Title
The neural substrates of conscious color perception demonstrated using fMRI.
Abstract
It is well established that seeing color activates the ventral occipital cortex, including the fusiform and lingual gyri, but less is known about whether the region directly relates to conscious color perception. We investigated the neural correlates of conscious color perception in the ventral occipital cortex. To vary conscious color perception with the stimuli-remaining constant, we took advantage of the McCollough effect, an illusory color effect that is contingent on the orientation of grating stimuli. Subjects were exposed to a specific combination of chromatic grating patterns for 10 min to induce the McCollough effect. We compared brain activities measured while the subjects viewed achromatic grating stimuli before (PRE) and after the induction of the McCollough effect (POST) using functional magnetic resonance imaging (fMRI). There were two groups: one group was informed that they would perceive illusory color during the session (INFORMED group), whereas the other group was not informed (UNINFORMED group). The successful induction of the McCollough effect was confirmed in all subjects after the fMRI experiment; nevertheless, only approximately half of the UNINFORMED subjects had been aware of the color during the POST session, while the other half had not. The left anterior portion of the color-selective area in the ventral occipital cortex, presumably V4α, was significantly active in subjects who had consciously perceived the color during MR scan. This study demonstrates the activity in a subregion of the color-selective area in the ventral occipital cortex directly related to conscious color perception.
Year
DOI
Venue
2004
10.1016/j.neuroimage.2003.12.019
NeuroImage
Keywords
DocType
Volume
McCollough effect,Illusory aftereffect,Color perception,Awareness,V4 cortex,Functional MRI
Journal
21
Issue
ISSN
Citations 
4
1053-8119
1
PageRank 
References 
Authors
0.37
0
6
Name
Order
Citations
PageRank
Tomoyo Morita110.37
Takanori Kochiyama29814.14
T Okada310814.38
Yoshiharu Yonekura4233.47
Michikazu Matsumura510.37
Norihiro Sadato6558.22