how to apply contrast to different image?

I have a grayscale image that I open in a figure with the contrast tool opened with "imcontrast". I also have GUI, and in that gui the same image is opened. what I would like to do is whenever I adjust the contrast on the 1st image, the contrast of the second image will be changed as well. in other words, I want to change the contrast of two images (which are the same image) with only 1 imcontrast tool