 Pure, or phonologically-based, dyslexia, also known as agnosic dyslexia, dyslexia without agraphia, 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 splenium. 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.
