Cerebral Explorer: Memory Quest

A nod to Invincible Island (Richard Shepherd Software, 1983), Pete Cooke’s text adventure for the ZX Spectrum, where you explore an island, examine everything, gather seven parchments and try not to fall into a pit. Here the island is a brain, and there’s no typing: you move with a compass and choose what to examine, take and use. It’s 8:05 on a school morning, Alex can’t find the house keys, and you have to rebuild the memory of where they went.

The science

• The map. You travel from the spinal cord up the brainstem (medulla, pons, midbrain) to the thalamus, the brain’s relay station, and out to both hemispheres: language in Broca’s and Wernicke’s areas, the motor cortex and the sensory cortex with its homunculus, the prefrontal cortex, the cerebellum, the hypothalamus, the pituitary gland, the amygdala and the hippocampus, where memories are made.
• The five senses. Sight, from the retina through the optic chiasm to the visual cortex; hearing, in the auditory cortex; smell, in the olfactory bulb, the only sense that skips the thalamus; taste, in the insula; and touch, in the sensory cortex.
• Receptors. Many of the senses and messengers in the game work through G protein-coupled receptors: rhodopsin for light, about 400 smell receptors, the sweet, bitter and umami taste receptors, and the adrenergic receptors for noradrenaline from the locus coeruleus. Brian Kobilka and Robert Lefkowitz shared the 2012 Nobel Prize in Chemistry for their work on GPCRs; one of the structures on this site is a β2-adrenergic receptor from that work.
• Structures and Nobel Prizes along the way. Ramón y Cajal’s drawings of neurons (your seven sketches), the potassium channel (Roderick MacKinnon), aquaporins (Peter Agre), TRPV1 by cryo-electron microscopy (David Julius), the SNARE proteins of vesicle release, AMPA receptors and Eric Kandel’s work on memory, and ATP synthase (John Walker; see also the F1-ATPase I helped with), alongside Hodgkin and Huxley, Hubel and Wiesel, Sperry, the place and grid cells of O’Keefe and the Mosers, and how cells sense oxygen.
• Things to fix. A stroke, whose penumbra can still be saved if the clot is dissolved in time (think F.A.S.T.); an epileptic focus, calmed by GABA; and a viral infection, cleared by microglia. You don’t have to fix them to win, but you score more if you do.

Where the game cuts corners

• Brain regions aren’t rooms joined by corridors, and nothing in the brain is tidy enough to map with north, south, east and west. The map is a schematic.
• A memory isn’t three neat pieces sitting in three places waiting to be collected. It’s a pattern of connections spread across many brain areas, strengthened at synapses, and rebuilt a little each time it’s recalled.
• Oxytocin, GABA and tPA can’t be carried about in a bag. In life, they are released where and when they’re needed (or, for tPA, given by doctors as a medicine).
• And no amount of explorers will find your keys for you. A good habit (one hook by the door) works better.