It is the first brain of a baby
When lens-sized clusters of nerve cells grow in a lab shell, they begin to fire rhythmic electrical signals. These oscillations have some similarities with those in the brain of developing human babies, researchers report on October 3 in Cell Stem Cell .
Three-dimensional spheres of
Human brain cells, called cerebral organoids, are extremely simplified models
of the human brain. However, these easy-to-obtain organoids may be a better way
to investigate how a brain is made and how this process can go awry ( SN: 2/20/18 ).
"The field is incandescent" with
rapid progress in the production and understanding of brain organoids, says John Huguenard,
a neuroscientist at Stanford University who was not involved in the study.
Coordinated electrical activity in nerve cells or neurons of organoids
First he says. "The neurons grow up there and mature enough there
Not only can you start behaving like neurons and firing individually, but now as well
they can be coordinated.
The study attracted researchers
Stem cells make up some of the neurons that make up the outer layer of the
Brain. These cortical organoids grew in lab shells containing arrays of organoids
Electrodes printed along the bottom allow scientists to monitor
electrical activity in the development of the organoids.
After two months, the
Electrodes began to pick up neural waves or collective behavior that is coming
of many neurons firing signals in tandem. With four to six months is the
The electrical activity in the laboratory-grown cells had reached a level never seen before
before, "says co-author Alysson Muotri, neuroscientist at the University of
California, San Diego. These signals indicate that neurons were in the organoids
Billions of connections are made, he says.
After nine months was the
Organoids showed electrical activity that reflected brain activity
Newborn babies. Mathematical models suggest that "the organoid develops
Just as the human baby brain would do, and it reaches levels that are similar to those
A newborn is nine months old, "says Muotri.
Although the organoids can do this
For some years, their electrical activity plateaus have been living around in the laboratory
Nine months, says Muotri. Further refinements would be required for the organoids
develop more completely.
These organoids, each with a
Millions of times smaller than a human brain, it lacks the complex combination of cells
this helps to shape neuronal waves in humans. Explore Muotri and his colleagues
Ways to increase complexity, possibly by adding more cell types or a
Blood supply. And the scientists stimulate the organoids and deliver
Signals similar to those that neurons could receive from other brain regions, or
the outside world – forces known to shape the growing brain.
The research "delivers one
Initial framework for analyzing how these neural networks form, "says Dr.
neuroscientist Mark Hester from the Nationwide Children's Hospital in Columbus, Ohio,
His work also includes electrical signals generated by the maturation of organoids in the brain.
However, it is important to remember that these organoids are not
but only one model, he says. "It is not a miniaturized brain that we are looking for