(True Creatives/Canva)
When you recognize a familiar face, your brain must connect that face with a name, a place, and perhaps a memory.
Those pieces of information are not necessarily handled in the same part of the brain. Yet they come together so smoothly that you experience them as a single thought.
Scientists may now have found one way the brain pulls off this trick.
A new study suggests that distant parts of the brain briefly fall into the same rhythm when we hold and retrieve information. During these fleeting moments, their cells become more likely to send signals together, potentially allowing separate pieces of a thought to be joined.
Published in Nature Neuroscience and led by medical scientist Ilya Verzhbinsky and neuroscientist Eric Halgren of the University of California San Diego, the new research examined brain recordings from 35 people being monitored for treatment-resistant epilepsy.
"'Firing together' may be the brain's basic currency for linking information."
– Medical scientist Ilya Verzhbinsky
These patients already had electrodes placed inside their brains for medical reasons. This gave the researchers a rare opportunity to listen to the electrical activity of individual brain cells while the participants completed a memory test.
They were shown either one or three images and asked to remember them for a few seconds. They then had to decide whether another image had been part of the original group.
Synchronized ripple oscillations may support communication between distant brain regions during working memory.
(Ilya Verzhbinsky, created with assistance from Google Gemini)
The researchers were especially interested in extremely brief bursts of electrical activity called ripples.
"A ripple is a very brief burst of rhythmic oscillations in neuron excitability – roughly 90 cycles per second, lasting only about a tenth of a second," Verzhbinsky told ScienceAlert.
In simpler terms, a small group of brain cells suddenly becomes highly active and moves to the same fast beat. The entire event is over almost as soon as it begins.
Across 43 recording sessions, the researchers followed the activity of 1,373 brain cells. They discovered that ripples often appeared at the same time in two distant brain regions.
When that happened, cells in those regions were about 30 percent more likely to send signals together. In some parts of the task, the increase reached 49 percent.
This may help explain how information stored across the brain can be combined into one experience.
A face may be processed in one area, a name in another, and the place where you met that person somewhere else. The shared rhythm could briefly open a line of communication between those areas, allowing them to work as one team.
"That matters because 'firing together' may be the brain's basic currency for linking information," Verzhbinsky said.
The most surprising result was how far this coordination reached. The shared ripples linked areas separated by as much as 220 millimeters and even appeared across the brain's two halves.
Ordinarily, direct connections between brain regions become less common as the distance between them increases. If the ripples depended only on direct wiring, their coordination should have weakened over longer distances. It did not.
The results suggest this coordination may not require a single brain region acting as a conductor. Instead, the effect may resemble a crowd gradually beginning to clap to the same beat without anyone directing it.
The rhythm also became more prominent when the memory task grew harder. When participants remembered three images rather than one, coordinated signaling rose by about 13 percent while they held the images in mind and by 19 percent when they tried to recognize one.
Cells that sent signals together when an image was first seen were also more likely to repeat that pattern when the same image appeared again. Participants tended to recognize the image faster when this happened.
Previous research has connected similar ripples with the replay and storage of memories. One recent study covered by ScienceAlert found that even one exercise session could change memory-related ripples in the human brain.
The new findings suggest these brief rhythms may also help the brain keep a thought together while we are actively using it.
But the study does not prove that the ripples caused faster recognition. The researchers observed the signals but did not turn them on or off to see how memory changed.
All participants also had severe epilepsy, and the electrodes were positioned according to their medical needs. That meant only selected parts of their brains could be studied. The experiment tested just one type of memory task.
Verzhbinsky said it would be premature to consider these signals a target for treating conditions that affect memory or thinking. Researchers first need to find out whether the same activity occurs in healthy brains and whether disrupting it changes memory.
For now, the results offer a compelling possibility: A thought may feel whole because distant parts of the brain briefly find the same beat.
The Life of Earth
https://chuckincardinal.blogspot.com/
no mention of entanglement, seems the idea never crossed their minds, lol
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