Specific Learning Disorders

'Specific Learning Disorder', or SLD, is an umbrella term which includes impairment in reading, writing or maths, or a combination of the three.   The term 'dyslexia' is sometimes used to describe an SLD in reading and spelling, and 'dyscalculia' refers to an SLD in maths.   Dysgraphia, a less commonly heard term, refers to difficulty with written expression.

Certain cognitive processing abilities are often impaired in individuals with SLD.  In the case of dyslexia, phonological processing (the ability to differentiate the sounds we use for speech) is commonly affected, which in turn affects orthographic knowledge (the ability to link speech sounds to specific letters).  Working memory and processing speed may also be affected.

SLDs are best thought of as existing on a continuum, which can range from mild to severe, as there is no clear-cut demarcation or definitive diagnosis.  Instead, a number of factors are considered when making a judgement as to the presence of an SLD.

For a diagnosis to be made, a number of criteria must be met.  For example, a key aspect of the disorder, which research suggests has a neurological basis, is that the academic difficulty is unexpected.  This means that academic achievement is markedly below what would be predicted when compared to the individual's general cognitive or oral language abilities (such as vocabulary knowledge, language comprehension and reasoning proficiency).  Indeed, it is not uncommon for those afflicted to have average or higher general intelligence. Secondly, as the name suggests, the impairment is specific to a particular academic area or areas, rather than a more generalised academic difficulty.      

 A diagnosis of SLD must also rule out the probability of other causative factors, such as intellectual disability, vision or hearing impairment, neurological or motor disorder, gaps in schooling, lack of familiarity with English, or social disadvantage.  

In a nutshell, people with SLDs generally have average or above intelligence, but struggle with the written word, or with understanding numbers.   Untreated, the effects can be far reaching.  Research points to a number of possible lifelong consequences, including lower rates of post-secondary education, higher rates of unemployment and under-employment, lower incomes, higher levels of psychological distress and poorer overall mental health.  Targeted intervention and support, however, can significantly improve learning outcomes, and substantially lessen other, less direct, effects.  

The first step in providing needed academic and emotional support is to establish whether or not the learning difficulty is in fact the result of an SLD.

What are the common symptoms of SLDs?

What does a diagnostic assessment involve?