- Scientists recently published a new map of the human brain.
- The map allows researchers to understand how human brains differ from other animals.
Our brain cells serve as the building blocks of every thought, feeling, and physical action we've ever had — and yet the brain is still our most mysterious organ. Now, scientists may have a new insight into this black box.
On October 12, scientists announced that they have mapped over 3,000 types of brain cells as part of a human brain atlas that was published in 24 different papers across 3 scientific journals.
By creating an atlas of the human brain, scientists can pinpoint the ways in which the human brain differs from other animals — including our closest living relatives, other primates such as chimpanzees. The map will also help researchers understand how the human brain can change over time, how similar one person's brain is to another, and why some people develop conditions like depression and Alzheimer's, The Washington Post reported.
"We really need this kind of information if we're going to understand what makes us unique as humans, or what makes us different as individuals, or how the brain develops," Ed Lein, a senior investigator at the Allen Institute for Brain Science in Seattle who participated in the studies, told NPR.
The brain contains billions of cells
The research was funded by the National Institutes of Health, and began in 2017 as part of the Brain Research through Advancing Innovative Neurotechnologies Initiative Cell Census Network.
Composed of 170 billion cells, including 86 billion neurons, the brain may very well be "the most complex physical object we know of in the universe so far," Henry Greely, a law professor at Stanford University who was previously involved in a council that helped guide the project, told the Washington Post.
In comparison to the brain, human lungs are only known to have about 100 different cell types, Trygve Bakken, a neuroscientist at the Allen institute, told the Washington Post.
Brain cells were collected both from deceased donors and from consenting patients undergoing brain surgery, the New York Times reported, and categorized by gene activity.
The papers include descriptions of cells like microglia, a type of immune cell found in the brain, as well as the bizarre and still poorly understood "splatter" neuron — a type of neuron that looks like a paint splatter.
A brain map could pave the way for better disease treatment
Mapping out the cells in the human brain could make it easier to find treatments for neurological disorders, including Alzheimer's disease, autism and depression, NPR reported.
Many brain disorders are the result of tiny variations in DNA, but it's been unclear how these variations affect individual brain cells.
The BRAIN atlas creates a series of landmarks for potential changes that indicate disease progression.
"You can use this map to understand what actually happens in disease and what kinds of cells might be vulnerable or affected," Lein told NPR.
While this research is a monumental achievement, it's still only the beginning. According to the Washington Post, the NIH has funded over 1,300 projects.
In the future, researchers expect to discover even more types of brain cells, and to better understand the function of the cells that are already documented. They also hope to better understand how different brain cells work together.