[Verse 1] Six floors in the cortex, no elevator, count 'em stair by stair, Layer one's the attic, mostly fiber, hardly any cell bodies there, Drop to layer two, the traffic hub, stellate cells shaped like a fan, Reelin tags them green under the scope, that's the maker's stamp on the plan, Next door pyramidal neighbors flash calbindin, different badge, same floor, Grouped in clusters like a mosaic tile, that's the islands, that's the lore. [Chorus] Two for stellate, reelin bright, islands floating in patchy light, Three for pyramid, standing proud, dissecans splits the crowd, Five and six, the exit door, output rolling to the hippocampal shore, Learn the layers, learn the code, superficial in, deep out the road. [Verse 2] Kitamura's study dropped the map, islands ain't just pretty design, Stellate clusters wire to CA1, timing memory, keeping the line, Ray's research found patches too, calbindin pyramids bunched in a nest, Different circuit, different job, superficial layer's a crowded test, Fan cells spread their dendrites wide like satellite dishes catching grid, Grid cell firing, hexagon math, that's the code that layer two hid. [Verse 3] Drop below to layer three, pyramidal cells lined in a row, Feed the CA1 straight up top, monosynaptic, steady flow, Then the gap, lamina dissecans, cell-sparse gorge cutting the slope, Landmark border, anatomists chart it with compass and rope, Five and six, thick and deep, output layer, the loop comes home, Subiculum whispers back through here, hippocampal news finds its own dome. [Verse 4] Early studies wired stellate cells straight to the scope, Subthreshold oscillation humming, rhythmic pulse, theta's rope, HCN channels crack the door, current sneaks in when membrane's low, Resonance peaks near theta band, that's the tempo the grid cells know, Sag and rebound, the signature curve, mixed conductance tunes the beat, That biophysics builds the map you use to navigate the street. [Bridge] Superficial layers swallow the world, cortex whispering what it heard, Deep layers speak the hippocampus back, translating every word, In through two and three, the climb, out through five and six, the rhyme, Loop closes like a snake eating tail, structure keeping perfect time. [Chorus] Two for stellate, reelin bright, islands floating in patchy light, Three for pyramid, standing proud, dissecans splits the crowd, Five and six, the exit door, output rolling to the hippocampal shore, Learn the layers, learn the code, superficial in, deep out the road. [Outro] Six layers, one circuit, draw it out by hand, Mark the markers, trace the axons, understand the land, Stellate, pyramid, dissecans, deep — the entorhinal keep.
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