Allen Institute's 'Microns' Project Creates Detailed Brain Circuit Map of Mouse Visual Cortex

Researchers at the Allen Institute have created a highly detailed circuit map of a cubic millimeter of a mouse's visual cortex through the 'Microns' project. This map details the connections between 75,000 neurons and includes over 200,000 cells, 84,000 neurons, 524 million synaptic connections, and several kilometers of axons. The study, published in *Nature*, involved recording neuronal activity while the mouse watched videos. Subsequently, the brain was sliced into 28,000 ultra-thin sections for high-resolution imaging and 3D reconstruction using AI. This comprehensive map offers new insights into brain organization, including a principle of inhibition where inhibitory cells selectively target other cells in a coordinated manner. Scientists believe this resource will aid in understanding brain disorders such as Alzheimer's and autism by comparing healthy and diseased brain wiring.