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Updated: Jul 15, 2026
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A Large Lateral Craniotomy Procedure for Mesoscale Wide-field Optical Imaging of Brain Activity
Published on: May 7, 2017
No representation without awareness in the lateral occipital cortex.
Thomas A Carlson1, Robert Rauschenberger, Frans A J Verstraten
1Department of Psychology, Harvard University, 33 Kirkland Street, Cambridge, MA 02138, USA. tom@wjh.harvard.edu
Psychological Science
|May 2, 2007
Summary
Masking stimuli, like four trailing dots, can eliminate conscious awareness of a target. Neuroimaging reveals no lingering brain activity for masked stimuli, ruling out simple inaccessibility.
Area of Science:
- Cognitive Neuroscience
- Visual Perception
Background:
- Masking stimuli can prevent conscious awareness of visual targets.
- Previous theories proposed neural representations might persist but be inaccessible.
Purpose of the Study:
- To investigate the neural basis of visual masking.
- To determine if masked stimuli leave a persistent neural trace.
Main Methods:
- Functional magnetic resonance adaptation (fMRA) was employed.
- Researchers examined activity in the lateral occipital cortex.
Main Results:
- No persistent neural representation was found for successfully masked stimuli.
- Activity in the lateral occipital cortex, crucial for object structure, was absent.
Conclusions:
- Successfully masked stimuli are not merely inaccessible but are eliminated from neural processing.
- This challenges theories suggesting lingering, but unconscious, neural representations.
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