Introducing the brain: concept cells (Introduction)

by David Turell , Tuesday, January 21, 2025, 18:59 (15 hours, 5 minutes ago) @ David Turell

The latest from implanted electrodes:

https://www.quantamagazine.org/concept-cells-help-your-brain-abstract-information-and-b...

"Abstract representations of individuals, objects and ideas are stored in individual brain cells known as concept neurons. Research suggests that they are central to memory.

"when researchers identified concept cells in the early 2000s, the laughter started to fade. Over the past 20 years, they have established that concept cells not only exist but are critical to the way the brain abstracts and stores information. New studies, including one recently published in Nature Communications, have suggested that they may be central to how we form and retrieve memory.

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"Fried and Quiroga collaborated with Koch to investigate. During surgery on consenting epilepsy patients, they inserted electrodes into each patient’s medial temporal lobe, the part of the brain that includes the amygdala, entorhinal cortex and hippocampus, which is the hub for emotion and memory.

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"When the patients couldn’t identify them, he tried showing them photos of more recognizable places and people, including Jennifer Aniston, a star of the hit sitcom Friends.

"To his delight, he found a neuron that responded to the actor. That raised a new question: “Is it responding to this picture of Jennifer Aniston, or is it responding to the concept of ‘Jennifer Aniston’?” he recalled. In a follow-up experiment, he showed patients seven different pictures of Aniston, and found that the same neuron fired for all of the photos — but not for images of other actors or objects. He then started to identify neurons for other famous places and people. He found one that responded only to Halle Berry, and another that fired only for the Leaning Tower of Pisa.

"Quiroga wrote out the name “Oprah Winfrey.” The same neurons that had fired for her picture also fired for her name. That meant that the neurons weren’t responding to features of the picture, such as brightness or color: They were context-independent. They were responding to Oprah as a concept.

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"Concept cells could code for anything and everything, but they are not used for object recognition. They’re too slow for that: These cells fire after a delay of about 300 milliseconds. “It’s unclear why it takes so long,” said Ueli Rutishauser, a neuroscientist at Cedars-Sinai Medical Center in Los Angeles. Rather, these cells seem to dip into a more internal process, forming an abstract representation informed by past experiences and memory.

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"The paper presented his hypothesis that the brain uses concept cells to convert information from the world into memory. The process requires abstraction: extracting relevant information from experience, stripping it of unnecessary detail and storing it. He proposed that concept cells, as abstract representations of ideas such as specific people or objects, might link together to form new associations (like words in a sentence) and serve as building blocks for memories (like a story composed of sentences).

“'This is the skeleton of how we store memories,” Quiroga said.

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"Indeed, in a recent study in Nature Communications, their team found the strongest experimental hints yet that concept cells may link specific objects to locations in our long-term memory. For decades, researchers have studied “place cells,” which store location information in our brains. The study found that the firing patterns of concept cells and place cells correlated with patients’ ability to remember an object’s location. Concept cells are the “what” to our memories, while place cells are the “where,” the authors wrote.

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"It’s possible that these neurons can play different roles and take on different identities based on the task at hand, Buffalo said. When it needs to be a concept cell for Jennifer Aniston, that’s what it is. When it needs to be a place cell to help you navigate toward the martini at the bar, it is a place cell. “That cell is like a Swiss Army knife,” Miller suggested."

Comment: very early tentative research into memory function. Identifying specific neuron function is amazing. Animals must have place neurons but not concept ones I assume.