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.