Dr. Justin Halberda, Johns Hopkins University – Numbers Sense and Age

Sep 21, 2012

In today’s Academic Minute, Dr. Justin Halberda of Johns Hopkins University examines how our ability to work with numbers changes over time.

Justin Halberda is an associate professor of psychological and brain sciences at Johns Hopkins University where his research is focused on language acquisition and the organization of attention. He directs two laboratories that frequently work together, the Laboratory for Child Development and the Vision and Cognition Lab. He holds a Ph.D. in cognitive psychology from New York University.

About Dr. Halberda

Dr. Justin Halberda – Numbers Sense and Age

The term “number sense” is used to describe our ability to intuitively size up – without counting -- the quantity of objects, sounds, or people in our environments. For instance, number sense might help us to quickly find the shortest E-Z Pass lane when we are late for work, or to figure out whether the number of items in our shopping cart qualifies us to use the supermarket express lane. This is a very basic ability that we use every day, and scientists believe that we are born with it. But, being born with something does not mean that it can’t change. Until recently, it has been very difficult for scientists to study how cognitive abilities like number sense may change throughout our lives, because studying people across the full lifespan is challenging to pull-off in a lab setting.

 In a recent study published in the Proceedings of the National Academy of Sciences, we used the Internet to collect data on the number sense of more than 10,000 people, between 11 and 85 years of age. These people chose to log on to a webpage to test their own number sense and to help us with our research.

Two patterns emerged. First, we found that the precision of a person’s number sense improved throughout the school years and peaked at around age 30. This surprised us, because that’s a full decade after most other human cognitive abilities reach their best. Second, we found that throughout the human lifespan, number sense precision is related to how well a person does in school mathematics classes. In other words, a person whose number sense tested as more precise also reported having done well on the math portion of the SAT.

These results are intriguing because they tell us that not all cognitive abilities are at their best when we are young. They also suggest that number sense is malleable, leaving open the possibility of developing educational strategies to help improve it and with it, perhaps, school math performance.