Researchers at a Swiss institute developed a new technology that can map the human brain in unprecedented detail without distorting the architecture of the brain. The results also showed that our brain may not be as compact as generally thought.
To study the fine structure of the brain - including its connections between neurons and the synapses - scientists generally use electron microscopes.
However, the brain tissue must first be fixed to prepare it for this high magnification imaging method.
This process causes the brain to shrink and as a result, microscope images can be distorted - showing neurons to be much closer than they actually are.
The team from Swiss Federal Institute of Technology in Lausanne have now solved the problem by using a technique that rapidly freezes the brain, preserving its true structure.
The researchers Graham Knott, Natalya Korogod and Carl Petersen successfully used the innovative method called "cryofixation" to prevent brain shrinkage during the preparation for electron microscopy.
The method uses jets of liquid nitrogen to "snap-freeze" brain tissue down to -90 degrees celsius within milliseconds. The brain tissue here was mouse cerebral cortex.
"The high-pressure 'cryofixation' is a very attractive method for brain imaging," Knott said, adding that the results showed our brains may not be as cramped as previously thought.
The team is now aiming to use the technique on other parts of the brain and even other types of tissue. The work was published in the journal eLife