children), ﬂuent word decoding, spelling, or math facts; reading aloud is slow, inaccurate, and effortful, and some children struggle to understand the magnitude that a spoken or written number represents. Children in primary grades (grades 1—3) may continue to have problems recognizing and manipulating phonemes, be unable to read common one-sylla- ble words (such as mat or top), and be unable recognize common irregularly spelled words (e.g., said, two). They may commit reading errors that indicate problems in con- necting sounds and letters (e.g., ”big” for "got”) and have difficulty sequencing numbers and letters. Children in grades 1-3 also may have difficulty remembering number facts or arithmetic procedures for adding, subtracting, and so forth, and may complain that read- ing or arithmetic is hard and avoid doing it. Children with specific learning disorder in the middle grades (grades 4—6) may rnispronounce or skip parts of long, multisyllable words (e.g., say ”conible” for ”convertible,” ”aminal” for ”animal”) and confuse words that sound alike (e.g., ”tornado” for ”volcano”). They may have trouble remembering dates, names, and telephone numbers and may have trouble completing homework or tests on time. Children in the middle grades also may have poor comprehension with or without slow, effortful, and inaccurate reading, and they may have trouble reading small function words (e.g., that, the, an, in). They may have very poor spelling and poor written work.
They may get the first part of a word correctly, then guess wildly (e.g., read ”clover” as ”clock”), and may express fear of reading aloud or refuse to read aloud.
By contrast, adolescents may have mastered word decoding, but reading remains slow and effortful, and they are likely to show marked problems in reading comprehension and written expression (including poor spelling) and poor mastery of math facts or mathemat- ical problem solving. During adolescence and into adulthood, individuals with specific learning disorder may continue to make numerous spelling mistakes and read single words and connected text slowly and with much effort, with trouble pronouncing multi- syllable words. They may frequently need to reread material to understand or get the main point and have trouble making inferences from written text. Adolescents and adults may avoid activities that demand reading or arithmetic (reading for pleasure, reading instruc- tions). Adults with specific learning disorder have ongoing spelling problems, slow and effortful reading, or problems making important inferences from numerical information in work-related written documents. They may avoid both leisure and work-related activ- ities that demand reading or writing or use alternative approaches to access print (e.g., text-to-speech/speech-to-text software, audiobooks, audiovisual media).
An alternative clinical expression is that of circumscribed learning difficulties that per- sist across the lifespan, such as an inability to master the basic sense of number (e.g., to know which of a pair of numbers or dots represents the larger magnitude), or lack of pro— ficiency in word identification or spelling. Avoidance of or reluctance to engage in activi— ties requiring academic skills is common in children, adolescents, and adults. Episodes of severe anxiety or anxiety disorders, including somatic complaints or panic attacks, are common across the lifespan and accompany both the circumscribed and the broader ex- pression of learning difficulties.
Environmental. Prematurity or very low birth weight increases the risk for specific learning disorder, as does prenatal exposure to nicotine.
Genetic and physiological. Specific learning disorder appears to aggregate in families, particularly when affecting reading, mathematics, and spelling. The relative risk of spe- cific learning disorder in reading or mathematics is substantially higher (e.g., 4—8 times and 5—10 times higher, respectively) in first-degree relatives of individuals with these learning difficulties compared with those without them. Family history of reading diffi- disorder in offspring, indicating the combined role of genetic and environmental factors.