Relationship Between Early and Later Developing Numerical Abilities

Principal Investigator: 
Project Overview
Background & Purpose: 

The focus of this project is to ask whether nonverbal numerical abilities that emerge early in human development serve as a foundation for learning mathematics? A large sample of 6-month-old infants will be tested in a new procedure that allows a quantification of each infant’s ability to see numerical differences. The sample will be tracked longitudinally and tested on a battery of mathematical tasks at 3.5 and 4.5 years of age.


The work is conducted in Dr. Brannon's infant cognition laboratory at Duke University in Durham, NC.

Research Design: 

This project has both a longitudinal and cross-sectional research design and will generate evidence that is associative/correlational [quasi-experimental] and causal [experimental]. Original data will be collected using survey research [structured interviewer-administered questionnaires], behavioral tasks that measure where and how long infants look, and touch screen behavioral tasks that assess accuracy and RT. Instruments or measures being used include infant behavioral looking time tasks, touch screen behavioral response tasks, TEMA 3, Picture Vocabulary Test – Fourth edition (PPVT-4), and Wide Range Intelligence Test (Glutting, Adams, Sheslow, 2000). Regression will be the main method to assess the relationship between the different measures. A sample size of 109 would be required in order to detect significance of the R2 for a multiple regression equation with three predictors (preference score from numerical change-detection, and learning parameter from anticipatory looking and/or touch-screen tasks), with power of .80 and a p of .01. With a sample size of 130 and a p < .01 we would be able to detect an effect size as small as R2 = .13.


Findings will be posted as they become available.

Publications & Presentations: 

Libertus, M., Brannon, E. (2010). Stable individual differences in number discrimination in infancy. Developmental Science.