Stanford researchers develop mini microscope for brain

A new, portable miniature microscope designed by Stanford researchers, standing at less than three-quarters of an inch tall, promises to expand the field of neuroscience research by recording the neural activity of mice.

Computers can then process the neural activity data into brain imaging data. Details of the microscope’s development were announced in a paper in Nature this month.

This microscope builds off previous work by associate professor of biology and co-author Mark Schnitzer, who focuses on the development of fiber-optic microscopes. In the fiber-optic model, the optical head of the microscope is mounted to the mouse, while a fiber optic cable relays information to an external imaging system.

Though innovative, this predecessor microscope was costly to produce and imposed physical limitations for mice research studies, according to Abbas El Gamal, professor of electrical engineering and co-author of the paper. The rigid nature of fiber optics restricted the mobility of the mouse  –  and hence the nature of the neural data collected.

Weighing 1.9 grams, the new microscope’s main advantage is its portability. To improve mobility, Stanford researchers traded fiber optics for thin wires, similar to those commonly used for hearing aids. The miniature microscope still attaches to the mouse’s head, but now these flexible cables allow the mouse to move while still collecting a stream of neural data.

To improve the imaging technology of the microscope, researchers “piggybacked” off cellphone imaging research. Gamal said this is the same technology that allows individuals to take pictures on their cellphones.

By using existing imaging technology and its mass-produced material components, the group was able to reduce the manufacturing price. Because of this manufacturing capability, Gamal is confident that the microscopes will be “well commercialized” and “widely used” by labs. He stated that the miniature microscope would be used as an “enabler” instead of a research tool.

“This is not a prototype; it’s something that you use. That’s the value of it,” Gamal said.

In neuroscience labs, the microscopes are used in pre-clinical trials on developmental drugs for neural disorders. Researchers can determine the effect of drugs on mice, particularly via image processing, using particular dyes.

From a global perspective, Gamal mentioned that the microscope could potentially be used as a hand-held, diagnostic instrument in developing countries. Both portable and inexpensive, the microscope is an ideal tool for fieldwork applications, such as screening for tuberculosis in places where labs and traditional microscopes are costly to maintain.

Researchers are currently looking ahead, envisioning a wireless version of the microscope, as well as improved depth for field imaging.