It’s been 30 years since the first message was sent over initial nodes of the Arpanet, the Pentagon-sponsored precursor to the internet. But this month, researchers announced something that could be equally historic: the passing of messages between two rat brains, the first step toward what they call the “brain net”.

Connecting the brains of two rats through implanted electrodes, scientists at Duke University demonstrated that in response to a visual cue, the trained response of one rat, called an encoder, could be mimicked without a visual cue in a second rat, called the decoder. In other words, the brain of one rat had communicated to the other.

"These experiments demonstrated the ability to establish a sophisticated, direct communication linkage between rat brains, and that the decoder brain is working as a pattern-recognition device,” said Miguel Nicolelis, a professor at Duke University School of Medicine. “So basically, we are creating an organic computer that solves a puzzle."

Whether or not the Duke University experiments turn out to be historic (some skepticism has already been raised), the work reflects a growing Pentagon interest in neuroscience for applications that range from such far-off ideas as teleoperation of military devices (think mind-controlled drones), to more near-term and less controversial technology, like prosthetics controlled by the human brain. In fact, like the Arpanet, the experiment on the rat “brain net” was sponsored by the Defense Advanced Research Projects Agency (Darpa).

The Pentagon’s expanding work in neuroscience in recent years has focused heavily on medical applications, like research to understand traumatic brain injury, but a good portion of the past decade’s work has also been on concepts that are intended to help the military fight wars more effectively, such as studying ways to keep soldiers’ brains alert even after days without sleep. Under the rubric of “Augmented Cognition,” Darpa has also pursued a number of military technologies, like goggles that would monitor a soldier’s brain signals to pick up potential threats before the conscious mind is aware of them.

Now, such work may get an even bigger boost: President Barack Obama is set to announce an initiative that could funnel billions of dollars to the field of neuroscience. That could mean more money for the Pentagon’s forays into brain science.

While some of the applications might be a generation away, or may never arrive, like mind-controlled drones, others, like the brain-monitoring goggles, are already in testing (though probably not ready for use in the field). That’s raising questions from ethicists, who are pushing for the government to begin now to think about “neuro ethics.”

In a 2012 article published last year in the journal Plos Biology, Jonathan Moreno, a professor of medical ethics, and Michael Tennison, a professor of neurology, argued that many neuroscientists don’t think about the contribution of their work to warfare, or consider the ethical implication of such work.

The question they raise is what choice future soldiers might have in such cognitively enhanced warfare. “If a warfighter is allowed no autonomous freedom to accept or decline an enhancement intervention, and the intervention in question is as invasive as remote brain control,” they write, “then the ethical implications are immense.”

Whether this era will come to pass, remains to be seen. But, for now, expect many more advances in the world of neuroscience to come from the Pentagon.

Visitors to the SXSW Festival in Austin, Texas, can hear Sharon talk in more detail about the Pentagon’s growing interest in neuroscience in her talk A Manhattan Project of the Mind on 12 March.

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