The Naval Special Warfare Development Group, also known as Seal Team Six, is just one of the United States Navy teams testing out technology that would zap soldiers' brains with electricity to boost their cognitive skills.

Not only has the Navy been using neuro-stimulation to try and enhance the mental and physical performance of its service members — they've also asked industry contractors to develop more cognitive-enhancement technologies, according to a report from the news site Military.com.

Former Defense Secretary Ash Carter said last July that the Department of Defense planned to test headsets made by tech company Halo Neuroscience, which he believed could enhance the combat skills of special operators. Halo Neuroscience also offers a civilian product, Halo Sport. The company claims their headsets pulse energy into the motor cortex, the area of the brain in charge of movement, thereby boosting focus, coordination, endurance, and strength. However, some research has shown this technique — transcranial direct-current stimulation (tDCS) — has no effect that is better than a placebo.

But that hasn't discouraged the Pentagon from pushing forward with tDCS research and testing. "We plan on using that in mission enhancement," Rear Adm. Tim Szymanski, commander of Naval Special Warfare Command, said at a military conference in February, in which he encouraged developers to dream up more brain-boosting tech. "The performance piece is really critical to the life of our operators."

Syzmanski later told Military.com why he believed that tDCS could help create super soldiers. "In experiments, people who were watching these screens … their ability to concentrate would fall off in about 20 minutes," Szymanski said. "But they did studies whereby a little bit of electrical stimulation was applied, and they were able to maintain the same peak performance for 20 hours."

Since Carter's announcement last summer, SEAL teams have been testing the technology. Capt. Jason Salata, a spokesman for Naval Special Warfare Command confirmed that volunteer groups were participating in a specific neuro-stimulation cognitive enhancement project, but would not say how many service members are involved. He also would not comment on specifics, but said, "early results show promising signs."

According to Halo Neuroscience chief technology officer Brett Wingeier, their devices are being used at five military bases. Szymanski suggested the Navy is also interested in performance enhancing pharmaceutical supplements like blood testosterone.

This article originally appeared at Vocativ.com: U.S. Navy is zapping SEALs brains to make them super soldiers.