Catastrophic interference

Catastrophic interference is when a computer learns something new that contradicts something it already knew. It happens when a computer is trying to learn many different tasks, but forgets how to do it the older tasks it previously knew how to do. It's like if you learned a lot of math and then had to learn a lot of Spanish. If you don't practice your math while you're trying to learn Spanish, then you might forget some of the things you knew about math.