Machines with brains seem all the rage right now. But the risk is great, because those brains could become better than ours. The greater challenge, then, is to build an interface that allows our own brains to control powerful machines. Taking a step in that direction, researchers from Duke University have built a system that lets monkeys control wheelchairs with their thoughts alone. To achieve this feat, they first implanted hundreds of tiny wires in two parts of the brain: the pre-motor (which helps plan movement) and the somatosensory cortex (which understands the sensation of touch). Then they drove monkeys in wheelchairs and monitored how some 300 neurons in those regions responded. With that data, they built a computer program for a wheelchair that took commands directly from monkeys’ brains. The researchers write in Scientific Reports that, as the primates waddled around, they learned to control the brain-machine interface better and reached the target bowl of grapes faster. At the same time, the researchers improved their algorithm to better understand the monkeys’ thoughts. The technology seems promising, but it will have to overcome two barriers to become useful to humans. First, the researchers will have to improve the device to work in the real world with far more obstacles and then translate it to a human brain. This they hope they can do by monitoring more neurons and increasing the fidelity of the signal. Second, even though they rejected using non-invasive technology such as EEG to measure neuronal activity for these experiments, they may have to consider that option if their wheelchairs are to become widely used. Not many people will be interested in having wires implanted in their brains, but we can assume they would be more comfortable wearing a helmet that reads the electrical signals that neurons produce. The optimistic upshot of their work is that, if primate brains can adapt to using machines, then human brains most likely would do so too. And that is a powerful thought.