When you're hungry, it can be hard to think of anything other than food. When you're desperately poor, you may constantly worry about making ends meet. When you're lonely, you might obsess about making friends. This week, as part of our You 2.0 series, we bring you a favorite 2017 episode about the psychological phenomenon of scarcity. Researchers say this form of tunnel vision can affect our ability to see the big picture and cope with problems in our lives.