Interactive models

A real brain atlas (MNI152 + AAL) with tau spread by Braak stage, click-to-identify regions, 3D and slice views, ROI drawing with volume in mm³, a population tractography (DTI) atlas, your own scan by drag-and-drop, and a built-in guide that explains regions and tools. A tau-PET kinetics simulator uses flortaucipir rate constants measured with arterial sampling (Barret et al. 2017) to show where an SUVR comes from and why it depends on scan timing and blood flow. A voxel-size slider shows partial-volume blur, and notes explain what tractography can and cannot show, with links to MRIQuestions and The Brain from Top to Bottom. It also has a digital-twin layer: the adaptive digital brain pipeline (made-up data) drawn on the atlas, with each person's forecast, 80% error range and planned next scan. Black Box classic is the same model rebuilt in Scratch, with the same views, atlases, tools and twin (download the .sb3 to open or remix it in Scratch or TurboWarp).

A walkable 3D city of the Study atlas: 172 ideas in 11 districts, from mathematics and physics to mind and society. Each building is built as what it is (laws as monuments, processes as moving loops, molecules you can walk around, disorders as figures with their signs). Walk up to one and its roads light up along the streets to every connected idea, with the relation written overhead; boulevards between districts are named after the discovery that joins those fields. A field guide holds every building as a readable page, and the phone gives directions, a quiz and an editor for adding your own roads. Under the Nephron Park district lies a walkable nephron where the floor shows the live medullary gradient, the glass tubule is coloured by osmolality, and particles of water, salts, glucose, urea and drugs leave the tube where they are reabsorbed. Its control desk (intake hopper, hydration lever, glucose dial, ADH and aldosterone valves, drug cabinet) drives a calibrated model checked against textbook values and the Layton 2019 human nephron model, and you can ride along with the filtrate.

The same nephron model as a flat tool: pick a food, drug or test substance and follow it along the nephron in a 1D profile, see the whole nephron in cortex and medulla in 2D, or read every value in a table, with hydration, glucose, ADH, aldosterone and seven drugs to change. Each segment opens a field-guide page.