A Computational Model of Spatial Representations that Explains Object-Centered Neglect in Parietal Patients

  • Rajesh P. N. Rao
  • Dana H. Ballard


Patients with parietal cortex lesions exhibit unusual visual deficits, typically involving the neglect of a part of their visual space. Without being consciously aware of it, they act as if that part of space is not visible. At first, it was thought that this neglected space coincided with the visual hemifield contralateral to the lesioned hemisphere, but more recently, an increasing number of experiments [1, 2, 5, 6, 7, 8, 11] have shown that in many cases, the neglected part of space is related to a reference object of immediate interest. For example, in a recent experiment by Behrmann et al. [3], a patient with a right parietal lobe lesion was asked to count the number of instances of the letter “A” in a field of letters on a TV screen (see Figure 1). The eye movements recorded from the subjects showed that they typically neglected to look at most of the “A”s in the left side of the TV screen. Note that the neglect cannot be explained as a visual hemifield neglect because, as the patient makes eye movements, the letters that appear in each hemifield change.


Parietal Cortex Spatial Representation Iconic Representation Unilateral Neglect Contralesional Side 
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Copyright information

© Springer Science+Business Media New York 1997

Authors and Affiliations

  1. 1.Department of Computer ScienceUniversity of RochesterRochesterUSA

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