The mortgage REIT sector has taken a beating this summer. Changes in interest rates, driven by talk from the Federal Reserve, has sent stock prices plummeting for the big names like American Capital Agency (AGNC 0.97%) and CYS Investments (NYSE: CYS), as well as for smaller players like Invesco Mortgage Capital (IVR 1.54%).

In the video below, Motley Fool contributor Jay Jenkins takes a step back to better understand what's happening in this sector, and specifically, how a company like Invesco Mortgage makes money.