Scientists on theNeural Dynamics team at Allen Institute are building a 3D model of the brain by assembling 2D images produced via light-sheet microscopy. Light-sheet microscopy is a high-speed imaging technique that uses a thin “sheet” of light to capture high-resolution 2D images of a fluorescently stained specimen. Unlike traditional microscopes that scan a sample pixel by pixel to form a 2D image over time, light-sheet methods capture millions of pixels all at once to rapidly form 2D images. When these 2D sections are stitched together, they produce a comprehensive 3D model that allows scientists to examine biological structures in greater detail. A vast map of neural connections within a mouse brain is spotlighted above in a microscopy image captured at the University of Washington by Adam Glaser, Ph.D., now a Senior Scientist at the Allen Institute. Understanding this network is key to learning how the brain drives behavior and decision-making. Glaser and his colleagues are working on the development of tools for large-scale imaging projects. They are currently building three customized light-sheet microscopes and plan to use them to identify and describe different neuronal cell types and their connections.