Ostensive definitions of words are ambiguities as to their referent. In a study of infant-mother dyads engaged in looking at picture books, 95 percent of ostensive definitions referred to the whole object depicted rather than parts, attributes, or actions. When parts were named, ambiguity was avoided by naming the part and the whole. (PJM)

Comments on the article by Jones and Smith in this issue. Responds to the theses that perceptual information is as much at the core of concepts as is nonperceptual information and that concepts are not represented as such but are computed on-line when needed. Presents a view of the relationship between perception and conceptual knowledge…

Comments on the article by Jones and Smith in this issue. Describes a program of research that demonstrates the important influence of perception on the structure of concepts. Proposes that both perceptual and nonperceptual information are important to conceptual structure throughout the continuum of knowledge acquisition and that perception is a…

Comments on the article by Jones and Smith in this issue. Outlines different perspectives from which the issue of conceptual development is approached, elaborating on the functions concepts serve and variations in those functions. Notes points of agreement with the perceptual knowledge view and offers comments on the research supporting the…

Research on reading has tried, and failed, to account for wide disparities in reading skill even among children taught by the same method. Why do some children learn to read easily and quickly while others, in the same classroom and taught by the same teacher, don't learn to read at all? In "Language Development and Learning to Read", Diane…