Some disorders of the brain are obvious — the massive death of brain cells after a stroke, the explosion in the growth of cells that marks a tumor. Other disorders, such as autism, schizophrenia and mental retardation show no physical signs of damage and are believed to be caused by problems in how brain cells communicate with one another.

To understand the root of the problem of these latter diseases, visualizing brain activity is key. But even the best imaging devices available — fMRIs and PET scans — can only give a "coarse" picture of brain activity.

UCLA neuroscientists have now collaborated with physicists to develop a non-invasive, ultra–high-speed microscope that can record in real time the firing of thousands of individual neurons in the brain as they communicate, or miscommunicate, with each other.

"In our view, this is the world's fastest two-photon excitation microscope for three-dimensional imaging in vivo," said UCLA physics professor Katsushi Arisaka, who designed the new optical imaging system with UCLA assistant professor of neurology and neurobiology Dr. Carlos Portera-Cailliau and colleagues.

Their research appears in the Jan. 9 edition of the journal Nature Methods.

Neuronal activity seen with UCLA STEM microscope

The roundish profiles that sometimes blink are brain cells in the cerebral cortex that have been stained with a special fluorescent dye that senses calcium inside the cell. As brain cells fire electrical signals to communicate with each other, the calcium increases inside them, so the fluorescent dye allows us to ‘see’ the activity of brain cells.

(Video credit: UCLA)

Source Article : New UCLA-designed microscope records firing of thousands of individual neurons in 3-D