According to sources listed on both Understood.org and AboutDyscalculia.org, there is no universal consensus on the causes of dyscalculia. However there have been studies on what happens in the brains of dyscalculics while solving math problems. To understand this let’s first have a look at how children develop mathematic abilities in general.
By the time they are just three months old, babies are able to differentiate between large and small quantities. When they get to preschool, children learn number words to enable them to describe these quantities. In elementary school, they learn Arabic numerals, which will not make any sense without those number words from the previous stage. Finally, children develop a mental conception of numbers – an internal number line – which automates such judgments as large vs. small, and estimations. Read more