Machines That Translate Wants into Actions

Neuroscientists have labored for decades to find ways to connect human brain impulses to physical actions, with limited success.

Most people walk or grasp a cup without thinking about it, but those with brain or nerve impairments struggle with such simple tasks. New brain-machine interface (BMI) technology holds out the promise that their brains can move physical objects and limbs, using conscious thoughts.

Some current devices use “write-in” BMIs to transmit electrical impulses to neural tissues. One example is cochlear implants, which enable deaf people to hear by stimulating the auditory nerve. Retinal stimulators are being tested on blind patients. Parkinson’s disease can be somewhat mitigated by stimulating parts of the brain that control motor activity.

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