Researchers image most of vertebrae brain at single cell level (w/ video)

March 20, 2013 by Bob Yirka report
Whole-brain imaging of neuronal activity with cellular resolution. Credit: Nature Methods (2013) doi:10.1038/nmeth.2434

(Medical Xpress)—Misha Ahrens and Philipp Keller, researchers with the Howard Hughes Medical Institute have succeeded in making a near real-time video of most of a zebrafish's brain showing individual neuron cells firing. To create the video, as the team reports in their paper published in the journal Nature Methods, the two developed a type of modified light-sheet microscopy and used it in on genetically modified fish.

To create the video, the researchers turned to in their larval state—their brains are transparent and small. To cause firing neurons to be visible they genetically altered the fish's brains, giving them a protein that glows when responding to changes in calcium ion levels, which happen when fire. Next, they used a microscope that was able to broadcast a sheet of light through the fish's brain allowing for the detection of the firing neurons. The system recorded images every 1.3 seconds. The final step was stitching the images together to create a video. The result is nothing short of breathtaking—looking like something out of a science fiction movie's special effects department.

The video will load shortly.
Fast volumetric imaging of the zebrafish brain with light-sheet microscopy. Credit: Nature Methods (2013) doi:10.1038/nmeth.2434

The video marks the first visual capture of most of a living brain at the neuron level, as it works in near real-time and offers striking evidence of the complexity of the brain—even one as small as 100,000 neurons. The researchers say their video shows approximately 80 percent of the zebrafish's brain as it operates—though what all those firing neurons represent in particular, is still unknown.

The researchers are careful to point out that what they've accomplished does not portend the creation of a video of a in action—our brains are much larger, have billions more neurons and perhaps more importantly, are not transparent and are covered by a thick skull. Instead they suggest that studying a simpler in action might help to explain how biological neural networks actually work, perhaps leading to theories that can be generalized over larger animals.

The video will load shortly.
Whole-brain imaging of neuronal activity. Credit: Nature Methods (2013) doi:10.1038/nmeth.2434

The video will load shortly.
Neuronal activity in the forebrain. Credit: Nature Methods (2013) doi:10.1038/nmeth.2434
But before that can happen, the procedure the team has developed needs to be improved— can fire at hundreds of times per second, which means a lot of firing in the video has been missed. Capturing at a faster rate would mean generating nearly unmanageable amounts of data—at the current rate, just one hour of capture creates a terabyte of data. Thus a new way to store and process the data must be developed.

Explore further: Virtual reality allows researchers to measure brain activity during behavior at unprecedented resolution

More information: Whole-brain functional imaging at cellular resolution using light-sheet microscopy, Nature Methods (2013) doi:10.1038/nmeth.2434

Abstract
Brain function relies on communication between large populations of neurons across multiple brain areas, a full understanding of which would require knowledge of the time-varying activity of all neurons in the central nervous system. Here we use light-sheet microscopy to record activity, reported through the genetically encoded calcium indicator GCaMP5G, from the entire volume of the brain of the larval zebrafish in vivo at 0.8 Hz, capturing more than 80% of all neurons at single-cell resolution. Demonstrating how this technique can be used to reveal functionally defined circuits across the brain, we identify two populations of neurons with correlated activity patterns. One circuit consists of hindbrain neurons functionally coupled to spinal cord neuropil. The other consists of an anatomically symmetric population in the anterior hindbrain, with activity in the left and right halves oscillating in antiphase, on a timescale of 20 s, and coupled to equally slow oscillations in the inferior olive.

Related Stories

Virtual reality allows researchers to measure brain activity during behavior at unprecedented resolution

May 9, 2012
Researchers have developed a new technique which allows them to measure brain activity in large populations of nerve cells at the resolution of individual cells. The technique, reported today in the journal Nature, has been ...

Optogenetics researcher develops wireless brain stimulator

June 28, 2011
(Medical Xpress) -- In a major step forward in optogenetics, MIT researcher Christian Wentz has developed a sort of wireless hat that can be used to transmit light to photo sensitized cells in the brain, thus stimulating ...

Research team uses optogenetics to reverse effects of cocaine

December 8, 2011
(Medical Xpress) -- A team of Swiss researchers, led by Christian Lüscher of the University of Geneva, has found the first casual link between cocaine use and physical brain changes and in so doing, as they describe ...

Study shows how neurons interact, could lead to new treatment for addiction

January 18, 2012
Harvard scientists have developed the fullest picture yet of how neurons in the brain interact to reinforce behaviors ranging from learning to drug use, a finding that might open the door to possible breakthroughs in the ...

Study identifies how zebrafish regrow their brains

November 9, 2012
(Medical Xpress)—An international team of scientists has discovered the mechanism by which zebrafish can re-grow brain neurons after they have suffered traumatic brain injury, and that this mechanism is associated with ...

Researchers develop tool for reading the minds of mice (w/ Video)

February 19, 2013
(Medical Xpress)—If you want to read a mouse's mind, it takes some fluorescent protein and a tiny microscope implanted in the rodent's head.

Recommended for you

'Selfish brain' wins out when competing with muscle power, study finds

October 20, 2017
Human brains are expensive - metabolically speaking. It takes lot of energy to run our sophisticated grey matter, and that comes at an evolutionary cost.

Researchers find shifting relationship between flexibility, modularity in the brain

October 19, 2017
A new study by Rice University researchers takes a step toward what they see as key to the advance of neuroscience: a better understanding of the relationship between the brain's flexibility and its modularity.

Want to control your dreams? Here's how

October 19, 2017
New research at the University of Adelaide has found that a specific combination of techniques will increase people's chances of having lucid dreams, in which the dreamer is aware they're dreaming while it's still happening ...

Brain training can improve our understanding of speech in noisy places

October 19, 2017
For many people with hearing challenges, trying to follow a conversation in a crowded restaurant or other noisy venue is a major struggle, even with hearing aids. Now researchers reporting in Current Biology on October 19th ...

Investigating the most common genetic contributor to Parkinson's disease

October 19, 2017
LRRK2 gene mutations are the most common genetic cause of Parkinson's disease (PD), but the normal physiological role of this gene in the brain remains unclear. In a paper published in Neuron, Brigham and Women's Hospital ...

Brain takes seconds to switch modes during tasks

October 19, 2017
The brain rapidly switches between operational modes in response to tasks and what is replayed can predict how well a task will be completed, according to a new UCL study in rats.

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.