Abnormal Attentional Modulation of Retinotopic Cortex in Parietal Patients with Spatial Neglect

摘要: Brain regions beyond visual cortex are thought to be responsible for attention-related modulation of processing [1, 2], but most evidence is indirect. Here, we applied functional magnetic resonance imaging (fMRI), including retinotopic mapping areas, patients with focal right-parietal lesions and left spatial neglect [3, 4]. When attentional load at fixation was minimal, areas in right showed preserved responses task-irrelevant checkerboards the contralateral hemifield, analogously right-hemifield checkerboards, indicating a "symmetric" pattern both hemispheres respect stimulation under these conditions. But when increased, asymmetry emerged cortex, being pathologically reduced (even eliminated V4/TEO), whereas no such reduction their response. These results reveal attention-dependent abnormalities after distant (parietal) regions. This may explain otherwise puzzling aspects [5, 6], as confirmed here by additional behavioral testing.