How Areas of Ventral Visual Stream Interact When We Memorize Color and Shape Information

We studied the role of ventral visual cortex areas in processing color and shape information during memorizing these characteristics. The participants (22 people) were presented with blots of different colors and shapes (9 shapes, 8 colors). There were 3 experimental series in which participants had to memorize shape, color, or both characteristics at once. A control block was also conducted, in which the task was to count the number of the same color images. EEG was recorded, then the brain activity sources were localized. Also, we calculated the connectivity parameters (via Granger causality method). During memorizing colors, we found strong connections between the V3v and hV4 areas. During memorizing the shape, connection between the VO1 areas in both hemispheres was found. When both characteristics were memorized, we found connections between the V3v, hV4, and VO1 areas. In addition, connections were observed between the VO1 and VO2 areas of both hemispheres. We suggested that hV4 and VO1 areas are related to color and shape processing, respectively. In VO2 area all characteristics are integrated into a holistic image of perception.