SEP 10, 2019 3:06 PM PDT

Neuroscientists create a stunning digital map of 1,000 neurons

Two years ago, Dr. Jayaram Chandrashekar and his colleagues at the Howard Hughes Medical Institute’s Janelia Research Campus sought out to map the mouse brain as intricately as possible. Now, they have unraveled more than 1,000 neurons by tracing each cell’s branch (called an axon) all the way to the next cells in line that these cells connect to. If laid end to end, neurons would stretch more than 85 meters – nearly the length of a soccer field, the team reports in the journal Cell.

When researchers began their brain mapping project, neuroscientists had a general idea of how each brain region was connected, but the actual structure of neural pathways remained unknown. A detailed picture of the neural circuits in a rodent brain can help scientists better understand how to brain is wired, and inform how different types of cells communicate with one another. In 2017, the neuron-tracing project, called MouseLight, mapped the first 300 neurons. Now, they’ve added another 700 cells.

“It’s by far the largest digital collection of such neurons,” says Chandrashekar.

Researches use the latest neural tracing technology to map cells. First, they inject a virus that can target specific cells to make them light up. Next, a fluorescence microscope is used to make these cells glow, and high-resolution images of the stunning neurons are captured. A computer program then stitches nearly 20,000 images together to make a 3-D map of the brain. These tools are powerful and fast – currently, it only takes one day to trace a single neuron. A few years ago, it took over a week.

"It's like putting together 20,000 Lego blocks," Chandrashekar says.

A high-resolution image of neurons sending long-range axonal branches across the mouse brain.

Photo credit: MouseLight/ Janelia Research Campus

Despite advances in brain mapping, much of the mouse brain – which contains about 70,000 neurons – is uncharted territory. Dr. Karl Svoboda, group leader at Janelia, estimates that you’d need to trace 100,000 neurons to get even a crude view of an entire brain map.

The MouseLight team has focused on a few key brain areas: the motor cortex, the hypothalamus, and the thalamus, to name a few. They even found previously unidentified types of cells within these brain regions based on the shape of the cells’ branches. The project is moving forward quickly, and the team has shared their impressive dataset online so that other scientists can benefit from and join their neural cartography effort.

Source: ScienceDaily, HHMI News

About the Author
You May Also Like
SEP 21, 2020
Neuroscience
Scientists Compare Structural and Functional Evolution with First Atlas of Cavefish Brains
SEP 21, 2020
Scientists Compare Structural and Functional Evolution with First Atlas of Cavefish Brains
Cavefish are fish that dwell in caves, unable to access the outside world. Often, they were separated from their closest ...
SEP 24, 2020
Health & Medicine
Extreme Isolation can Cause Physical Brain Changes
SEP 24, 2020
Extreme Isolation can Cause Physical Brain Changes
By this point in the year, you’ve either heard or uttered the phrase “quarantine brain.” While the act ...
OCT 22, 2020
Cannabis Sciences
Cannabis Reduces OCD Symptoms by 50%
OCT 22, 2020
Cannabis Reduces OCD Symptoms by 50%
Researchers from Washington State University have found that smoking cannabis can lead to a short term reduction in up t ...
NOV 08, 2020
Cannabis Sciences
Can Cannabis Treat Epilepsy?
NOV 08, 2020
Can Cannabis Treat Epilepsy?
There has been growing interest in recent years for cannabis to treat central nervous system disorders. And so far, ther ...
NOV 24, 2020
Neuroscience
Could Memory Manipulation Treat Alcohol Addiction?
NOV 24, 2020
Could Memory Manipulation Treat Alcohol Addiction?
Researchers from Boston University have found that manipulating how fear-based memories are processed may modify addicti ...
NOV 29, 2020
Genetics & Genomics
Gene Therapy for Eye Disorder May Have Other Applications
NOV 29, 2020
Gene Therapy for Eye Disorder May Have Other Applications
In recent years, scientists have been able to develop gene therapies to treat some eye diseases. The eyes are uniquely q ...
Loading Comments...