The mouse brain is clearer than ever

Image: An MRI image of a mouse brain has a resolution of just five micrometres.

American scientists have succeeded in creating an MRI device that is more than sixty million times clearer than standard MRI brain scans and a thousand times more detailed than the best scientific MRI images. They used a CT scan with a 9.4 Tesla magnet, which is three times stronger than the magnets of clinical devices. Other technical advantages include: a special array of gradient coils that are 100 times more powerful than those in conventional MRI machines, and a powerful computer to process the huge amount of data. Use Diffusion tensor imaging (DTI), they also tracked the movement of water molecules in tissues and were able to map the path of nerve fibers.

However, the resulting MRI images do not have the resolution that microscopes can achieve. So the researchers also examined brain tissue using light microscopy, a relatively new method with high resolution. This allowed them to distinguish between different types of cells with an accuracy of up to 1.8 micrometres. They then correlated these images with MRI images. The result is a 3D image of a mouse's neural connections.

Research has already provided preliminary answers. For example, when asked what happens in a mouse brain as it ages: The decline appears to mainly affect the subiculum, the part of the hippocampus that is involved in long-term memory.