DRAG TO ROTATE · SCROLL TO ZOOM
These are your professor's cortical surfaces, reconstructed by FreeSurfer from a 0.75 mm MP2RAGE scan (lightly simplified for the browser). Drag to rotate, scroll to zoom. The folded ↔ inflated slider is the key teaching move: inflation unfolds the sulci so you can see the two-thirds of cortex hidden inside them. In Sulci paint, dark gray = inside a sulcus, light gray = the crown of a gyrus.
Precision controls: the arrow pad (and keyboard arrows, with [ and ] for roll) rotates in precise 1° steps. Hold a button for smooth continuous rotation, hold Shift for 5° steps. The ◎ button snaps to the nearest canonical view.
Compass & orientation practice: the edge labels name the anatomical directions as you rotate (dorsal, ventral, anterior, posterior, left, right), and the line at the bottom names the surface you're facing (including medial vs. lateral when one hemisphere is hidden). Orientation practice quizzes the vocabulary two ways: rotate-to-a-named-view (including medial views, which require hiding a hemisphere), and name-the-view-you're-shown (the compass hides during questions: no cheating).
Atlases: paint the surface with Lobes (the big picture), Desikan–Killiany (34 gyral regions), Destrieux (74 regions with sulci named as structures), or Functional component (FEF, TPJ, dACC, mPFC and friends, from intersecting the Yeo 7 networks with this brain's parcellation). Hovering names whatever is under the pointer using the selected atlas. "Filter labels…" limits the paint to any subset. Everything else falls back to sulci-gray, so a single region can be spotlighted at any stage of the unfold, flatmap included.
Find-the-structure quiz (GeoGuessr rules): ten regions drawn from the selected label category, 100 points each. Click the surface to drop a yellow guess pin (click again to move it), then Submit guess. The score falls off with the distance from your pin to the nearest edge of the true region, measured in millimeters along the cortical sheet (the walking distance across the folded surface at any unfold stage, not the shortcut through space). After each guess both your pin and the true region stay on the brain, and you can rotate, unfold, and inspect freely before pressing Next trial. The paint row is your difficulty setting: with Labels painted you can read the map; in Clay or Sulci you're navigating from anatomy alone and your score lands on the separate blind-mode leaderboard. Pointer naming pauses during the quiz. Scores post to the shared class leaderboard, kept separately per category and mode; when offline they stay on your device.
Flattening: the sheet is cut around the medial wall (where the cortex attaches beneath the corpus callosum) and unfolded with FreeSurfer's mris_flatten, the exact tool behind the Gallant lab's pycortex flatmaps, run on this very brain, plus a brief rigidity-preserving cleanup pass. Some distortion is unavoidable (you can't flatten a curved sheet perfectly: ask any mapmaker). Spread out, this cortex covers ≈1,680 cm².