The researchers thought that if they could stimulate the brains of obese patients, maybe they would be able to lose weight. The researchers chose nine obese patients who were each staying at the facility for two eight-day stints. On the first visit, patients were all given sham transcranial direct current stimulation (tDCS), a method in which low-amplitude current is sent to the brain through electrodes stuck to the scalp—in the sham version, patients are hooked up to the machine but no electricity comes out. But during the last three days of the second visit, five patients were given active tDCS, and the other four were again given sham tDCS. Then, all patients were allowed to go to the vending machine and pick whatever food or drink they wanted. The researchers found that the patients who received active tDCS consumed an average of 700 fewer calories than they had during their first hospital stay, and lost an average of 0.8 pounds.