Impairment in reading
The problems with reading are likely to be related to processes and skills involved in fluent and accurate reading. Pullen and Cash succinctly define reading as 'a process of constructing meaning from print' involving 'decoding' and 'comprehension'. The manual DSM-5 (American Psychiatric Association) proposes an overarching category of 'specific learning disorder' which may involve combinations of impairment in reading, written expression or mathematics. Estimating the prevalence of impairment in reading is difficult because it and its related terms are defined and operationalised in different ways. While reading disability has a genetic component, genetic knowledge cannot presently inform differential identification or individualised types of intervention. As Elliott and Grigorenko recognise, there is 'limited knowledge and understanding of the role genetic factors play in reading development'. Widely researched factors are phonological processing, auditory and visual processing, rapid naming, short-term and working memory, and attention.