Learning to read and write are complex processes, which can be disrupted in various ways, leading to disorders known as dyslexia（难语症，阅读障碍） and dysgraphia（书写障碍） . Two new studies, published in a recent special issue of Elsevier's Cortex (http://www.sciencedirect.com/science/journal/00109452) provide evidence of this variety, suggesting that effective treatment needs to take it into account. A group of researchers from the Universities of Bari and Rome in Italy studied the reading and writing abilities of 33 Italian dyslexic（诵读困难的） children, comparing their performance with that of children with normal reading ability. Italian is an "orthographically transparent" language, meaning that letters tend to correspond to the same sounds, whereas many letters in the English alphabet change their sound from word to word (like the "c" in car and city). However, the new study showed that even in Italian, in which it is relatively straightforward（简单的，坦率的） to convert sounds into letters, children still have difficulties in spelling. Younger children with dyslexia generally performed worse than proficient（熟练的，精通的） readers; however, the older ones showed a more selective impairment when spelling words, suggesting that knowledge of vocabulary may be more important in spelling than previously thought.

The other study, from Tel Aviv University, Israel, provided the first systematic description of a type of reading disorder called "attentional dyslexia" in which children identify letters correctly, but the letters jump between words on the page, e.g., "kind wing" is read as "wind king". Teachers and neuropsychologists often notice that children substitute（代替） letters when reading, but in this type of dyslexia the substitutions are not caused by inability to identify letters or convert them to sounds; they result from migrations of letters between words. The findings showed that letters would mostly migrate to the same position in another word, so the first letter of one word would switch places with the first letter of another word. Awareness to the existence of this type of dyslexia is important, because it suggests a straightforward way to assist these children in reading - by presenting a ‎single word at a time, e.g., with the help of a word-sized window cut in a piece of cardboard（硬纸板） .