Scientists Find That Memories Can Be Saved With Pulses Of Electricity : Shots - Health News Technology that uses electrical stimulation to tweak the brain may eventually help people with memory problems caused by a brain injury or Alzheimer's disease.

A Tiny Pulse Of Electricity Can Help The Brain Form Lasting Memories

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Scientists have shown that a tiny pulse of electricity delivered to just the right place in the brain can improve a person's memory. This technology could one day help people whose memories have been impaired by a brain injury or by Alzheimer's disease. Here's NPR's Jon Hamilton.

JON HAMILTON, BYLINE: Forming memories is never a sure thing. Michael Kahana of the University of Pennsylvania says the brain often fails to store information we want it to keep.

MICHAEL KAHANA: When we're trying to study a list of items - for example, for a test - sometimes the items stick, and sometimes we have momentary lapses where it seems like the items are going by and we don't seem to remember anything.

HAMILTON: Kahana is part of a team that thought they might be able to help the brain do better. So they had a computer learn to recognize signals indicating that the brain was about to have a memory lapse. Kahana says then they had the computer intervene by delivering a pulse of electricity.

KAHANA: When we stimulated the left temporal cortex, we found that memory was improved significantly. And when we simulated other parts of the brain, memory was by and large impaired.

HAMILTON: Kahana says when a pulse reached the left temporal cortex at just the right time, people remembered about 15 percent more words from a list they'd studied. The experiment was done in 25 patients with epilepsy who were waiting to get surgery for their seizures. Dr. Michael Sperling of Thomas Jefferson University in Philadelphia says that allowed direct access to their brains.

MICHAEL SPERLING: Patients are in a hospital bed, typically, or in a chair in their room with electrodes in their brain, wire then coming out, linked to a system.

HAMILTON: But there could be a problem with that. Sperling says epilepsy patients tend to have memory problems and brains that aren't typical. He says that makes it tricky to evaluate the new treatment.

SPERLING: We know that it has some benefit in people with epilepsy. We still really lack any experiments in people with other conditions to know for certain whether it would prove effective or not.

HAMILTON: Even so, Sperling is optimistic that the research will lead to an implantable device that can improve memory.

SPERLING: There's a good chance that something like this will come available. I'm not exactly sure when. I would hope within the course of the next half dozen years or so.

HAMILTON: The research is funded by the military's Defense Advanced Research Projects Agency. Dr. Justin Sanchez directs the Biological Technologies Office at DARPA. He says the initial goal was to help military personnel and veterans with memory problems caused by brain injuries.

JUSTIN SANCHEZ: We didn't just do this for the sake of science. We wanted a real technology that could ultimately make its way out into the world after the DARPA investment is done.

HAMILTON: Sanchez says an implanted device that improves memory could also make a difference to people with Alzheimer's. And he said the technology might eventually help anyone who just wants to remember things better.

SANCHEZ: If any of us could get a 15 percent boost in our memory in our everyday lives, that would be transformative. Just think if you're trying to recall a phone number, if you're trying to recall a friend's name.

HAMILTON: The research appears in the journal Nature Communications. Sanchez says scientists are already working on ways to miniaturize the technology. Jon Hamilton, NPR News.


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