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Motor role of human inferior parietal lobe revealed in unilateral neglect patients

Naturevolume 392pages179182 (1998) | Download Citation



The exact role of the parietal lobe in spatial cognition is controversial. One influential hypothesis proposes that it subserves spatial perception1, whereas other accounts suggest that its primary role is to direct spatial movement2,3. For humans, it has been suggested that these functions may be divided between inferior and superior parietal lobes, respectively2,4. In apparent support of a purely perceptual function for the inferior parietal lobe (IPL), patients with lesions to this structure, particularly in the right hemisphere, exhibit unilateral spatial neglect (deficient awareness for the side of space opposite to that of their lesion)5. Here we show that patients with right IPL lesions also have a specific difficulty in initiating leftward movements towards visual targets on the left side of space. This motor impairment was not found in neglect patients with frontal lesions, contrary to previous proposals that motor aspects of neglect are particularly associated with anterior damage6,7,8,9. Our results suggest that the human IPL operates as a sensorimotor interface, rather than subserving only perceptual functions.

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We thank J. Wade and A. Rudd, and the staff and patients of the stroke units at Charing Cross Hospital and St. Thomas' Hospital, London. This research was supported by the Stroke Association and the Wellcome Trust. J.B.M. was supported by a National Health and Medical Research Council (Australia) Neil Hamilton Fairley Fellowship, and by AMRAD Australia.

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  1. Department of Experimental Psychology, University of Cambridge, CB2 3EB, Cambridge, UK

    • Jason B. Mattingley
  2. Division of Neuroscience and Psychological Medicine, Imperial College School of Medicine, Charing Cross Hospital, W6 8RF, London, UK

    • Masud Husain
    •  & Christopher Kennard
  3. Department of Psychology, Institute of Cognitive Neuroscience, University College London, Gower Street, WC1E 6BT, London, UK

    • Chris Rorden
    •  & Jon Driver


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Correspondence to Masud Husain.

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