Dyscalculia – Part IV: Heritability and the effects of brain damage on numerical abilities

"If identical twins are found to be sufficiently more concordant than fraternal twins,
then there is a significant contribution of genetic factors."
By Seonghae Jeon, M.P.A.

Before we come up with implementation methods through which we can utilize to effectively intervene the learning process of dyscalculic children, we should know what actually causes this condition to occur.


It is well-known that there is a specific genetic effect on standardized test of math and that school performance on all the measures is affected by shared environment for the effects of domain-general cognitive abilities. However, there is very little evidence that dyscalculia is inherited or unchanging, and for most people, it is congenitalthey are born with the condition.


To find evidence that dyscalculia may be inherited, psychologists and researchers conducted studies on twins by comparing the variance in the concordance of identical twins and fraternal twins to get an estimate of heritability. The assumption was, if the concordance is the same between the two groups of twins, then there is little or no contribution of heritability; if identical twins are found to be sufficiently more concordant than fraternal twins, then there is a significant contribution of genetic factors. 


Through multiple studies over several decadesthey concluded that there was a moderate to significant level of genetic influence on children’s mathematical ability along with their reading and linguistic abilities and IQ. They also stressed that a highly correlated factor called “generalist genes” affect all aspects of cognitive ability and disability and that non-shared, environmental influences operate as specialists and contribute to being bad at math.


In summary, continuity is genetic and change is environmental: age-to-age stability is primarily mediated genetically, whereas the environment contributes to change from age to age.  


Other studies show that arithmetical impairments and core deficits have been observed in many genetic conditions, including but not limited to, Turner’s Syndrome, Cerebral Palsy, and Williams Syndrome.


Children born very preterm ( more than 32 weeks) or extremely preterm ( less than 26 weeks) or with very low birth weight ( less than 1.5kg) are likely to show poorer academic performance at school especially at math and there appears to be a domain-specific deficit. Though there is no direct, cause-and-effect relationship between such birth conditions and incidence of dyscalculia, we may conclude that disturbance to pregnancy can lead to dyscalculia.  


We must keep in mind that simply being bad at math is not a symptom of dyscalculia. Knowing that more research needs to be done to learn what causes dyscalculia to occur, how can we diagnose a child with dyscalculia and on what base?  


Butterworth, B., (2018). Science of Dyscalculia. 1st ed. Routledge. https://doi.org/10.4324/9781315538112


Dyscalculia – Part III: The Arithmetic Network

"While the functioning of the grey matter and white matter is essential for a successful arithmetical connection to be made, the dyscalculic brain shows anomalies of structure and activation in the parietal lobes."
By 양미린 Mirin Yang, M.A.

Did you notice that there is an arithmetic network in our brain? Even before the advancement of modern neuroimaging, two major findings have been made clear through neurological patients who suffered from different brain injuries: frontal lobes are involved with unfamiliar calculations or problems and parietal lobes are related to the basic numerical processes 


Our frontal lobe is where everything begins; it is the region where we define tasks and goals when we face a new problem. The intraparietal sulci (IPS), which are bilaterally connected to the frontal lobe, are where the arithmetical network starts to operate. It is related to number abstraction, meaning it responds to the numbers no matter how it is presented (i.e. arrays of dots, digits, number words) and carries out simple calculation. Let’s imagine that you are given a problem 3 x 4. Without even thinking about the steps, you will answer 12 right away. Although you come up with the answer right away now, it must have taken a lot of effort and time when you just started to learn about the concept of multiplication.  


For most people, lots of practice are required to transit an unfamiliar problem into a known fact and our frontal lobes actively take the role in this stage. When the arithmetical fact is retrieved, the network now shifts to the parietal lobe. Specifically, the retrieval depends on a region called the angular gyrus which is just below the IPS. It was also found from research with children of 7-9 years old: children that can retrieve answers to single-digit addition problems used the hippocampus more than the children that still used basic counting skills to solve the problem (Butterworth, 2019). 


Then what about the dyscalculic brain? Although there is still much work to be done on this topic, some significant findings of the dyscalculic brain have been made: lower grey matter density in the left IPS and reduced white matter volume. The grey matter in the brain is where information processing occurs and the white matter delivers the processed information to different grey matter areas in our brain. While the functioning of the grey matter and white matter is essential for a successful arithmetical connection to be made, the dyscalculic brain shows anomalies of structure and activation in the parietal lobes.  

Butterworth (2019) suggests that further research on the dyscalculic brain, especially on how the different parts of the network are connected, will provide a deeper understanding of dyscalculia.  


I will end the article by throwing a question for all of us to consider – is there any way to construct an arithmetical network for dyscalculic children who have abnormalities in their brain structure through learning?   




Butterworth, B., (2018). The dyscalculic brain. Science of Dyscalculia. 1st ed. Routledge. https://doi.org/10.4324/9781315538112 

Dyscalculia – Part 2: Core deficit of the Number Module

"The number module refers to our innate ability of processing numerical information. When there is a core deficit in the number module, individuals develop dyscalculic traits."

By 김예경 Yekyung Kim, BSc

There are various causal factors in the development of dyscalculia, one of which is the deficiency of the number module. The number module refers to our innate ability of processing numerical information. When there is a core deficit in the number module, individuals develop dyscalculic traits. 

Dyscalculic individuals struggle with basic numerical operations. For instance, they struggle to understand that 4 is composed of four 1s or that addition and subtraction are inverse operations (e.g., 5 + 3 = 8, thus, 8 – 5 = 3). Such deficiency in processing numerical information could develop into everyday life difficulties.

For example, Samantha Abeel who reported having dyscalculia, said that she could not tell what time it was, calculate money in restaurants or supermarkets, nor understand distances. This made her feel anxious, resulting in sleeping problems. Thus, it is important for us to acknowledge that dyscalculia is a grave problem that needs to be addressed and researched further in order to support those in need of support. 

How do we know who has a core deficit in the number module? There are several ways for assessing the capacity of the number module, such as dot enumeration. During the dot enumeration task, participants are asked to count how many dots there are on the screen and their speed and accuracy are measured. 


Reeve et al. (2012) conducted a longitudinal study in Australia using dot enumeration, and found that children could be put into three groups depending on their performance. Children in the Slow group were only able to subitize up to two items, the Medium group were able to subitize three, and finally the Fast group could subitize up to four. Furthermore, the performance in dot enumeration predicted the arithmetic operations, such as subtraction and multiplication. The study suggests that dot enumeration allows early assessment of core deficit in the number module and the development of dyscalculia.  


How common is dyscalculia? Studies suggest that the prevalence rates of dyscalculia are around 3.5% to 7% of the population, due to the core deficit in the number module. In conclusion, dysfunctional number module is sufficient to cause a disability in processing numerical information. Although we have mainly focused on the cognitive basis of dyscalculia, other factors interact with the number module during the development of the disorder. For instance, what brain areas are responsible for the number module? Is dyscalculia heritable? We will answer these questions in the next articles.  

Butterworth, B., (2018). Core Deficit of Dyscalculia. Science of Dyscalculia. 1st ed. Routledge. https://doi.org/10.4324/9781315538112 

The function of Working Memory

"Though yet fully understood, what has been clarified is that our brain not only stores information simply in short and long term, but in the form of a working memory, where it could later be utilized for further processing."
By 전승혜 Seonghae Jeon, M.P.A.

Do “87 x 6” in your head. Most people would probably get the multiplication of 7 and 6 and at the same time store the number “4” on one side to later add it with the multiplication of 8 and 6. Just like this, our brain temporarily stores new information for further processing. This process requires approximately 3 subparts, phonological loops, visuo-spatial sketchpad, and central executive. 


The phonological loop stores 2 seconds worth of heard information. If we repeat and reinforce the heard information, it could be stored for longer than 2 seconds, but if not, its storage span is limited to approximately 2 seconds. What’s interesting is that the memory span is highly dependent on the vowel length and the speed of speech. English-speakers can recall 6.6 words in average within a given time. Welsh-speakers, who has comparatively longer vowels than English-speakers, are shown to recall less words, while Chinese-speakers were able to recall 9.9 words, given their shorter vowel lengths.


In a research on phonological loops, researchers concluded that children with larger phonological loops can recall more words than those with smaller ones, thus can learn reading and speaking at a faster rate. This also suggests that children with smaller phonological loops find reading and speaking difficult, so they are more likely to experience learning difficulties such as dyslexia.


Visuo-spatial sketchpad stores visual inputs. Our brain is known to better process visual stimulation than verbal stimulation. The sketchpad is an individual system to the phonological loop, which is why we can look at details of an art piece and have a conversation at the same time in an exhibition.  


Last but not least, the central executive analyzes and associates information taken in by the phonological loop and the visuo-spatial sketchpad. The role of the central executive is still under research. Though yet fully understood, what has been clarified is that our brain not only stores information simply in short and long term, but in the form of a working memory, where it could later be utilized for further processing


Sensory Memory

"Sensory memory refers to the temporary storage of information based on the stimuli we receive via our senses."
By 전승혜 Seonghae Jeon, M.P.A.

Sensory memory refers to the temporary storage of information based on the stimuli we receive via our senses. In other words, they are what we remember after seeing or hearing something. This process seems simple but is composed of multiple stages. First, our visual receptors see the object or characters in front of us, cause a chemical activity, start an electrical signal that reaches the neurons in the cortex of the brain. We call this process of the signal traveling from our eyes to the neurons in our brain sensory memory.


Let’s have a look at the image below.

Most people, without second thoughts, would identify the above image as ‘E’s. How do we perceive all of the characters above as ‘E’ when they all look so different?


For our brain to perceive a piece of information, it simplifies the task by analyzing what the eye sees by its component features. For example, there is a circular shape, a curve that starts from the left towards the right. After seeing the component features, our brain extracts information about the relationships between them and uses this information to identify the letter as an ‘E’ regardless of its exact size or orientation.


As such, our brain simplifies tasks into multiple steps rather than perceiving them as a whole. There are two main approaches in the process of perception, the bottom-up process, and the top-down process. The bottom-up process begins at the senses and continues in a linear fashion from one neuron to another, until information eventually arrives at the highest level of the cortex, while the top-down process is using information available at the higher levels to guide processing at lower levels. Let’s use the image below as an example.  

The second letters of both the first and second words look the same, but most people see them as an ‘H’ and an ‘A’ respectively. Just like that, our brain uses various approaches to perceive and make judgments about objects.


In a study, test subjects were given sentences that had words or letters taken away or changed and were tested on how they perceive the sentences. Surprisingly, 98% of the test subjects did not notice the change in the sentences.


It is common for us to see what we expect rather than to see what we are shown. We use the prior knowledge we store and (incorrectly) see objects, and even trick our brain that we are seeing what we expect to see.


The outcome of the perception is then stored in our brain as a visual image, later leading to short-term memory.


[Reference] Lieberman, D. A. (2012). Human learning and memory. Cambridge University Press.

Introduction to Memory

"Why do we forget things we used to memorize?"
By 전승혜 Seonghae Jeon, M.P.A.

We often interchangeably use the two concepts: memory and learning. The two concepts are intimately intertwined, but they are of fundamental difference. Learning focuses on the acquisition of knowledge or skill, whereas memory refers to our capacity to later recall it. Learning is the initial impact of an experience and memory is its subsequent effect.


Hermann Ebbinghaus is a German scholar who first conducted the very first experimental study of memory. He created and memorized nonsense syllables (meaningless material he would never have seen before) and read aloud the list, then immediately tried to repeat the list in the correct order until he reached a single perfect recitation. One major finding from this experiment was that practice was proven to be an important determinant governing memory. Memory depended not just on the frequency of practice, but also on how this practice was distributed over time. Recall proved to be better when the practice was distributed over multiple days. Ebbinghaus concluded that with sufficient practice, the material would effectively be remembered permanently, with no loss over time.


Q: Why do we forget things we used to memorize?


As the amount of practice on a list increased, the amount of forgetting fell off sharply. Forgetting was very rapid over the first hour but then declined only very gradually over subsequent days. In addition, memory can be retained for longer terms when there is an opportunity to review or refresh their memories at periodic intervals.



[Reference] Lieberman, D. A. (2012). Human learning and memory. Cambridge University Press.

Acquiring a Language through Body Movements and Story-telling

"If identical twins are found to be sufficiently more concordant than fraternal twins,
then there is a significant contribution of genetic factors."
By 전승혜 Seonghae Jeon, M.P.A.

Acquiring a language involves the entire process of listening, speaking, reading, and writing, and its purpose is to communicate with the other person in a seamless manner. In this process, children can be very active participants, and the Active Learners at Active Learning Center learn and acquire languages expressed in letters that seem challenging, sometimes through the body movement strategy, and sometimes through the story-telling strategy.


Children’s native tongues vary from Korean, English, to other languages. However, the language acquisition strategy learned by body movements or story-telling is one of the main learning strategies at our Active Learning Program developed based on psycho-educational clinical research for children who have difficulty in language development, and is proven to be very effective in acquiring their mother tongue or second language.

“Learning Disabilities” from the Perspective of Language Acquisition

"Children who have difficulty with visual processing face problems with visual discrimination, visual memory, or visual closure of letters and words."
By 전승혜 Seonghae Jeon, M.P.A.

According to many academic studies, learning disorders in young children can be expressed in various forms. It is said that in the learning situation where visual and auditory skills are used, one might wonder if a child is suffering from a learning disability.


Children who have difficulty with visual processing face problems with visual discrimination, visual memory, or visual closure of letters and words. Young children’s visual processing and subsequent spelling problems are considered one of the early signs of learning disorders and pose the risk of leading to reading disorders. On the other hand, children who have difficulty with auditory processing have problems with speech recognition, auditory discrimination, auditory memory, and auditory arrangement and mixing. For children who start learning to read, the listed difficulty can pose a potential threat to reading as a whole.

Much of the learning depends on whether the language has been well acquired, and for young children, language acquisition plays a vital role in developing the ability to think and understand abstract concepts during the development process. According to researchers, language acquisition problems with which were not dealt at an early age can cause bigger problems.


The usual cases in which one can doubt whether a child is experiencing language-related learning problems include if the child speaks too little or not at all at a certain age, or has difficulty using grammar or syntax correctly, a significantly lower vocabulary related to learning, and a low understanding of verbal language. The psychological and psycho-educational approach at our “Active Learning Center” is delicately addressed based on such academic theory.

Special Lecture on “Bilingual Children” by Dr. Cho

"What can be called bilingual does not depend on whether you can speak both languages perfectly, but on whether you can communicate with others in both languages in daily life."
By 전승혜 Seonghae Jeon, M.P.A.

On the last Friday evening of February at the “Active Learning Center,” Dr. Cho Yong-beom, the head of Dutree Group, gave a special lecture on “Brilliant Children.” It’s time to explore in depth what challenges bilingual children can face learning, psychological, emotional and social, how to overcome, and what benefits they can have in the process of growing up.


Bilingual children are known to have the following advantages:

– Less prescriptive / more creative / more flexible and open to new ideas
– “Distributive thinking” in problem-solving – having the ability to find various, possible, and non-pessimistic solutions to a problem
– Two or more expressive(language) systems foster flexibility and creativity of thinking
– Looking at language as a single object (“meta-language recognition”), able to understand the arbitrary nature of words
– Have a rich sense of communication
– “Additional Antenna” – respond more sensitively to surroundings, pay more careful attention to conversations, and capture both verbal and non-verbal queues more delicately


What can be called bilingual does not depend on whether you can speak both languages perfectly, but on whether you can communicate with others in both languages in daily life. Thus, it is natural that bilingual abilities develop disproportionately according to the individual’s environment. A bilingual child can become either “Bilingual Additif” (when the child develops two languages equally and this experience of language development helps with subsequent cognitive development) or “Bilingual Sustractif” (when the child develops a second language at the expense of his or her native language).


It is often assumed that bilingual children are at a disadvantage, experiencing mental confusion when two languages are mixed up in their minds. However, according to academic research on brain observation, young children have overlapping regions of the brain that govern both languages, treating them as if they are a single language. All of our “Active Learning Center” clinicians use this academic and empirical knowledge to provide professional service to all of our children.

Learn to multiply and divide through Visualization

"The "Active Learners" at our Active Learning Center learn the mathematical concepts and principles to do multiplication and division through visualization strategy."
By 전승혜 Seonghae Jeon, M.P.A.

The “Active Learners” at our Active Learning Center learn the mathematical concepts and principles to do multiplication and division through visualization strategy. It helps improve mathematical thinking ability as children visually experience toys becoming numbers, and vice versa.


Visualization is one of our major academic strategies that our Active Learning program is implementing to help children who especially struggle with learning math effectively. This strategy was developed based on our clinical and psycho-educational researches and approaches.

Additionally, our Active Learners utilize not only the visualization strategy, but also their personal experiences and simplified story-telling skills to solve math problems, especially word problems, which at first seemed challenging. Please continue posted with our notices to find more about the story-telling skills!