Conventional treatments with antidepressants can take a long time to work and ECT has numerous side effects.
Mayberg and her team have reported a 60 percent response rate among those who are out a minimum of one year. The first patients were operated on in Toronto in 2003.
"People aren't cured, but the continued stimulation seems to be safe and people are staying well," she said.
Earlier studies in sleep deprivation -- the quick fix of losing a night's sleep that soon disappears -- have informed this promising new research, according to Mayberg.
"That was the first clue as to how the switching mechanisms in the brain that hijack mood can be controlled," she said. "There may be a key to these switching mechanisms. Instead of taking a long time to work, we are working toward something that is faster acting."
But, she adds, "It's not a cure - there is a tendency to go back to an abnormal state and we don't understand why."
While research is still in its early phases, experts say a good night's sleep continues to be vital to health.
Sleep deprivation comes at a high cost, beyond basic exhaustion: reduced memory and impaired decision-making. It can even trigger a manic episode in people with bipolar disorder and cause epileptic seizures.
The psychological impact also takes a toll on physical health, according to Michele Okun, assistant professor of psychiatry and a research psychologist at the University of Pittsburgh's Sleep Institute.
She is studying how sleep impacts and increases the risk for pregnancy complications and perinatal depression. Research has shown a relationship between disturbed sleep and the inflammatory response associated with cardiovascular disease, diabetes and other metabolic disorders
"When you sleep, you have a reparation of a variety of systems," said Okun. "The immune system is revamped and restored. Growth hormones help repair body tissues."
Though there are many pieces to the sleep puzzle, scientists may one day find sleep-brain biomarkers that indicate who may be more vulnerable to depression and can curtail its onset by paying attention to their sleep habits.
"Feelings and emotions impact one's health through changes in the nervous and immune system just as positive emotions improve things," said Okun. "If you think about sleep, it's a behavior, like eating and drinking water and healthy behaviors like exercising and eating right. And it can be modified."