“Doctor, I’m Having Trouble Reading” – Part 4


Ruth has two concurrent problems, the first and more obvious one involving her inability to identify letters despite being able to write them, and the secondary issue of her right visual field defect.  The first step in rehabilitation would be to enable her to recognize letters and then words.  The second would be to help her track into her right field with more accuracy.

Ruth had one major advantage over other patients experiencing alexia sine agraphia: As a former schoolteacher she was experienced in helping young children learn to read.  She therefore put herself in the mindset of a child learning alphabet letters for the first time.  Initially she would point to the letter and draw it in the air.  She used her intact object recognition and naming skills to link the look of familiar objects with the first letter of the word.

Once Ruth had a better command of identifying individual letters, evidenced by her improved verbal reading of the Snellen Chart, we built her ability to blend words visually using the phonetic focus procedure.  Ruth then faced the next hurdle in being able to visually scan across a line in the presence of her right sided field defect.  This difficulty is what many authors refer to as hemianopic dyslexia.  The figure that you see here is a representation of the normal parafoveal preview that readers of English utilize.  The ability to be able to take in a window to the right of fixation is crucial in driving saccades along the line proceeding from left to right.  The figure is contained in a wonderful review paper:  Schuett  S, Heywood C A, Kentridge RW, Zihl J. The significance of visual information processing in reading: insights from hemianopic dyslexia.  Neuropsychologia 2008; 46:2445–2462.

For this reason, the ideal procedure for Ruth to master is Michigan Letter Tracking (MLT).  In the beginning phases Ruth needed only to keep track of the letters by circling them in alphabetic sequence.  We then want her to say the alphabet letters as she circles them to reinforce letter naming ability.  As she picks up speed in doing this, she is becoming more skilled in Rapid Automatized Naming (RAN).  She then proceeded to Michigan Word Tracking.  Take a look at Ruth’s body position as she performs MLT, proceeding along the line from left to right.  She starts out fine in her unrestricted field on the left side, but as she tracks to the right she has to re-position herself to double-check that she hasn’t missed something toward the right margin.

2 thoughts on ““Doctor, I’m Having Trouble Reading” – Part 4

  1. So we are not going to try yolked prisms? In addition, we are not going to try a book mark
    at the left of the page?
    So in an infant, the visual cortex is all visual at out the distance to mom’s face, then this visual gives way to Langage on only the left side of the brain? This must be true, since
    Ruth would still have reading ability if there is a duplicate on the right side of the brain
    August

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