 Pure , or phonologically @-@ based , dyslexia , also known as <unk> dyslexia , dyslexia without <unk> , and pure word blindness , is dyslexia due to difficulty in recognizing written sequences of letters ( such as words ) , or sometimes even letters . It is considered ' " pure " because it is not accompanied by other significant language @-@ related impairments . Pure dyslexia does not affect speech , handwriting style , language or comprehension impairments . Pure dyslexia is caused by lesions on the visual word form area ( VWFA ) . The VWFA is composed of the left lateral occipital sulcus and is activated during reading . A lesion in the VWFA stops transmission between the visual cortex and the left angular gyrus . It can also be caused by a lesion involving the left occipital lobe or the <unk> . It is usually accompanied by a homonymous hemianopsia in the right side of the visual field . Multiple oral re @-@ reading ( MOR ) is a treatment for pure dyslexia . It is considered a top @-@ down processing technique in which affected individuals read and reread texts a predetermined number of times or until reading speed or accuracy improves a predetermined amount . 
