|
Dysgraphia is a deficiency in the ability to write, primarily in terms of handwriting, but also in terms of coherence.〔Chivers, M. (1991). "Definition of Dysgraphia (Handwriting Difficulty). ''Dyslexia A2Z''. Retrieved from http://www.dyslexiaa2z.com/learning_difficulties/dysgraphia/dysgraphia_definition.html〕 Dysgraphia is a transcription disability, meaning that it is a writing disorder associated with impaired handwriting, orthographic coding (orthography, the storing process of written words and processing the letters in those words), and finger sequencing (the movement of muscles required to write). It often overlaps with other learning disabilities such as speech impairment, attention deficit disorder, or developmental coordination disorder. In the ''Diagnostic and Statistical Manual of Mental Disorders'' (DSM-IV), dysgraphia is characterized as a learning disability in the category of written expression when one’s writing skills are below those expected given a person’s age measured through intelligence and age appropriate education. The DSM is not clear in whether or not writing refers only to the motor skills involved in writing, or if it also includes orthographic skills and spelling.〔 The word dysgraphia comes from the Greek words ''dys'' meaning "impaired" and ''graphia'' meaning "writing by hand".〔 There are at least two stages in the act of writing: the linguistic and the motor-expressive-praxic stage. The linguistic stage involves the encoding of auditory and visual information into symbols for letters and written words. This is mediated through the angular gyrus, which provides the linguistic rules which guide writing. The motor stage is where the expression of written words or graphemes is articulated. This stage is mediated by Exner’s writing area of the frontal lobe. People with dysgraphia can often write on some level and may experience difficulty with other fine motor skills, such as tying shoes. However, dysgraphia does not affect all fine motor skills. People with dysgraphia often have unusual difficulty with handwriting and spelling〔 which in turn can cause writing fatigue.〔 They may lack basic grammar and spelling skills (for example, having difficulties with the letters p, q, b, and d), and often will write the wrong word when trying to formulate their thoughts on paper. The disorder generally emerges when the child is first introduced to writing.〔 Adults, teenagers, and children alike are all subject to dysgraphia.〔NCLD Editorial Staff. (2010). "What is Dysgraphia?" ''National Center for Learning Disabilities''. Retrieved from http://www.ncld.org/ld-basics/ld-aamp-language/writing/dysgraphia.〕 Dysgraphia should be distinguished from agraphia, which is an acquired ''loss'' of the ability to write resulting from brain injury, stroke, or progressive illness.〔(【引用サイトリンク】 title=agraphia )〕 ==Classification== Dysgraphia is often, but not always, accompanied by other learning differences such as dyslexia or attention deficit disorder,〔 and this can impact the type of dysgraphia a person might have. There are three principal subtypes of dysgraphia that are recognized. There is little information available about different types of dysgraphia and there are likely more subtypes than the ones listed below. Some children may have a combination of two or more of these, and individual symptoms may vary in presentation from what is described here. Most common presentation is a motor dysgraphia/agraphia resulting from damage to some part of the motor cortex in the parietal lobes. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Dysgraphia」の詳細全文を読む スポンサード リンク
|