The Black-capped Chickadee seen here is well known for its strong episodic memory.Dmitri Aronov Hide Caption
Toggle caption Dmitri Aronov
The Black-capped Chickadee seen here is well known for its strong episodic memory.
Dmitri Aronov
The little black-capped tit has great memories. They hide food in hundreds to thousands of different locations in the wild and return to these caches when other food sources become scarce. Now, researchers at Columbia University's Zuckerman Institute believe that this impressive feat may be due to a unique pattern of neural activity that acts like a barcode. Their research was recently published in the journal Cell.
Scientists know that galas have amazing memories. That memory can be a matter of life or death for these birds, as food sources diminish during the cold season.
The hippocampus is important in forming this type of memory. Colin Saldaña, a songbird researcher and neuroscientist at American University who was not connected to the study, said the hippocampus in these birds' brains collects and stores seeds each fall, so It is also said to have expanded in the brains of seagulls. Saldaña was not connected to the study.
“These animals exhibit levels of brain plasticity that are comparable to those of us humans,” he says.
Unique brain activity for various memories
Some researchers thought that neurons called “place cells” could explain these birds' ability to remember food caches. These cells are known to encode information about where objects are in space. But recently, a team of researchers discovered that each time a black-capped tit hides a seed in a specific location, unique brain patterns appear in the hippocampus, separate from place cells. Selman Chetty compared it to a barcode.
“The hippocampus has kind of reversed its state,” Chetty says. “It was like a switch was flipped, and now there was a whole new pattern of activity that was completely different from place cells.”
To observe this, Chetty and his team built an arena with a feeder containing sunflower seeds in the corner. Wooden perches for birds were scattered throughout, with little flaps where birds could hide seeds.
The researchers inserted small probes into the seagulls' brains and tracked activity in the hippocampus. Every time a bird hid a seed under its wing flaps, the researchers observed a short, unique brain pattern, called a “barcode,” appear. Each pattern was specific to the case of seed hiding, and different patterns emerged even when birds hid multiple seeds in the same location or when they made caches on adjacent perches.
When the bird revisits these locations and retrieves the hidden seeds, the same barcode-like pattern appears again, as if all the information about each location and seed was associated with a unique brain pattern. It appeared.
Our memories define us. But what do they look like?
The researchers compared these memories to human episodic memory, which is the memory of specific events or personal experiences. They are integral to the way humans define themselves and connect moments of time, people, places, and sensory information. However, the mechanism of how this binding occurs is still unclear.
Chetti says it's incredibly difficult to know exactly when animals are forming memories. Therefore, the fact that this seed-hiding behavior has a distinct pattern of activity associated with it could help researchers build a framework for how the brain creates and stores memories. .
Professor Saldaña said this is what makes the study “truly heroic”. This will allow researchers to observe the process by which memories are created in the brain. “They rely mostly on the animals' own talents to understand the neural basis of this amazing behavior,” he says.
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Today's episode was produced by Berly McCoy and Vincent Acovino. Edited by Rebecca Ramirez, Viet Le, and Christopher Intagliata. Rachel Carlson, Rebecca and Regina G. Barber fact-checked. Valentina Rodriguez-Sanchez and Patrick Murray were the audio engineers.
