Visual vector inversion in the posterior parietal cortex.
In the antisaccade task, a saccade must be triggered towards the mirror location of a visual target. The neural basis required for this visual vector inversion remains unclear, although neuronal activities reflecting this process have been recorded in the monkey lateral intraparietal area. We examined a patient with a small, right-sided, posterior parietal stroke who complained of difficulty in manipulating visual information. Antisaccades were markedly hypometric rightwards but normal leftwards. Largely unaffected performances in other saccade tasks revealed that visual and motor processing were not significantly affected. Antisaccade inaccuracy could therefore be ascribed to the impairment of visual vector inversion, a processing specifically required in this task. These findings provide the first evidence in humans that visual vector inversion could be an intrinsic property of the posterior parietal cortex.
Nyffeler
Thomas
T
National Institute of Health and Medical Research, Pitie-Salpetriere Hospital, Paris, France.
Rivaud-Pechoux
Sophie
S
Pierrot-Deseilligny
Charles
C
Diallo
Ramata
R
Gaymard
Bertrand
B
D000328:Adult; D005133:Eye Movements / Q000502:physiology; D005260:Female; D007839:Functional Laterality / Q000502:physiology; D006801:Humans; D007092:Imagination / Q000502:physiology; D008279:Magnetic Resonance Imaging; D008297:Male; D008568:Memory / Q000502:physiology; D008875:Middle Aged; D010296:Parietal Lobe / Q000503:physiopathology*; D010775:Photic Stimulation; D011597:Psychomotor Performance / Q000502:physiology; D012438:Saccades / Q000502:physiology; D020521:Stroke / Q000503:physiopathology*; D014796:Visual Perception / Q000502:physiology*