ABSTRACT
Studies of visual processes involved in skilled reading have frequently assessed the effects of visual format on word identification. The authors report two experiments. In Experiment 1, they document the reading of three patients, two with damage to parietal cortex (G. K. and F. L.) and one with damage to the ventral occipital cortex (H. J. A.). The parietal patients were severely impaired at identifying words in mixed compared with lowercase, but showed no greater effects of contrast reduction than control participants. The occipital patient, however, showed a much less marked effect of case mixing while manifesting a strong effect of contrast reduction. In Experiment 2, the authors report converging evidence from the effects of transcranial magnetic stimulation (TMS) applied to parietal and occipital cortex of normal readers. In the case experiment, the words were presented in high or low contrast, either in single or mixed case. G. K. presented a number of neuropsychological problems including: Balint's syndrome, left neglect and extinction and attentional dyslexia.
