Pointing to two imaginary targets at the same time: Bimanual allocentric and egocentric localization in visual form agnosic DF

NEUROPSYCHOLOGIA

卷:47

Article

Carey, David P.¹  Dijkerman, H. Chris²  Milner, A. David³ 

[1] Univ Aberdeen, Sch Psychol, Vis Res Labs, Aberdeen AB24 2UB, Scotland

[2] Univ Utrecht, Helmholtz Res Inst, NL-3584 CS Utrecht, Netherlands

[3] Univ Durham, Wolfson Res Inst, Stockton On Tees TS17 6BH, England

关键词: Visual form agnosia;    Two visual systems;    Bimanual aiming;    Spatial processing: allocentric;    Egocentric;   

DOI  :  10.1016/j.neuropsychologia.2009.02.001

来源: Elsevier

【 摘 要 】

We have previously shown the visual form agnosic patient D.F. has spared sensorimotor utilization of visual information relative to her poor perceptual processing of the same stimulus attributes. Her visuomotor skills are, however, only normal when egocentric visual coding can be used in the task. In other words, her egocentric sensorimotor processing is intact while her 'allocentric' coding of spatial position is impaired. The current investigation extends these previous observations by Comparing D.F.'s performance in bimanual pointing to pairs of stimuli directly (the egocentric task) versus pointing to the homologous positions on an adjacent workspace (pantomimed reaching, the allocentric task). The results showed greatly superior pointing accuracy in direct pointing compared to pantomimed pointing. The mechanisms supporting her limited but remaining sensitivity to spatial relationships during pantomimed pointing remain unknown. These residual skills may reflect partially spared categorical coding and/or internal sensorimotor self-cueing. Crown Copyright (C) 2009 Published by Elsevier Ltd. All rights reserved.

【 授权许可】

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