To learn more about research in the Cognitive Development Lab or to get involved, please visit our new lab website. Visit my Publications page for more detailed research reports.

My research is in the general area of cognitive development, and I am interested in some of the basic questions of cognitive science. How general-purpose are the perceptual and cognitive processes that exist in our minds, and how content-specific? What kinds of knowledge can exist independent of language, and do these kinds exist in similar forms across many different species and developmental periods? What role might preverbal knowledge play in the thought processes of children and adults, and how is it integrated with culturally transmitted knowledge? To what extent does abstract thought depend on language, and how do we come to learn concepts that are foreign to minds without sophisticated language skills? My lab approaches these questions by focusing mainly on the perceptual and cognitive processing of quantity as a case study, though we also work in several other areas. We conduct behavioral research with preschool children, school-aged children, and adults, and our work is informed by a rich literature on perception and cognition in human infants and nonhuman animals.

Though it is a common assumption that numbers and mathematics are unique to educated humans, there are sophisticated capacities for quantitative thinking that don’t depend on human language and learning. These abilities are present in preverbal infants and nonverbal animals of many species, as well as in children and adults, and they even extend to the understanding of discrete quantity (number). This is surprising in part because number is a relatively abstract property of a set: three grapefruits take up more space than thirty grapes, but the set of thirty grapes is numerically larger. Yet human infants and nonhuman animals do indeed spontaneously base their behavior on approximate numerical quantity. Research suggests that the ability to mentally represent approximate number is common to many species of nonhuman animals and to humans of all cultures and developmental stages. These preverbal quantitative abilities do not simply disappear when we learn formal math. Their influence can be seen even in adults with many years of schooling, and they continue to affect quantitative thinking throughout life. Approximate quantitative abilities also underlie some aspects of children’s early math learning, and moreover they appear to be universal, cutting across barriers of race, class, and culture. For these reasons, a better understanding of the nature of these abilities, and how they become integrated with cultural tools such as school-based mathematics training, may lead to improvements in childhood education and in adult numeracy.