Poster C136, Sunday, March 26, 5:00 – 7:00 pm, Pacific Concourse
Neural representations of numerosity support the acquisition of counting in preschool children
Alyssa Kersey1, Jessica Cantlon1; 1University of Rochester
Prior to formal schooling, children’s numerical reasoning undergoes a fundamental change that allows them to map numerical symbols (e.g., number words) onto their quantitative meanings. There are no neural data examining counting acquisition in human children. Some behavioral work suggests that the evolutionarily-primitive approximate number system may play a role in the acquisition of numerical symbols, but behavioral work testing for a relation between indices of the approximate number system and number word acquisition has been inconclusive. In the current study we used functional magnetic resonance imaging (fMRI) to identify evolutionarily-primitive numerosity processing regions in adults and 3- to 5-year-old children during a numerosity comparison task. A contrast of difficult versus easy numerosity ratio revealed bilateral intraparietal sulcus (IPS), bilateral inferior frontal cortex, and anterior cingulate cortex (ACC). To identify whether those regions are also involved in the acquisition of verbal counting in these children, we measured changes in BOLD signal while those same participants listened to the verbal count sequence and the alphabet. The same IPS regions recruited for numerosity processing showed preferential activation for counting sequences compared to alphabet sequences in these children. This is the first neural evidence that evolutionarily-primitive numerosity processing regions of the brain are functionally related to the acquisition of verbal counting over child development. Additional analyses will explore the relation between counting ability and neural maturity.
Topic Area: THINKING: Reasoning