Scientists catch cells in the act of remembering

Scientists have for the first time recorded individual brain cells in the act of summoning a spontaneous memory, revealing not only where a remembered experience is registered but how the brain is able to re-create it. The recordings, taken from the brains of epilepsy patients being prepared for surgery, demonstrate that these spontaneous memories reside in some of the very same neurons that fired most furiously when the recalled event was first experienced. Researchers had long theorized that this was the case but until now had only indirect evidence. The new study, experts said, has all but closed the case: Remembering, for the brain, is a lot like doing. The experiment, being reported Friday in the journal Science, moved beyond most earlier memory research in that it focused not on recognition of objects or recall of specific words or symbols but on free recall - whatever popped into people's heads when, in this case, they were asked to recall a series of short film clips they had just seen. Such memory often deteriorates quickly in people with Alzheimer's disease and other forms of dementia, and it is critical to so-called episodic memory: the rich catalog of vignettes that together form our remembered past. "This is what I would call a foundational finding," said Michael Kahana, a professor of psychology at the University of Pennsylvania. "I cannot think of any recent study that's comparable. It's an important step in helping us fill in the detail of what exactly is happening when the brain performs this mental time travel" when summoning past experiences.

In the study, a team of American and Israeli researchers threaded tiny electrodes into the brains of 13 people with severe epilepsy. The electrodes allow the doctors to pinpoint the location of the mini-storms of brain activity that cause epileptic seizures.

The patients watches a series 5- to 10-second film clips, some from popular TV shows like "Seinfeld," others depicting animals or landmarks, like the Eiffel Tower. The researchers recorded the firing activity of about 100 neurons during the viewing of repeated series of videos; the cells were concentrated in and around the hippocampus, a sliver of tissue deep in the brain that is known to be critical to forming new memories.

In each individual, the researchers identified single cells that became highly active during some videos and quiet during others. About half the recorded cells hummed with activity in response to at least one film clip, and responded weakly to another.

After distracting the patients for a few minutes, the researchers then asked the subjects to think about the clips for a minute and report "what comes to mind." The patients remembered almost all of the clips. And, sure enough, when they recalled a specific one - say, a clip of Homer Simpson - the same cells that had been active during the Homer clip reignited. In fact, the cells became active a second or two before people were conscious of the memory.

In effect, the scientists could identify the specific memory before the patients could.

"There were all these distractions, these people were on a noisy ward, there's a whole lot happening all around them, but still you see this absolutely robust response in the individual neurons," said the senior author, Dr. Itzhak Fried, a professor of neurosurgery at the University of California, Los Angeles, and the University of Tel Aviv. His co-authors were Hagar Gelbard-Sagiv, Michal Harel and Rafael Malach of the Weizmann Institute of Science in Israel; and Roy Mukamel, of UCLA.

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Is this a step backwards or forward for our brain? Yes it is cool that they can now relatively pinpoint neurons responsible for remembering BUT, instead of forcing our brains to remember certain events, would there be a "Pill" that will enable us to do so?

If so, wouldn't that be an act of involuntary action? I mean, you will be taking pills to remember, so what happens when you forget to do so? Why can't they just come up with something really useful to help our brain grow instead of shrinking it by substance?

I know they are not even close to creating such pill but I am just looking ahead for what may be coming.

They've been looking into this for a while.
In order to make some pill or treatment for trauma.
If they could give the person a pill or injection or something to forget most of an incident right as it happened they say it would aid in the persons recovery.
I guess now they have actually pinpointed the process.
So im sure we aren't that far away from making a forget about a painful experience pill.
But of course they will mess all that up and it will have some serious side effects that turn you into a psychotic killer or makes your liver explode or something.

First of all, it is a really serious step to further understanding the brain. So - deep respect to guys who did it.
As for pill- i do not think that there ever will be a pill. However brain implants or even external device (probably by magnetic field) that can create/store memories or even give "experience" - will be available for sure. This century. Homo Sapience ----> Homo Cybergus.

Hi I'm a third year pharmaceutical chemistry student and while I am no expert I dont think that you could design a pill to stimulate specific memory cells to trigger the perception of a memory. I think they could perhaps make a memory pill so that all memories are stimulated. That would be quite cool actually.... might be a bit scary.... But I think if they wanted to provoke specific memories to surface they are more likely to use direct electrical stimulation using electrodes or something like that.