Amazing stuff! This may also explain or support the enormous plasticity of the brain e.g. after brain injury etc.
Given the many and very varied topics on my blog, I must have tons of jack-of-all-trades neurons in my brain or are these curiosity neurons! Just kidding! 😊
"... The new research focuses on a mystery as old as neuroscience. Is each neuron in the brain a specialist devoted to a limited task, like a hammer or a saw, or do they tend to be generalists, jacks-of-all-trades like Swiss Army Knives? ...
that specialist neurons certainly do exist, but the majority appear to be generalists. ...
These new findings shed light on how the brain may ultimately prove capable of performing complex tasks. ...
Previous research found the brain is organized into modules devoted to vision and smell and other processes; so perhaps such specialization might extend all the way down to the level of neurons. On the other hand, the brain is an incredibly powerful general-purpose computer that can respond in an extraordinary number of ways to a huge variety of situations, so maybe its neurons are similarly generalist in nature. ...
To help resolve the debate, in the new study, the researchers developed a strategy where they looked only at mice, across many brain areas at once as the rodents all performed the same type of activity. This involved analyzing datasets much larger than typically studied, recordings of lots of neurons from the International Brain Laboratory consortium of activity in 43 regions across the mouse cortex on the level of single neurons.
In primary sensory areas, such as the brain region devoted to vision, neurons behaved in specialized ways. However, elsewhere, neurons generated far more diverse responses. In other words, when it comes to the question of whether neurons are typically specialists or generalists, these new findings suggest the latter holds true. ..."
From the abstract:
"A long-standing debate in neuroscience concerns whether individual neurons are organized into functionally distinct populations that encode information differently (categorical representations and the implications for neural computation.
Here we systematically analysed how cortical neurons encode cognitive, sensory and movement variables across 43 cortical regions during a complex task (14,000+ units from the International Brain Laboratory public Brainwide Map dataset) and studied how these properties change across the sensory–cognitive cortical hierarchy.
We found that the structure of the neural code was scale dependent.
At the whole-cortex scale, neural selectivity was categorical and organized across regions in a way that reflected their anatomical connectivity.
However, within individual regions, categorical representations were rare and limited to primary sensory areas, and neuronal responses were instead very diverse.
With theoretical arguments and empirical evidence, we demonstrate that the diversity of neural responses enables high-dimensional representations and therefore high separability, allowing linear readouts to separate experimental conditions in many arbitrary ways.
Indeed, when accounting for information that is actually encoded in each area, all cortical regions exhibit maximal separability.
Our results indicate that cortical circuits prioritize diversity over categorical structure, supporting a computational regime geared towards high-dimensional, highly separable neural representations."
Upending Decades of Debate, Scientists Discover Most Neurons are Jacks-of-All-Trades | Columbia | Zuckerman Institute "Findings that neurons in mice are mostly generalists, instead of specialized for specific functions, has scientific community abuzz"
Fig. 1: Conceptual framework and data structure.
Fig. 2: Large-scale functional organization of the cortex.
Fig. 4: A unified measure of response profile diversity.
Extended Data Fig. 7: A globally organized brain, with functional clustering closely reflecting anatomical structure.
