Developmental dyslexia is a condition or learning disability which causes difficulty with reading and writing. Its standard definition is a difficulty in reading and writing in spite of normal development of intelligence, cognitive and sensory abilities.

People are often identified as dyslexic when their reading or writing problems cannot be explained by a lack of intellectual ability, inadequate instruction, or sensory problems such as poor eyesight.

Some disagreement exists as to whether dyslexia does indeed exist as a condition, or whether it simply reflects individual differences among different readers..

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