EXPLORE A WORLD Brain & Senses Signals, perception, memory, and the world inside your head.
Try a question: How do bicycles work? How does skin feel touch? Why do ships float?
CollectionAll collections How do we know? From silicon to a decision From heat to electricity Structures that carry us Matter under the magnifier Messages inside cells From light to motion How you sense the world Open up the everyday Eleven new ways to wonder Make it move A living world, connected The invisible engineering of everyday life Earth, sky and deep time Inside everyday wonders The body, connected Small actions. Surprising effects. Big ideaAll ideas Information & codes Pressure & fluids Energy & change Waves Cause & effect Systems Forces & motion Structure & function TagAll tags #AI #CMOS #CPU #P-waves #RISC-V #S-waves #TCP #UDP #absorption #acids #action-potential #airflow #anatomy #antibodies #antigen #arithmetic #assembly #astronomy #atmosphere #atoms #attention #bases #batteries #bias #bicycle #binary #biomechanics #black holes #blood #boats #body-clock #boiling #brain #braking #breathing #bridges #buffers #buoyancy #camera #capacitance #carbon #cars #causation #cells #charging #chloroplasts #circadian-rhythm #circuits #circulation #classification #climate #combustion #compression #compressors #computers #conduction #confounding #conservation #cooling #correlation #crankshaft #current #data #deep-time #density #design-history #diaphragm #differential #digestion #dilution #displacement #distribution #dna #ear #earth #earthquakes #eclipses #electricity #electronics #electrons #elements #energy-budget #energy-conservation #engines #enthalpy #epicenter #equilibrium #escape-speed #evaluation #evidence #experiments #eyes #filtration #flight #fluids #focus #food #free-fall #frequency #friction #gas-exchange #gears #genetic-code #geology #gravity #greenhouse-effect #hearing #heart #heat #heat-pumps #heat-transfer #heating #homes #hydraulics #ice #immune-memory #immune-system #infection #infrared #insulation #internet #intestines #ion-channels #ions #isotopes #jet-lag #joints #kepler #kidneys #language models #latent-heat #lenses #lensing #leverage #levers #lift #lifting #light #lithium-ion #logarithms #logic #lungs #lymph #machine learning #magnetism #mass #materials #mechanical-advantage #melting #memory #microwaves #momentum #moon #motors #mrna #muscles #nephron #nerves #networks #neurons #nuclear-fission #nutrients #optics #orbits #overfitting #oxygen #pH #packets #phases #photosynthesis #photovoltaics #pistons #plants #plates #power #pressure #probability #processors #programming #propulsion #proteins #public-health #pulleys #quantum #randomization #randomness #reabsorption #reactors #refrigeration #relativity #renewable-energy #resistance #retina #ribosome #rna #rockets #sampling #satellites #seafloor #secretion #seismic-waves #seismology #semiconductors #silicon #sleep #sleep-pressure #solar #sound #space #spectra #staging #states-of-matter #statistics #structures #sunlight #synapse #tendons #tension #thermal-resistance #thermal-storage #thermodynamics #thrust #titration #tokens #torque #traction #traffic #training #transformers #transistors #transmission #truss #truth-tables #turntables #uncertainty #urine #vaccines #valve-timing #valves #vision #voltage #water #watershed #waves #weather #white-blood-cells #wind-tunnel #wings #work
Interactive exploration Brain & Senses Sleep and the body clock Why do time awake and time of day both matter for sleep? Change a fictional sleep history, catch the moment two curves meet, and separate a local clock change from a biological clock. Then follow light information from eye to brain.
Interactive model & evidence Explore at your own pace
Interactive exploration Brain & Senses Neurons and nerve signals How does a nerve cell send a message? Nudge a membrane, discover when a spike appears, test its recovery, and cross a chemical synapse. Then inspect a real potassium-channel structure.
3D model & experiments Explore at your own pace
Interactive exploration Brain & Senses Eyes and vision How does your eye bring the world into focus? Open a sourced 3D eye, move a target nearer, and catch the moment its light comes together. Then discover why a smaller pupil is different from better focus.
3D model & experiments Explore at your own pace
Interactive exploration Brain & Senses Hearing and the ear How does a sound reach your brain? Start with a vibration. Follow air, eardrum, tiny bones and hair cells, then see why the message reaching your brain is a different kind of signal.
Interactive model & diagrams Explore at your own pace
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Where will curiosity take us? 
Interactive exploration
Interactive exploration
Interactive exploration
Interactive exploration