Overview

Dyscalculia is a learning difference that affects mathematical abilities. This causes difficulty in understanding, processing, and utilising numerical information, that is not thought to be caused by low intelligence or insufficient schooling. Estimates vary by country, but studies suggest that between 3 to 6.5% of individuals may have dyscalculia.¹ It is often compared to dyslexia, which is another learning difference that causes difficulties in reading and writing. Studies have shown that the learning difference might be due to genetics (passed down through families) or caused by differences in brain development.²

Dyscalculia is usually first noticed during childhood. Children with dyscalculia could be performing well in other subjects, but underperforming in mathematics. It is often noticed that they fall behind during primary schooling and struggle to catch up if proper interventions are not used.

Symptoms of dyscalculia

So what are the symptoms of dyscalculia? The following list summarises the most common symptoms associated with this learning difference:³

• Poor mathematical ability, including difficulty understanding different mathematical concepts
• Poor understanding of signs and symbols
• Difficulty understanding fractions and place value
• Reversing or transposing numbers, meaning that you may switch around the order of multi-digit numbers
• Difficulty with pattern recognition

In addition to the mathematically related symptoms above, there can often be additional indicators that someone has dyscalculia that affect their wider life such as:⁴

• Poor posture and fatigue
• Difficulty sequencing events
• Difficulty with direction and time
• Difficulty spelling and reading
• Confusing left and right

Some symptoms may more obviously suggest dyscalculia, such as difficulty with various mathematical concepts, whereas others are less obvious and can affect your daily life without having such a strong link to mathematics. 

Symptoms of dyscalculia in adults and children

Both adults and children can have dyscalculia and symptoms can be similar across all ages, however, looking out for specific difficulties at different ages could help you identify if you or someone you know has dyscalculia. 

Early childhood

In early childhood, someone with dyscalculia may have difficulty recognising numbers and learning to count, as well as problems with basic arithmetic operations such as addition and subtraction. The most common issue seen in children with dyscalculia is ‘number sense’, which is an intuitive understanding of how numbers work, for example being able to estimate and compare quantities on a number line, as well as having difficulty understanding number words such as one, two, thirteen, forty and so on. 

The earliest appearance of dyscalculia often occurs as an inability to subitise, which is the ability to glance at a small group of objects and know how many are there without counting each one. Children as young as 5 years old should usually be able to subitise around 6 objects. If a child has dyscalculia, they will be able to subitise fewer objects and take longer to do so.

School-age children

Children of school age may struggle to understand mathematical concepts and rules such as times tables, as well as finding it challenging to solve maths problems and word problems like completing calculations. Often, children with dyscalculia will need to count on their fingers when adding numbers. At this age, it may cause maths-related anxiety, frustration, and a lack of confidence in their abilities. 

Adolescents and adults

In adolescents and adults, dyscalculia could look like continued difficulties with mental maths and arithmetic as well as struggling to apply mathematical concepts to real life such as budgeting, using measurements and following driving directions. This can often impact career decisions as well as job performance in this age group. 

Causes of dyscalculia 

Dyscalculia is hugely under-researched, therefore it is hard to pinpoint the exact causes of dyscalculia which differ from person to person.

Dyscalculia is thought to be caused mainly by genetic factors or due to the brain developing differently from normal, although there are other suggested causes. Mathematical disabilities resulting from some types of brain injuries would be classified as ‘acalculia’ or ‘acquired dyscalculia’ as opposed to true dyscalculia.

Genetic factors

Research has shown that children who have dyscalculia often have a parent who struggles with the same difficulties, suggesting the learning difference could have a hereditary aspect and be passed down through families.⁵

Research shows that the following genetic disorders have frequently been observed in people with dyscalculia. This suggests some possible genetic causes and an overlap with certain syndromes which may contribute to the learning difference:

• Turner’s syndrome - this is a genetic disorder which only affects people assigned female at birth (AFAB) and causes someone to have only one normal X sex chromosome (where normal individuals would have two X sex chromosomes if AFAB , or one X and one Y chromosome if assigned male at birth (AMAB)). Turner’s syndrome causes underdeveloped ovaries and a shorter-than-normal height 
• DiGeorge syndrome - this syndrome can cause learning and behavioural problems, a cleft lip or palate, heart and hormone problems, as well as issues with speech and hearing
• Williams syndrome - this is a rare genetic condition that can cause cognitive challenges, delayed development and cardiovascular abnormalities 
• Fragile X syndrome - this syndrome can cause difficulties with learning and development, behaviour, attention, emotional development, as well as issues with connective tissue 

Brain development factors

Using brain imaging to compare the brains of children and adults with and without dyscalculia, it has been observed that those with dyscalculia may have differences in grey matter of the brain, as well as differences in thickness, surface area, and volume in areas of the brain that are associated with carrying out mathematical processes, learning, memory and cognition. This suggests that there could be differences in development in these areas of the brain which could contribute to dyscalculia.

Environmental factors

There have been links made to dyscalculia and exposure to alcohol in the womb. Low birth weight as well as premature birth are thought to also play a role. These environmental factors likely link to abnormal or delayed brain development. 

Conditions that often coexist with dyscalculia

There are several conditions that often occur alongside dyscalculia or are frequently misdiagnosed as another condition instead of dyscalculia, such as:

• Dyslexia - this causes difficulties with reading and writing
• ADHD - this can cause restlessness and trouble concentrating
• Maths anxiety - some individuals get so anxious about doing maths that this fear and nervousness can lead to poor performance in maths tests
• Genetic conditions - some of the previously discussed genetic conditions including Turner’s syndrome and fragile X syndrome have been associated with dyscalculia

Diagnosis 

Criteria for appropriate diagnosis has not yet reached a consensus. Researchers are often required to rely on specific tests that look at things such as working memory, intelligence, inhibition, and executive function, in addition to teacher evaluations. 

As an alternative to this method of testing, it has been shown that fMRI scans of neurotypical children (those who have ‘normal’ brains and no learning differences or other conditions) can reliably be differentiated from dyscalculic children by looking at the activation in an area of the brain called the prefrontal cortex. Although this method is effective, it is often not used due to the cost and time needed to perform the testing. 

A combination of standardised tests, diagnostic tools and evaluation by teachers and professionals would be the typical assessment process, with the overarching criteria for diagnosis being persistent difficulty with maths, and comparatively low mathematical performance when compared to peers of a similar age. 

Treatment 

There is no medication for dyscalculia , however treating any co-occurring conditions such as ADHD or anxiety could be helpful in improving symptoms. 

Educational interventions could be helpful to minimise the disruption caused by dyscalculia. Assistive technologies could be helpful for use at school and at home, such as graphing tools, apps that work on basic number concepts, maths notation tools and graphic organisers for maths.

Summary

In summary, dyscalculia is a hugely under-researched and poorly understood condition with a large variety of possible causes ranging from genetics to brain development and environment. 

Due to dyscalculia largely being poorly understood, diagnosis is not yet standardised, however, health providers will often use a combination of mathematical testing as well as comparison with the performance of peers of the same age. An in-depth assessment is needed to make sure there is no misdiagnosis as there is some overlap with other conditions.