Dyscalculia () is a disability resulting in difficulty learning or comprehending arithmetic, such as difficulty in understanding numbers, learning how to manipulate numbers, performing mathematical calculations, and learning facts in mathematics. It is sometimes colloquially referred to "math dyslexia", though this analogy can be misleading as they are distinct syndromes.Dyscalculia is associated with dysfunction in the region around the intraparietal sulcus and potentially also the frontal lobe. Dyscalculia does not reflect a general deficit in cognitive abilities or difficulties with time, measurement, and spatial reasoning. Estimates of the prevalence of dyscalculia range between 3 and 6% of the population. In 2015 it was established that 11% of children with dyscalculia also have ADHD. Dyscalculia has also been associated with Turner syndrome and people who have spina bifida.Mathematical disabilities can occur as the result of some types of brain injury, in which case the term acalculia is used instead of dyscalculia which is of innate, genetic or developmental origin. Signs and symptoms
The earliest appearance of dyscalculia is typically a deficit in subitizing, the ability to know, from a brief glance and without counting, how many objects there are in a small group. Children as young as five can subitize six objects, especially looking at a die. However, children with dyscalculia can subitize fewer objects and even when correct take longer to identify the number than their age-matched peers. Dyscalculia often looks different at different ages. It tends to become more apparent as children get older; however, symptoms can appear as early as preschool.
Even with their best criterion, they found dyscalculia diagnoses for children longitudinally did not persist; only 65% of students who were ever diagnosed over the course of four years were diagnosed for at least two years. The percentage of children who were diagnosed in two consecutive years was further reduced. It is unclear whether this was the result of misdiagnosed children improving in mathematics and spatial awareness as they progressed as normal, or that the subjects who showed improvement were accurately diagnosed, but exhibited signs of a non-persistent learning disability. Persistence in adults
There are very few studies of adults with dyscalculia who have had a history of it growing up, but such studies have shown that it can persist into adulthood. It can affect major parts of an adults life. Most adults with dyscalculia have a hard time processing math at a 4th grade level. For 1st-4th grade level, many adults will know what to do for the math problem, but they will often get them wrong because of "careless errors", although they are not careless when it comes to the problem. The adults cannot process their errors on the math problems or may not even recognize that they have made these errors. Visual-spatial input, auditory input, and touch input will be affected due to these processing errors.