Can spatial and temporal motion integration compensate for deficits in local motion mechanisms?
We studied the motion perception of a patient, AMG, who had a lesion in the left occipital lobe centered on visual areas V3 and V3A, with involvement of underlying white matter. As shown by a variety of psychophysical tests involving her perception of motion, the patient was impaired at motion discriminations that involved the detection of small displacements of random-dot displays, including local speed discrimination. However, she was unimpaired on tests that required spatial and temporal integration of moving displays, such as motion coherence. The results indicate that she had a specific impairment of the computation of local but not global motion and that she could not integrate motion information across different spatial scales. Such a specific impairment has not been reported before.
Vaina
Lucia M
LM
Brain and Vision Research Laboratory, Biomedical Engineering and Neurology, Boston University, Boston, MA, USA. vaina@engc.bu.edu
Gryzwacz
Norberto M
NM
Saiviroonporn
Pairash
P
LeMay
Marjorie
M
Bienfang
Don C
DC
Cowey
Alan
A
D001931:Brain Mapping; D016022:Case-Control Studies; D003118:Color Perception; D015350:Contrast Sensitivity; D003867:Depth Perception; D005260:Female; D007839:Functional Laterality; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D009039:Motion Perception / Q000502:physiology*; D009778:Occipital Lobe / Q000033:anatomy & histology / Q000503:physiopathology*; D010468:Perceptual Disorders / Q000503:physiopathology; D011601:Psychophysics; D013028:Space Perception / Q000502:physiology*; D020521:Stroke / Q000503:physiopathology*; D014794:Visual Fields