visual tests. This suggests that children may represent qualitatively different information in vision and haptics and/or that children's haptic perception may be poor. In this study, 72 children (2½-5 years of age) and 20 adults explored unfamiliar objects either haptically or visually and then chose a visual match from among three test objects, each matching the exemplar on one perceptual dimension.

Early biases and developmental changes in self-generated object views.

Object recognition depends on the seen views of objects. These views depend in part on the perceivers' own actions as they select and show object views to themselves. The self-selection of object views from manual exploration of objects during infancy and childhood may be particularly informative about the human object recognition system and its development.

The development of imitation in infancy.

An overview of existing data on imitation in infancy suggests that changes in the direction of imitation research are underway. The widely accepted view that newborn infants imitate lacks supporting evidence. Instead, existing data suggest that infants do not imitate others until their second year, and that imitation of different kinds of behaviour emerges at different ages.

Imitation in infancy: the development of mimicry.

Parents of 162 infants ages 6 to 20 months modeled subsets of four of the same set of eight behaviors, each for a maximum of 3 min, and encouraged their infants to imitate. Proportions of infants producing each behavior (a) when it was modeled and (b) during modeling of a different behavior were compared to estimate the age at which infants mimicked each kind of behavior. No reproduction of these motor acts--that is, no mimicry--was observed at 6 months.

Exploration or imitation? The effect of music on 4-week-old infants' tongue protrusions.

In a newborn imitation paradigm, an auditory stimulus--music--replaced the standard adult behavioral model. Alternating intervals of music and silence affected 4-week-old infants' rates of tongue protruding--evidence that tongue protruding is a general response to interesting distal stimuli.

Object name learning and object perception: a deficit in late talkers.

Two experiments examined the relation between early object name learning and the ability to represent objects by their abstract shapes. In Experiment 1, two-year-old children with productive vocabularies in the bottom 20th percentile--'late talkers'--were compared with (1) same-age children with larger vocabularies, and (2) younger children matched for productive vocabulary, on their ability to recognize named common objects. Object categories were represented two ways: by lifelike, perceptually rich toys, and by grey caricatures of those objects' abstract shapes.

Whose DAM account? Attentional learning explains Booth and Waxman.

Booth and Waxman (Cognition 84 (2002) B11) have recently shown that linguistic cues to animacy affect children's novel name extensions. They argue that this demonstration contradicts two central tenets of our attentional learning account of object naming, which Booth and Waxman characterize as the "dumb attentional mechanism" or "DAM" account. In the present article, we show that the first of these tenets has never been a feature of the attentional learning account, and that the second tenet, which is central to our account, is not addressed by Booth and Waxman's findings.

Object name learning provides on-the-job training for attention.

By the age of 3, children easily learn to name new objects, extending new names for unfamiliar objects by similarity in shape. Two experiments tested the proposal that experience in learning object names tunes children's attention to the properties relevant for naming--in the present case, to the property of shape--and thus facilitates the learning of more object names. In Experiment 1, a 9-week longitudinal study, 17-month-old children who repeatedly played with and heard names for members of unfamiliar object categories well organized by shapeformed the generalization that only objects with ith similar shapes have the same name.

Onset of Voluntary Communication: Smiling Looks to Mother.

Playing infants often direct smiling looks toward social partners. In some cases the smile begins before the look, so it cannot be a response to the sight or behavior of the social partner. In this study we asked whether smiles that anticipate social contact are used by 8- to 12-month-old infants as voluntary social signals.