Is "ambient vision" distributed in the brain? Effects of wide-field-view visual yaw motion on PET activation.
Ambient vision comprises the visual functions that are associated with the maintenance of spatial orientation and that depend on peripheral, preconscious visual inputs. Although a limited number of brain areas appear to be activated by coherent wide-field-of-view (WFOV) motion in more than one axis, a diffuse pattern of lateralized brain activity occurs in response to clockwise or counterclockwise ambient visual roll motion. In the present study involving positron emission tomography (PET), a similar finding was shown for rightward versus leftward yaw stimulation. A total of 18 PET scans were obtained from six subjects in response to either leftward or rightward WFOV motion in a collimated display subtending > 100 degrees horizontally. Rightward stimulation elicited mainly activation throughout the right hemisphere, whereas leftward stimulation elicited mainly activation throughout the left hemisphere. These findings provide further evidence that the ambient vision signal is either processed or transmitted throughout the entire brain, as befits a visual function that is fundamental to all other perceptual systems.
Previc
F H
FH
Flight Motion Effects Branch, Air Force Research Laboratory, Brooks Air Force Base, Texas, USA. fred.previc@brooks.af.mil
Beer
J
J
Liotti
M
M
Blakemore
C
C
Fox
P
P
D000328:Adult; D001921:Brain / Q000000981:diagnostic imaging; D004292:Dominance, Cerebral; D005260:Female; D007839:Functional Laterality; D006801:Humans; D008297:Male; D008875:Middle Aged; D009039:Motion Perception / Q000502:physiology*; D009949:Orientation / Q000502:physiology*; D013028:Space Perception / Q000502:physiology*; D014055:Tomography, Emission-Computed; D014794:Visual Fields / Q000502:physiology*