Smallwood’s experiment led Perkins to hypothesize that the brains of neurotic people are storm-cloud factories.

“It seems like these people have spontaneous brain activity that’s firing off, there’s a trickle-down effect, and it feeds into their more basic threat-processing systems,” he said. “They’ll be sitting in an armchair and their heart rate is 200 and they’re panicking and sweating.”

These negative self-generated thoughts aren’t completely unrealistic, Perkins notes. Neurotic people don’t fear the earth will be invaded by aliens tomorrow. They think their wife will cheat on them on a business trip, even if she’s the most loyal and loving woman in the world.

Strangely, these melancholy thoughts also have an upside: They help in planning, delaying gratification, and, some studies show, with creativity. The more you keep your life’s big problems “constantly before you,” as Newton did, the likelier it is you’ll resolve them.

If these melancholy thoughts have upside is it better to have them or not?

As tortured as a neurotic's life must be, it's their normal.  

The article suggests the genius in all of us is borne from compensating for some pain or uncomfortable feelings.  We're continually solving ourselves. 

Yes, I've heard that referred to as Kaizen. 

And I'm glad some good can come from melancholy thoughts.