A massive suite of papers offers a high-res view of the human and non-human primate brain.<\/p>\n
By Cassandra Willyard
\nOctober 12, 2023<\/p>\n
This article first appeared in The Checkup, MIT Technology Review\u2019s weekly biotech newsletter. To receive it in your inbox every Thursday, and read articles like this first, sign up here.<\/p>\n
When scientists first looked at brain tissue under a microscope, they saw an impenetrable and jumbled mess. Santiago Ramon y Cajal, the father of modern neuroscience, likened the experience to walking into a forest with a hundred billion trees, \u201clooking each day at blurry pieces of a few of those trees entangled with one another, and, after a few years of this, trying to write an illustrated field guide to the forest,\u201d according to the authors of The Beautiful Brain, a book about Cajal\u2019s work.<\/p>\n
Today, scientists have a first draft of that guide. In a set of 21 new papers published across three journals, the teams report that they\u2019ve developed large-scale whole-brain cell atlases for humans and non-human primates. This work, part of the National Institutes of Health BRAIN Initiative, is the culmination of five years of research. \u201cIt\u2019s not just an atlas,\u201d says Ed Lein, a neuroscientist at the Allen Institute for Brain Science and one of the lead authors. \u201cIt\u2019s really opening up a whole new field, where you can now look with extremely high cellular resolution in brains of species where this typically hasn\u2019t been possible in the past.\u201d<\/p>\n
Welcome back to The Checkup. Let\u2019s talk brains.<\/p>\n
What is a brain atlas, and what makes this one different?<\/p>\n
A brain atlas is a 3-D map of the brain. Some brain atlases already exist, but this new suite of papers provides unprecedented resolution of the whole brain for humans and non-human primates. The human brain atlas includes the location and function of more than 3,000 cell types in adult and developing individuals. \u201cThis is far and away the most complete description of the human brain at this kind of level, and the first description in many brain regions,\u201d Lein says. But it\u2019s still a first draft.<\/p>\n