A team of MIT engineers and neuroscientists has unveiled a groundbreaking microscopy system that could drastically enhance our understanding of the brain's synaptic activity. This cutting-edge technology, known as "multiline orthogonal scanning temporal focusing" or mosTF, promises to bring unparalleled clarity and speed to the imaging of synapses, the vital connections through which neurons communicate, as reported by MIT News.
The quest to grasp the brain's plasticity—the adaptability of neurons to form ever-changing circuits—has long faced the impediment of sluggish imaging tools unable to keep up with the rapid alterations in circuitry. The mosTF system aims to overcome this barrier, being capable of imaging a living brain's synapses with a scanning mechanism that's reported to be eight times faster than the traditional two-photon microscopy method. What makes this technology truly stand out is its ability to significantly reduce scan time without compromising resolution.
Elly Nedivi, a key collaborator in the research and a neuroscience professor at MIT, emphasized the limitations of previous methods, noting, "Tracking rapid changes in circuit structure in the context of the living brain remains a challenge." Nedivi highlighted that the mosTF system combats the inherent light scattering within brain tissue—a notorious issue for imaging techniques—by cleverly reassigning scattered photons back to their original location, according to MIT News. This advanced approach not only speeds up the process but also delivers much clearer images.
Lead author Yi Xue, an assistant professor at the University of California at Davis and MIT alumni, acknowledges that while the mosTF system operates by scanning with lines of light rather than point by point, the real advantage lies in the two-dimensional reconstruction potential. To clearly visualize the complex environment of a living brain, the mosTF scope manages to achieve a four-fold better signal-to-background ratio compared to other modes of imaging, proving it to more effectively reveal the intricate details of neuron spines and dendrites. “Our excitation light is a line, rather than a point — more like a light tube than a light bulb — but the reconstruction process can only reassign photons to the excitation line and cannot handle scattering within the line," Xue elucidated, as reported by MIT News.
Peter T.C. So, professor of mechanical engineering and biological engineering at MIT and one of the project's leaders, is not resting on current achievements. He is already planning further enhancements to the system, aiming to develop a next-generation microscope that utilizes highly sensitive and fast detectors, such as hybrid photomultiplier or avalanche photodiode arrays. The research, spanning collaboration across disciplines and institutions, has received support from several esteemed bodies, including the National Institutes of Health and The JPB Foundation.
