Difference between seeing a random color dot picture and reading shapes from the same color dot picture in the Ishihara pseudoisochromatic plates

When we are viewing colored picture, what is the difference in our brain between a random Color dot picture and a digit figure pattern picture seen through its colored dots? We created 3 patterns that are a functional magnetic resonance imaging version of the Ishihara plate patterns to test multiple color-sensitive areas in human ventral occipitotemporal cortex. The results showed that area V4 is activated by the stimulus of reading shapes from its color dots in the Ishihara pseudoisochromatic plates but not by the stimulus of seeing a random color dot picture. We suggest that area V4 is activated not by color processing but by segregation.