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David H Rakison

Publications and source records attributed to David H Rakison.

7 recordsLinked to original sources
PubMed2006

Make the first move: how infants learn about self-propelled objects.

In 3 experiments, the author investigated 16- to 20-month-old infants' attention to dynamic and static parts in learning about self-propelled objects. In Experiment 1, infants were habituated to simple noncausal events in which a geometric figure with a single moving part started to move without physical contact from an identical geometric figure that possessed a single static part. Infants were then tested with an event in which the parts of the objects were switched. In Experiments 2 and 3, infants were habituated and tested with identical events except that the part possessed by each object during habitation was switched relative to the first experiment. Results of the experiments revealed that 16-month-olds failed to encode the relation between an object's part and its onset of motion, 18-month-olds were unconstrained in the relations involving self-propulsion that they would encode, and 20-month-olds were constrained in the relations they would encode. The results are discussed with regard to the developmental trajectory of learning about motion properties and the mechanism involved in early concept acquisition.

Age Factors↗
PubMed2005

A secret agent? How infants learn about the identity of objects in a causal scene.

Four experiments examined the role of correlations between dynamic and static parts on 12- to 16-month-olds' ability to learn the identity of agents and recipients in a simple causal event. Infants were habituated to events in which objects with a dynamic or static part acted as an agent or a recipient and then were tested with an event in which the part-causal role relations were switched. Experiment 1 revealed that 16-month-olds, but not 12-month-olds, associate a dynamic part with the role of agent and a static part with the role of recipient. Experiment 2 showed that 12- and 16-month-olds do not associate a static part with the role of agent or a dynamic part with the role of recipient. Experiment 3 demonstrated that 14-month-olds will learn the relations presented in Experiment 1 and Experiment 2. Experiment 4 revealed that 12-month-olds were able to discriminate the two geometric figures in the events. The results are discussed with respect to infants' developing ability to attend to correlations between dynamic and static cues and the mechanism underlying early object concept acquisition.

Cognition↗
PubMed2004

Developing knowledge of objects' motion properties in infancy.

Three experiments with a novel variation of the inductive generalization procedure examined 18- and 22-month-olds' knowledge of objects' motion properties. Infants observed simple air and land movements modeled with an appropriate category member (e.g. dog) or an ambiguous block and were allowed to imitate with one or more of four exemplars. The experiments show that 18-month-olds' knowledge of land motions is grounded in causally relevant object parts, whereas 22-month-olds relate such motions more broadly to appropriate category members. Infants' basis for generalizing air motions suggested that at 22 months they have little knowledge about objects from that domain. The results are discussed in relation to the early development of the animate-inanimate distinction and the nature of the inductive generalization task.

Child, Preschool↗
PubMed2004

Infants' sensitivity to correlations between static and dynamic features in a category context.

Four experiments with the habituation procedure investigated 14-22-month-olds' ability to attend to correlations between static and dynamic features embedded in a category context. In Experiment 1, infants were habituated to four objects that exhibited invariant relations between moving features and motion trajectory. Results revealed that 14-month-olds did not process any independent features, 18-month-olds processed individual features but not relations among features, and 22-month-olds processed relations among features. In Experiment 2, 14-month-olds differentiated all of the features in the events in a simpler discrimination task. In Experiments 3a and 3b, 22-month-olds failed to show sensitivity to correlations between dynamic and static features in a category context. In Experiment 4, 22-month-olds, but not 18-month-olds, generalized the learned feature-motion relation to a novel instance. The results are discussed in relation to infants' developing ability to attend to correlations, constraints on learning, category coherence, and the development of the animate-inanimate distinction.

Attention↗
PubMedDate not supplied

You go this way and I'll go that way: developmental changes in infants' detection of correlations among static and dynamic features in motion events.

Four experiments utilizing the habituation procedure examined 10- to 18-month-olds' ability to detect and encode correlations among features in a motion event (N = 136). Infants were habituated to two events in which objects-with distinct parts and a distinct body-moved across a screen along a rectilinear or curvilinear motion path. Infants were then tested with one familiar event and three events in which one feature of the object (parts, body, or motion path) was presented in a novel combination with the other features. The results of the experiments revealed that 10-month-olds process independently static features in an event, but do not process correlations among dynamic features; whereas 14-month-olds detect the correlation between an object's parts and its motion trajectory, but only when the movement of parts is correlated with the motion of the object. Further, the data show that 18-month-olds detect correlations between all three features when the parts of the object move, but they detect only the relation between parts and motion path when the parts do not move. It is proposed that infants develop representations for the static and dynamic properties of objects through a sensitive perceptual system that detects individual features, whole objects, and movement properties, and a domain-general associative learning mechanism that encodes independent features and correlations among features.

Child Development↗