D. Dean Richards

The Development of Biological Knowledge: A Multi-National Study.

Abstract This study was designed to differentiate between universal and culturally specific aspects of childrens biological understanding. Kindergartners, second graders, and fourth graders from Israel, Japan, and the United States were asked whether people, other animals, plants, and inanimate objects possessed each of 16 attributes. The attributes included life, unobservable attributes of animals, sensory capacities, and attributes of all living things. The results indicated that children of all three ages in all three countries knew that people, other animals, plants, and inanimate entities were different types of things, with different properties. Children in all cultures were extremely accurate regarding properties of humans, somewhat less accurate regarding properties of other animals and inanimate entities, and least accurate regarding properties of plants. As predicted from cultural analyses, Israeli children were the most likely to fail to attribute to plants qualities that are shared by all living things. Also as predicted, Japanese children were the most likely to attribute to inanimate entities attributes possessed only by living things. In contrast to many previous findings, U.S. children in the study presented here displayed more accurate scientific knowledge than age peers in Japan or Israel. The results were analyzed in terms of how cultural beliefs and linguistic categories affect knowledge acquisition processes and scientific understandings.

Children's Understandings of the Attributes of Life.

Previous investigations of childrens understandings of the life concept have focused on their classifications of the life status of familiar objects. In this study, we attempted to examine more directly the processes by which children infer life status by examining their reasoning about unfamiliar objects. In Experiment 1, 4- to 11-year-olds and adults were asked to name attributes of living things to establish which attributes they associated most closely with life. Children age 7 and younger most often named attributes true only of animals but not of plants; older children more often named attributes true of both animals and plants. However, movement was the single attribute cited most frequently by children of all ages tested. In Experiment 2, 4- to 11-year-olds and adults were presented information about attributes of imaginary objects on a distant planet and were asked to infer if those objects were alive. Again, young children relied relatively heavily on qualities true only of animals but not of plants, whereas older children relied more on attributes true of both plants and animals. Also as before, movement was viewed as indicative of life at all ages tested. In Experiment 3, we examined the hypothesis that children discriminate among different types of motion and that the types of motion they associate with life are in fact typical of living things. Children ranging from age 5 through 11 were found to discriminate among different types of motion and to infer that objects were alive only when they showed the types of motion typical of living beings. The results of Experiment 3 allowed interpretation of seemingly conflicting results that have arisen in previous studies, as well as in Experiments 1 and 2 of the present study.

The episodic memory model of conceptual development: An integrative viewpoint

Recent trends toward the integration of prototypic and logical theories of concept representation have been combined with Andersons (1983) ACT* model of cognition to produce the episodic memory model of conceptual development. The episodic memory model suggests that the memory episode is the basis for concept representation. Semantic memory forms spontaneously when constellations of attributes are associated with each other in more than one episode. These attributes may gain enough strength so that they can be activated simultaneously in isolation of the original episodes, through the mechanism of spreading activation. Concepts are said to exist when any two or more objects, situations, or states share common associates in memory. The representation of a concept consists of those associates of the concept node that are currently part of working memory. Classification of a novel instance as a member of a particular concept depends upon whether the attributes of the concept that the subject encodes match associates of the concept node sufficiently to activate the concept node. Under this model, concept reasoning may be based on central tendency information, logical rules, or single episodes, depending upon which of these is activated in a particular task situation. Discussion focuses on the ramifications of the episodic memory model of concept development for such phenomena as Keil and Battermans (1984) characteristic to defining feature shift and the influences of context information on concept definitions.

The Role of the Functionality Rule in the Categorization of Well-Defined Concepts.

Abstract Two experiments were conducted to investigate whether children and adults could construct concept definitions by utilizing the mechanisms proposed by Richards and Goldfarbs (1986) episodic memory model. In Experiment I the question of whether children and adults were able to utilize hypothetical counterexemplar reasoning was examined. When given novel instances and asked to judge whether they were members of familiar categories, subjects attributed concept membership more often to objects possessing form features irrelevant to function than to objects possessing form features interfering with function or objects lacking the ability to function. Subjects justified their answers by referring to the influence of each attribute on the intended function of the object. Experiment 2 examined whether children utilized the functionality rule in making category judgments about novel concepts. Functionality was found to influence the judgments of both children and adults. Results are discussed in terms of Richards and Goldfarbs (1986) model and are related to other evidence that children possess theories about concepts.

The Development of Two Concepts

The purpose of this chapter is to explore ways in which we can characterize conceptual development. We will briefly examine existing approaches to studying the topic, point to their strengths and weaknesses, propose an alternative approach, and illustrate the alternative with examples involving children’s concepts of numbers and of life. The recurring theme will be that conceptual understanding is multifaceted, and that our approaches to studying it must be consistent with this fact.

The Relationship between the Attributes of Life and Life Judgments

This article describes preliminary results of a cross-cultural study of the relations between life judgments and beliefs about the attributes of living things. Research results suggest that Japanese children may extend attributes of living things more widely than American children of similar ages. It also appears that growth in logical classification capability is not what underlies developmental changes in judgments of whether objects are alive. Instead, such changes appear to stem from changes in knowledge of which categories of objects possess the traits of living things.

Dynamic Concepts and Functionality: The Influence of Multiple Representations and Environmental Constraints on Categorization

This article expands upon the episodic memory model delineated by Richards and Goldfarb. Previous research and observation are used to suggest that concepts should be viewed as dynamic and context-sen

Effects of Two Types of Familiarity on Children's Referential Communication Abilities.

Stimulus familiarity has been shown to facilitate childrens performance on referential communication tasks. The facilitative effects of stimulus familiarity could result either from prior stimulus recognizability or from immediate experience with experimental stimuli. The present study separated the effects of stimulus recognizability and experience. Kindergarten and third grade children communicated about both familiar and novel stimuli. Half the children were exposed to both types of stimuli prior to participation. The results indicated that older children chose the correct referent more often than younger children; children who received experience performed better than children who did not, and familiar stimuli were described more accurately than novel stimuli. The effects of stimulus recognizability and experience were independent. Third‐grade listeners were more likely to ask for additional information than kindergarten listeners, and third‐grade speakers tended to respond to such requests more ofte...