If you've ever been unemployed or been laid out with an injury or voted for the losing candidate, you know how hopeless things can seem in a bad situation. The psychological phenomenon of learned helplessness is that, magnified: it's the tendency for you to stop looking for work after a handful of failed interviews, the way you might give up on starting an exercise routine because you've hurt your back one time too many, or the desire to stay in on voting day because past elections have taught you your vote doesn't matter. In the extreme, it's why people don't leave their abusers and why prisoners don't try to escape.

As a young graduate student, Martin Seligman assisted in a study on the Pavlovian response in dogs—that is, the way that you can teach dogs to associate a bell with food so that they start to drool just at the sound of that bell. Except in this case, the study focused on the opposite: when dogs learned to associate a tone with an electric shock, would they jump out of the way just at the sound of the tone? It turns out that yes, they would—most of them. But Seligman noticed something strange. When some dogs got a new electric shock, they just stood there. They didn't try to avoid it. Their inability to prevent the shock early on in the experiment had taught them there was no point in even trying.

Seligman called this tendency learned helplessness, and it was at the center of many research projects to follow. He found that the phenomenon applied in many different situations and subjects, and once it set in, it was difficult to reverse—one study found that dogs still made no move to avoid an electric shock even a week later.

Before you write off Seligman as a mad scientist who enjoys electrocuting animals, you should hear what he did next. He set out to determine how, if at all, subjects could learn to reverse this tendency. He found that a small tweak could drastically change how subjects respond to a bad situation: in the aforementioned study, if dogs had their first shocks in a situation where they could get away, even if they were trapped for subsequent shocks, they made a significantly greater effort to avoid all future shocks. Seligman theorized that those first experiences taught them that not all shocks were equal—that is, some situations are less hopeless than others. He also found that this applies to people: the way we interpret bad situations has a big impact on our depression risk. If you think that bad things will keep happening and you're always to blame, you're more prone to depression; if you think your bad situation will go away soon and that it wasn't your fault, you tend to have a better outlook on life overall.

Here's the good news: if you're in the former camp, there are ways to put a stop to that negative thinking. In a 1995 study of elementary-school children with depression, Seligman and his team found that the kids who were taught to reframe their thoughts to be less pessimistic and self-blaming experienced much less depression. He calls this idea "learned optimism," and therapists trained in cognitive behavioral therapy help their clients do just that. Learn more about how your outlook shapes your experience in the videos below.