How do we process numbers? A new project from the Austrian Science Fund FWF hopes to find the complex answer to this seemingly simple question by building on the recent findings of a team from Innsbruck.
These show that while children and adults are equally good at processing numbers, they actually use different regions of the brain to do so.
The new project is now comparing the cerebral activity of children with and without numeracy deficits in order to arrive at a deeper knowledge of children's numerical and spatial magnitude processing.
What's more, 15 Smarties or 5 toy cars? Even if we restrict the concept of "more" to the number of objects, the brain requires a considerable degree of abstraction to answer this question, as the spatial dimensions of the objects must be isolated from their number. Though 15 Smarties may take up less space there are still "more" of them than 5 toy cars.
Dr. Liane Kaufmann of the Clinical Department of General Paediatrics at Innsbruck Medical University believes that answering questions like this is a typical numerical problem. "Computation is a team sport for the brain, as good numerical skills require the smooth interplay of different functional areas. Mathematical tasks require both numerical abilities and non-numerical ones, such as spatial skills", she said.
According to information published by Dr. Kaufmann and her team, this interplay changes as people grow up. Different areas of the brain are activated in adults than in children, even when solving simple numerical problems such as comparing one-digit numerals according to their numerical magnitude. Adults primarily use posterior (parietal) brain areas, while children rely predominantly on frontal regions. Dr. Kaufmann sees this as clear evidence of children's significantly more complex information processing activity - something which surprisingly does not affect the speed or accuracy of their solutions.
Dr. Kaufmann is using her 2005 Hertha Firnberg Prize to carry out further research into cerebral activity. This will allow her to focus on children with pronounced numeracy deficits. This phenomenon, known as dyscalculia, is actually as common as dyslexia, with between three and six percent of primary school children affected. The origins of dyscalculia are varied, but Dr. Kaufmann will concentrate on the form of the disorder associated with particular genetic defects.
Commenting on her research, Dr. Kaufmann said: "We have known for some time that numeracy deficits are often associated with certain genetic disorders, such as Turner Syndrome, Fragile X Syndrome and Williams Syndrome. As those affected also have difficulty processing spatial magnitude, we can learn a lot about the links between these two abilities by carefully observing their cerebral activity."
Functional magnetic resonance tomography is an important tool for the work of the group under Dr. Kaufmann. This method makes it possible to visualise the oxygen consumption of brain cells, thus giving a picture of the activities of different areas of the brain. Together with the analysis of behavioural data such as accuracy and speed in solving arithmetic problems, conclusions can also be drawn on the functional coordination of different brain regions. Dr. Kaufmann will carry out her comprehensive analysis by comparing children with and without numeracy deficits and will also differentiate between dyscalculia of genetic origin and isolated learning disorders without organic aetiology.
The question posed by this new FWF project will contribute to a better understanding of the brain's functional organisation and the processes involved in number processing and calculation. The findings will also be a starting point for developing effective intervention methods for children with dyscalculia.