What is the best alternative to plotting a figure with colors in an article? I would like to add this plot to my article but it has lots of colors which I'm not in favor of. This figure represents a continuous value as a function of the number of sources that has been calculated for two different categorical parameters (prior knowledge and number of voxels). I appreciate your ideas on how to modify and enhance this figure.
If you don't want to use colors, you could use patterns instead. Here is an example:

Image Source