Per a piece by Carl Zimmer, we know that there are, at a minimum, more than 3,000 different types of cells in the human brain. This is reinforcement for what I said years ago: That neuroscience, and related science and science-philosophy fields like cognitive science are still in the Stone Age. We maybe Neolithic rather than Paleolithic now, but still the Stone Age. Here's the biggie further reinforcing that:
The researchers found many new types of neurons, cells that use electric signals and chemicals to process information. But neurons make up only about half the cells in the brain. The other half are far more mysterious.
Astrocytes, for example, appear to nurture neurons so that they can keep working properly. Microglia serve as immune cells, attacking foreign invaders and pruning some of the branches on neurons to improve their signaling. And the researchers found many new types of these cells as well.
We just don't know what these cells do. And, we don't know how they interact with each other.
So, there's all this to ponder and study:
Megan Carey, a neuroscientist at the Champalimaud Center for the Unknown in Portugal who was not part of the brain atlas project, said that the research provided a staggering amount of new data for researchers to use in future studies. “I think this is a tremendous success story,” she said.
Yet she also cautioned that understanding how the human brain works would not be a matter of simply cataloging each and every part down to its finest details. Neuroscientists will also have to step back and look at the brain as a self-regulating system.
“There will be answers in this data set that will help us get closer to that,” Dr. Carey said. “We just don’t know which ones they are yet.”
Adam Hantman, a neuroscientist at the University of North Carolina who was not involved in the study, said that the atlas would be a big help for some kinds of research, like tracing the development of the brain. But he questioned whether a catalog of cell types would elucidate complex behavior.
“We want to know what the orchestra is doing,” he said. “We don’t really care what this one violinist is doing at this one moment.”
There you go.