The sightless view: neural correlates of occluded objects.
The relationship between neural activity and object perception has received considerable attention using stimulus manipulations such as masking or dichoptic presentation. Here we investigate the same problem by occluding objects with an opaque screen that acts to dissociate the direct perception of the object from the awareness of its presence. We used functional magnetic resonance imaging to measure brain activity when subjects viewed objects (faces and houses) that underwent occlusion and found that the response of the majority of the fusiform face area (FFA) and lateral occipital cortex is the same whether the object is visible or occluded. This suggests that when objects are directly viewed, activity within object-selective regions may reflect the awareness of presence, not the direct perception, of the object. Additionally, we identify a region of premotor cortex that is selectively activated by occlusion of either object type, suggesting its generic involvement with processing occluded objects.
Hulme
Oliver J
OJ
Anatomy Department, Wellcome Department of Imaging Neuroscience, University College London, London WC1E6BT, UK. o.hulme@ucl.ac.uk
Zeki
S
S
D000328:Adult; D001931:Brain Mapping; D005074:Evoked Potentials, Visual / Q000502:physiology*; D005145:Face; D005260:Female; D006801:Humans; D008297:Male; D009778:Occipital Lobe / Q000502:physiology*; D010364:Pattern Recognition, Visual / Q000502:physiology*; D010470:Perceptual Masking / Q000502:physiology*; D013647:Task Performance and Analysis; D014793:Visual Cortex / Q000502:physiology*