Brain atlas

(Top left, top right, bottom left) Coronal, sagittal and axial MRI slices through a brain, with colours indicating different anatomical regions. This labeling process turns the brain images into a brain atlas. (Bottom right) Correspondence between brain atlases: 3D Rendering of three anatomical regions in the left temporal lobe as delineated by two different brain atlases. The largest region, labeled Superior Temporal in one atlas, shown in yellow, overlaps both the Superior Temporal Gyrus (blue) and the Middle Temporal Gyrus (red) regions in another atlas (the same as in the previous images) to differing degrees. From Bohland et al., 2009.

A brain atlas is an anatomical atlas of the brain, i.e. a reference work in which brain structures are placed in a coordinate system that is standardized for a given species or developmental stage. Several neuroimaging techniques can be used to obtain the images for brain atlas construction, e.g. from histology or — increasingly common — from MRI scans of one or many or entire brains or cerebral hemispheres.

Apart from providing a common coordinate system for imaging data obtained from different sources (e.g. from a number of patients), brain atlases can be partitioned and labeled, thus providing for atlas-based segmentation of images and for the construction of brain maps. Much like geographic maps can be populated with information about physical, political, economic or environmental aspects of a region of interest, brain maps may include information about genetic, developmental, evolutionary or physiological or pathological aspects of the brain.