Mapping the human brain without distortions
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.
Researchers now solved the problem by using a technique that rapidly freezes the brain, preserving its true structure. 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.
Source: Graham Knott, Natalya Korogod and Carl Petersen, Swiss Federal Institute of Technology in Lausanne
