Now We Can Control Rat Brains
I’ve never been hypnotized before. But I’ve tried! When I was a kid, we once had a hypnotist come to an assembly in my school. He asked for volunteers to queue up at the front of the gymnasium, so I hopped in line with a few of my friends. Pretty soon, my friends were barking like dogs and squawking like birds!
But for some reason, the hypnosis just didn’t work for me, or for a few of the other students. The hypnotist said that some people just don’t seem to be as susceptible to hypnosis as other people, for all sorts of reasons. I was a little bit bummed because it looked like all my hypnotized friends were having a great time acting like animals, but I was a little bit proud of myself at the same time for being impervious to the mind control attempts of the hypnotist.
A new study in the journal PLOS One just showed off a new kind of mind control that could be a lot more effective than hypnosis, however. A team of researchers from Harvard, Boston University, and Korea University in Seoul successfully created a brain-to-brain interface (BBI) between a human and a rat, essentially allowing a person to control a rat using nothing more than thoughts. Here’s how it works:
First, a person is seated in front of a computer screen, on which a strobe light occasionally flickers. Electrodes are attached to the person’s head, so that a computer can record the electrical activity going on in their brain.
The electrical signals from the person’s brain are fed into another computer attached to a focused ultrasound (FUS) machine, which uses sound waves to modify how brain cells behave (see my article for an overview of other ways to stimulate the brain). The computer is programmed so that when the person’s brain waves act a specific way, the FUS machine turns on and delivers a burst of stimulation.
Finally, a rat is positioned under the FUS machine, so that the FUS stimulation will zap the part of its brain responsible for tail movements. So in a nutshell, if the person in the BBI thinks a specific thought, it will cause the rat’s tail to move, whether the rat likes it or not. You can see a video of the whole process here.
Reasonable people can have a lot of different reactions to a study like this. Some people might think, “They made a rat’s tail move – who cares?” Others (myself included) will view this as a groundbreaking demonstration of a new way to understand how our brains work. Still others may think this is a terrifying new way for people in power to control those that are beneath them.
Whatever your feelings about this study, I think it’s safe to say that we’re a long way from actually using a BBI to control another person with our thoughts. But it’s also clear that we’ve found a much more direct means to control brain patterns than hypnosis! I won’t be surprised at all if, in the next 20 years, neuroscientists replace hypnotists at school assemblies. I’ll be at the front of the line to try it out.