Line bisection following hemispherectomy.
Two left- and right-hemispherectomized patients with contralateral hemianopia and 20 normal controls were administered a line bisection task. All hemispherectomized patients showed a strong bisection bias towards their blind visual field. This contralateral bias persisted when patients were forced to start scanning within their blind hemifield, supporting the idea of a strategic adaptation of attention towards the blind visual field. In all patients the hemispherectomy was performed as a result of cortical abnormality (congenital or acquired) and therefore early changes in functional cerebral organization may have occurred in these patients. The absence of a neglect-like ipsilateral bias and the presence of a hemianopic-like contralateral bias in line may represent a functional deficit or suggest that plastic changes following hemispherectomy induced an adaptive functional re-organization of spatial attention in both left- and right-hemispherectomized patients.
Hausmann
Markus
M
Department of Psychology, University of Auckland, Auckland, New Zealand. markus.hausmann@ruhr-uni-bochum.de
Waldie
Karen E
KE
Allison
Stephanie D
SD
Corballis
Michael C
MC
D000222:Adaptation, Physiological / Q000502:physiology; D000328:Adult; D001288:Attention / Q000502:physiology; D001925:Brain Damage, Chronic / Q000503:physiopathology*; D005260:Female; D007839:Functional Laterality / Q000502:physiology*; D038421:Hemispherectomy; D006801:Humans; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D009949:Orientation / Q000502:physiology; D010364:Pattern Recognition, Visual / Q000502:physiology; D010468:Perceptual Disorders / Q000503:physiopathology*; D011597:Psychomotor Performance / Q000502:physiology*; D013037:Spatial Behavior / Q000502:physiology; D014794:Visual Fields / Q000502:physiology*