how to use handles key pressed to change 2 figures at once?

Hello all. I have folder path1 which contains 10 images. and folder path2 which contains 10 images. I have a costume matlab function that plots a image#1 from a certain path. when pressing on a keyboard key, the image changed to image#2 and so on. I want call the same function again, only on different path, so each time I press on the keyboard, both of the figures will changes. meaning- no matter which figure was "on" when I pressed the key, both figures will now show image#i.

Can anyone help me with a simple template for this matter? I don't know how to work with handles very well. nor do I found a good guide. thanks,