In-brain monitoring shows memory network

This shows Dr. Nitin Tandon, University of Texas Health Science Center, operating to place electrodes on the brain of a patient. The electrodes record electrical activity in the brain and can be used both to monitor seizures and for research into memory by Arne Ekstrom at the UC Davis Center for Neuroscience. Credit: Nitin Tandon, University of Texas Health Science Center, Houston

Working with patients with electrodes implanted in their brains, researchers at the University of California, Davis, and The University of Texas Health Science Center at Houston (UTHealth) have shown for the first time that areas of the brain work together at the same time to recall memories. The unique approach promises new insights into how we remember details of time and place.

"Previous work has focused on one region of the brain at a time," said Arne Ekstrom, assistant professor at the UC Davis Center for Neuroscience. "Our results show that involves simultaneous activity across ." Ekstrom is senior author of a paper describing the work published Jan. 27 in the journal .

Ekstrom and UC Davis graduate student Andrew Watrous worked with patients being treated for a severe seizure condition by neurosurgeon Dr. Nitin Tandon and his UTHealth colleagues.

To pinpoint the origin of the seizures in these patients, Tandon and his team place electrodes on the patient's brain inside the skull. The electrodes remain in place for one to two weeks for monitoring.

Six such patients volunteered for Ekstrom and Watrous' study while the electrodes were in place. Using a laptop computer, the patients learned to navigate a route through a virtual streetscape, picking up passengers and taking them to specific places. Later, they were asked to recall the routes from memory.

This is a diagram of locations in the brain monitored by electrodes in some of Dr. Nitin Tandon's patients (UTHealth), also being used for research into memory by Arne Ekstrom at the UC Davis Center for Neuroscience. Credit: Nitin Tandon, University of Texas Health Science Center, Houston

Correct memory recall was associated with increased activity across multiple connected brain regions at the same time, Ekstrom said, rather than activity in one region followed by another.

However, the analysis did show that the medial temporal lobe is an important hub of the memory network, confirming earlier studies, he said.

Intriguingly, memories of time and of place were associated with different frequencies of across the network. For example, recalling, "What shop is next to the donut shop?" set off a different frequency of activity from recalling "Where was I at 11 a.m.?"

Using different frequencies could explain how the brain codes and recalls elements of past events such as time and location at the same time, Ekstrom said.

"Just as cell phones and wireless devices work at different radio frequencies for different information, the brain resonates at different frequencies for spatial and temporal information," he said.

The researchers hope to explore further how the brain codes information in future work.

The neuroscientists analyzed their results with , a new technique that is being used for studying networks, ranging from social media connections to airline schedules.

"Previously, we didn't have enough data from different regions to use graph theory. This combination of multiple readings during memory retrieval and graph theory is unique," Ekstrom said.

Placing electrodes inside the skull provides clearer resolution of electrical signals than external electrodes, making the data invaluable for the study of cognitive functions, Tandon said. "This work has yielded important insights into the normal mechanisms underpinning recall, and provides us with a framework for the study of memory dysfunction in the future."

More information: Human Spatial Cognition Lab: www.humanspatialcognitionlab.org/

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TheGhostofOtto1923
1.4 / 5 (9) Jan 29, 2013
The beginnings of direct memory outsourcing and augmentation? Not soon enough-
TheGhostofOtto1923
1 / 5 (7) Jan 30, 2013
Just think - in a decade or 2 most of the sort of work bring done by the guys in the picture above, will be done by robots. Safer, much cheaper. Obamacare will allow this to happen.

What will doctors do then? Robot repair won't pay nearly as much-
Fabio P_
5 / 5 (1) Feb 04, 2013
@Otto: I'm not sure what that has to do with the article, but nevertheless, I'm afraid you're being overly optimistic. Brain surgery - or any surgery, for that matter - is an activity that require complex on-line thinking and great flexibility. Since that makes it impossible for surgery to be a priori automatised, what you're saying is that within a decade or two we will have created a true artificial intelligence. While that would be awesome, I have my doubts that will actually be the case.
TheGhostofOtto1923
1 / 5 (5) Feb 04, 2013
@Otto: I'm not sure what that has to do with the article, but nevertheless, I'm afraid you're being overly optimistic. Brain surgery - or any surgery, for that matter - is an activity that require complex on-line thinking and great flexibility.
This is what they were saying about self-driving vehicles only a few years ago. Robots have unwavering concentration and instant access to unlimited info, including human consultants.

Their senses and motor skills are far superior to those of any human, and they are not susceptible to fatigue, illness, aging, emotion, or greed.

Brain surgery may be more an art for humans because of their inherent limitations. Machines will be able work much faster in much more detail. They will respond to multiple sensory input instantly, unlike humans who are limited to one point of view. Robots cannot help but replace us.
TheGhostofOtto1923
1 / 5 (5) Feb 04, 2013
Since that makes it impossible for surgery to be a priori automatized
What you are saying is that ad libbing and winging it cant be automated. Machines wont need to do these things. The human body is a machine and it can be repaired as such.
what you're saying is that within a decade or two we will have created a true artificial intelligence. While that would be awesome, I have my doubts that will actually be the case.
Kurzweil and many others see the singularity by 2020. But it really doesn't take much intelligence to follow directions.
TheGhostofOtto1923
1 / 5 (5) Feb 04, 2013
"In September 2010, the first robotic operation at the femoral vasculature was performed at the University Medical Centre Ljubljana by a team led by Borut Geršak. The robot used was the first true robot, meaning it was not simply mirroring the movement of human hands, but was guided by pressing on buttons."
TheGhostofOtto1923
1 / 5 (5) Feb 04, 2013
Look what clumsy humans can do that computer control will be able to do in real time:
http://www.youtub...N0ej9P8E