What’s BMI and Why Should I Care?

BMI stands for Brain Machine Interface and will likely play a fundamental role in how we manage our biological and mental selves, and—in the long run—how we view ourselves as a species. I’m talking about controlling robots—and other machine parts outside and inside ourselves—with the mind.

Do you remember a few decades ago (the early 1980s) how Apostolos P. Georgopoulos of Johns Hopkins University recorded the electrical activity of single motor cortical neurons in macaque monkeys?
This was followed shortly after by some awesome experiments by Miguel Nicolelis and John Chapin at Hahnemann in the mid-1990s who taught rats in a cage to control a lever with their minds. Nicolelis and Chapin trained rats to press a lever with its forelimb to get water. They then fitted the rat’s head with a “brain-machine interface” (consisting of a little cap with connections wired to a computer). After getting used to pressing the bar for water, the experimenters disconnected the bar from the lever and the rats actually learned over time that they had to “think through” the motion of pressing a bar. Nicolelis and Chapin then applied a more sophisticated version of this experiment to monkeys in 2000, like Belle the tiny owl monkey, who learned to use her thoughts to direct the actions of a robot.

Now, here’s the cool part: Nicolelis and Chapin found that as the animal perfected its task, the properties of their neurons changed—over several days or even within a daily two-hour recording session. Gradual changes of neuronal electrical activity helps give the brain its plasticity, say Nicolelis and Chapin. “The number of action potentials a neuron generates before a given movement changes as the animal undergoes more experiences.” They, therefore, added a simple routine that let their model reassess the contribution of each neuron. Their BMIs can maintain viable recordings from hundreds to thousands of single neurons for months to years and utilize models that can learn, and therefore can handle evolving neurons, neuronal death and even degradation in electrode-recording capabilities. These researchers later discovered that the monkeys learned to use a BMI to control a robot arm without actually moving their own arms and, in fact, “incorporated the dynamic properties of the robot arm as if it were part of their own bodies.”

In 2004 Nicolelis and Chapin reported the first interaoperative demonstration of a BMI in human subjects.

What next?

Nicolelis and Chapin predict that BMIs might someday help patients suffering from seizures or a person whose limbs have been paralyzed by a spinal injury to move their “dead” limbs or other prosthetic with their minds, as if it was part of their biological system. For instance, the computer would convert the signals from a person’s mind through a neural chip in their brain into motor commands and dispatch them wirelessly to a different chip implanted in the person’s arm or prosthetic or wheelchair, etc.

Indeed, this technology promises to blur the biological from technological as our minds learn to interface both realms. Human and machine will indeed blur in the future. The future is here.

Nina Munteanu is an ecologist and internationally published author of novels, short stories and essays. She coaches writers and teaches writing at George Brown College and the University of Toronto. For more about Nina’s coaching & workshops visit www.ninamunteanu.me. Visit www.ninamunteanu.ca for more about her writing.