I can't get my Canon Camera to show up on my Macbook Pro?

I have a mid 2012 Macbook Pro (no retina), and I just recently upgraded to a new camera, the Canon Rebel t4i, which I used once with my laptop for remote shooting. Obviously, that time my camera was hooked up to my laptop and everything worked fine. Today however, I tried hooking it up and my mac wouldn't even recognize it's existence. Image capture would also come up with nothing. I have two Canon camera cord so I tried both, but neither is working properly with the computer, and even my old camera, the Canon Rebel xsi, is not showing up. I'm really confused since the usbs work properly for everything else, and both of the cords worked just a couple of weeks ago. I also updated everything. Help?