EYE-MOVEMENT PATTERNS IN READING AS A FUNCTION OF VISUAL-FIELD DEFECTS AND CONTRAST SENSITIVITY LOSS

Saccadic eye movements during reading were examined as a function of t he side of visual field cut and the impairment of visual contrast sens itivity. Five patients with various visual field defects were compared to five age-matched controls. Patients with right visual field defect showed an increase in the number of rightward saccades and a decrease in their amplitude, and patients with left visual field defects showe d a pattern more similar to that of the control subjects, Two patients showed a selective deficit in the range of medium-high spatial freque ncy; they were the only patients to show a lengthening of mean fixatio n time during reading. These results indicate selective effects on rea ding depending on primary sensory defects. The clinical relevance of t hese findings is briefly discussed.