Visuomotor system uses target features unavailable to conscious awareness.
After lesions to primary visual cortex, patients lack conscious awareness of visual stimuli. Interestingly, however, some retain the ability to make accurate judgments about the visual world (i.e., so-called blindsight). Similarly, damage to inferior occipitotemporal regions of cortex (e.g., lateral occipital cortex) can result in an inability to perceive object properties while retaining the ability to act on them (i.e., visual form agnosia). In the present work, we demonstrate that the ability to interact with objects in the absence of conscious awareness is not isolated to those with restricted neuropathologic conditions. Specifically, neurologically intact individuals are able to program and execute goal-directed reaching movements to a target object without awareness of extrinsic target properties; they accurately tune the dynamics of their movement and modulate it online without conscious access to features of the goal object. Thus, the planning and execution of actions are not dependent on conscious awareness of the environment, suggesting that the phenomenon of blindsight (and agnosia) reflect normal conditions of the visual system.
Binsted
Gordon
G
College of Kinesiology, Neural Systems and Plasticity Research Group, University of Saskatchewan, Saskatoon, SK, Canada. gordon.binsted@ubc.ca
Brownell
Kyle
K
Vorontsova
Zofia
Z
Heath
Matthew
M
Saucier
Deborah
D
D000328:Adult; D001364:Awareness / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D014785:Vision, Ocular / Q000502:physiology*