Click the brain to identify a region.
Explore a brain parcellation in the browser: view it as slices or on the cortical surface, find and colour regions, drape per-region values as a heatmap, and export publication figures. Everything runs on your machine — no file you open is ever uploaded.
Drag files onto the window, or use Choose files. Two kinds are recognised:
.nii/.nii.gz) or a two-file .hdr+.img pair
(drop both), plus a label table. Tables can be BIDS dseg.tsv, CSV,
FreeSurfer LUT, ITK-SNAP, FSL XML, a Connectome Workbench list, or JSON. A volume
with no table still opens, with regions named by number.
.dlabel.nii or GIFTI
.label.gii. These carry their own colours and names; geometry comes
from bundled fs_LR 32k surfaces, or drop your own .surf.gii to override.
No data of your own? Press Load AAL demo.
Volume shows three orthogonal slices above a 3D render; the toolbar switches layout, atlas opacity, the anatomical template, a label offset for tables that are off by one, and a dark or light background — light mode renders the T1 on clean white for publication figures. Surface shows the four-panel figure (left/right × lateral/medial) with inflated or midthickness geometry, a dark or light background, a shared zoom, and angle/size resets.
With a parcellation loaded, use Load region values… (or drop a data file) to colour regions by a per-region number — an activation, a hierarchy level, any measure. The file can be:
name,value — matched by region name;index,value — matched by label value;A colormap is chosen automatically — diverging and centred on zero for signed data, sequential otherwise — and the colourbar under the view shows the value-to-colour mapping. Change the colormap, Reverse it, toggle Centre on 0, or set the range by hand. Clear values returns to the categorical colours.
Save PNG renders at 2–8× the on-screen size — real resolution, not an upscale. In heatmap mode the colourbar is drawn into the image, so the figure is self-contained. For a surface figure, set the background to Light first. The export is raster (PNG); SVG/PDF is not available from the browser.
Source and documentation: github.com/payman21/brain-atlas-explorer.