Think about an implantable device on your head that helps you better recall everything. Well, that sounds a lot like a device showed in an episode of Black Mirror, but in reality, someone is actually working on a not that perfect but similar device. Theodore Berger, a biomedical engineer at the University of Southern California is working on memory enhancement in a form of prosthesis, surgically implanted directly into the brain.
The prosthesis can act like an artificial hippocampus by electrically simulating the brain in a specific way to build memories. Its aim is to convert short-term memory into long-term memory and just like the hippocampus, to store it.
Berger’s experiment started by teaching a rabbit to engage an audio tone with air puffed into the rabbit’s face, making it blink. Berger could observe patterns of activity firing off in the rabbit’s hippocampus with the help of electrodes attached to it. He refers this firing pattern as a space-time code, describing where the neurons are in the brain and when they fire.
“As the space-time code propagates into the different layers of the hippocampus, it’s gradually changed into a different space-time code,” Berger says. “And we don’t understand why, but when it comes out, that space-time code is what the rest of the brain can recognize and use as a long-term memory.”
The memory, which the rest of the brain uses as a signal to make the rabbit blink, is represented by the outgoing code. Berger claims he could mathematically model the general rule, which the hippocampus uses to transform short-term memories into long-term memories.
He then built an artificial rat hippocampus, an experimental prosthesis, with the general rule in hand. He taught the rats with electrodes monitoring their hippocampus to press a lever and was able to obtain the corresponding space-time codes. He then ran the code through his mathematical model and sent it back to the rats’ brain. And, you know what? The rats successfully pressed their levers, validating Berger’s system.
“They recall the correct code as if they’ve created it themselves,” Berger says. “Now we’re putting the memory back into the brain.” He also tried out the prosthesis in rhesus monkeys, which successfully improved its memory.
And, now, it’s time to implant it on a human. But, could this similar implant really work on the human brain? “All of these prosthetics interfacing with the brain have one fundamental challenge,” Dustin Tyler, a professor of engineering at Case Western Reserve University cautioned Wired. “There are billions of neurons in the brain and trillions of connections between them that make them all work together. Trying to find technology that will go into that mass of neurons and be able to connect with them on a reasonably high-resolution level is tricky.”
However, being optimistic, Berger told IEEE Spectrum “We’re testing it in humans now, and getting good initial results. We’re going to go forward with the goal of commercializing this prosthesis.”
Syncing up with Kernel, Berger is planning to market the implant as a medical device, which can be helpful to the memory impaired. With a version of this implant, he is currently conducting a human trial, and so far his patients are responding well to the memory test. This could be a revolutionary device to help people suffering from Alzheimer, as well as to enhance human intelligence in areas such as creativity, attention, and focus.