Most patients with severe depression who tried vagus nerve stimulation in a big US trial saw benefits. About 70% saw positive changes. These patients did not respond with drugs or therapy at all. The device sends small electric signals to a nerve connecting the brain to the gut. It did not cure depression but gave relief that grew stronger over time.
A limited group of patients in Australia tested a similar implant. Their mood improved and held for a long period. Tests with creatine also suggest it might help mood, but scientists say more work is needed before drawing conclusions.