Guest Column | July 16, 2013

Memory Chips, or Prosthetic Devices for the Brain

Have you ever had a moment where you couldn't remember the name of someone you knew? Felt that the name was right there, knocking at the front door of your brain, but you couldn't figure out a way to let it in? Or a conversation when the word you wanted to use just fluttered away, and no matter how hard you tried to grab it, it refused to be caught?

Moments like these affect many people on a daily basis. Often it is a fleeting moment of confusion, of forgetfulness. It isn't a harbinger of anything wrong, just a momentary lapse in an otherwise efficient brain. Sometimes, however, it could be related to a form of dementia, such as Alzheimer's disease. The National Institute on Aging (NIA) describes how persons with Alzheimer's disease may have plaques and tangles in the brain as well as degeneration of neural pathways, which can lead to memory loss and decreasing mental functionality.

Who does Alzheimer's disease impact?
According to the NIA, this disease may affect as many as 5.1 million Americans, especially those over the age of 60. The aging of a large segment of the U.S. population, the baby boomers, may bring more attention to concerns such as dementia for tomorrow's health care providers. Diverse professionals including medical researchers, nurses and psychiatric technicians may all be involved in treating those with Alzheimer's. The Bureau of Labor Statistics notes that registered nurses can play an important role in facilities that care for individuals with the disease. RNs may focus on different health conditions or groups of people, for example, a geriatric nurse works with the elderly, who are at risk for dementia. Occupational therapy can also be a key part of treatment for patients with conditions such as Alzheimer's, the BLS reports.

Currently there is no cure for Alzheimer's, but the NIA describes research efforts to slow or delay its effects. What if we could help individuals with this disease remember a little bit more? What if there was a way to help repair their faulty recall, so that they could retrieve more of their memories? Luckily someone has been working for over 35 years in order to do just that -- Theodore Berger.

The quest for memory implants
A University of Southern California biomedical engineer and neuroscientist, Theodore Berger has spent the better part of his career trying to develop a way to duplicate the electronic signals that the brain uses to communicate. His research includes the creation of a silicon implant functioning to replace damaged parts of the brain that help turn short-term memories into long-term ones. These areas of the brain are among those affected in Alzheimer's patients and individuals with massive brain trauma.

Berger started his trek in the 1970s as a graduate student at Harvard, under the tutelage of Richard Thompson. Thompson was studying changes in the brain that impacted the ability to learn. He experimented on rabbits, teaching them to blink by using a tone and a light gust of air on the eyes. Using electrodes to track the impulses fired by the brain during this process, Berger and Thompson were able to monitor spikes in hippocampus activity that lead them to believe that this was the center of learning.

Berger built on these experiments and studied the hippocampus further while at the University of Pittsburgh in the 1980s. In partnership with Robert Sclabassi, Berger observed rabbits, using electrical impulses to stimulate the hippocampus in order to understand the neuronal network in that region of the brain. Berger told the MIT Technology Review that their research showed signals overlapping in the brain, without "linear activity."

Exploring the brain
In the 1990s, Berger moved his work to USC and teamed up with biomedical engineer Vasilis Marmarelis. Berger told MIT Technology Review: "It became obvious that if I could get this stuff to work in large numbers in hardware, you've got part of the brain. Why not hook up to what's existing in the brain?" Berger and Marmarelis began using slices of the hippocampus region of rats. Knowing that electrical impulses were transmitted through the hippocampus, they induced random impulses and recorded how these signals were transformed in the region. They then converted these signals into mathematical equations, and put those equations onto computer chips.

After testing the chips on the hippocampus slices, Berger and Marmarelis began testing with live rats. They started by training the rats to press one of two different levers in order to earn a treat. While the rats were doing this, Berger and Marmarelis recorded the signals in the hippocampus, hoping to capture the code as it was being transferred from short-term to long-term memory. After doing this for a time, and believing that they had successfully recorded and could replicate the coded signal, the researchers then administered a drug to the rats that inhibited their ability to create long-term memories, which would keep them from remembering the specific lever that allowed them to earn the treat. Using the computer chips to simulate the signals sent by the hippocampus, Berger and Marmarelis found that the rats were able to remember which lever produced the treats.

What happens now?
After testing implanted electrodes on primates last year, Berger hopes that he and others at USC can start trialing internal implants. Berger admits some uncertainties -- perhaps the equations that he has come up with are just for the specific tasks he has trialed them for.

Human tests may also be on the horizon. Researchers at USC are testing the use of electrodes in people with epilepsy, and Berger hopes to study what they do to improve upon his techniques, and also mine memory codes from them.

Berger expressed optimism about his research in the MIT Technology Review: "I do think we're going to find a model that's pretty good for a lot of [neurological] conditions and maybe most conditions."

High-tech innovations in the field of prosthetics are exploring the possibility of artificial limbs connected to the nervous system, and Berger's research introduces the idea of prosthetic devices for the brain. Someday, individuals with severe brain trauma, Alzheimer's or other debilitating diseases that impact the mind could potentially use an implant to help them retrieve more of their memories. "If I can give them the ability to form new long-term memories for half the conditions that most people live in," Berger says, "I'll be happy as hell, and so will [be] most patients."

About the Author
Jamar Ramos has been writing poetry and fiction for many years, and earned his bachelor’s degree in Creative Writing from San Francisco State University. For the last three years, Mr. Ramos switched to producing blog posts for CBSSports.com and writing professionally as an independent contributor for a number of Internet sites. His creative works have been featured in The Bohemian and The San Matean. He now contributes articles for OnlineDegrees.com, OnlineColleges.com, and AlliedHealthWorld.com.

This article is originally published on AlliedHealthWorld.com