[Verse 1] Six floors stacked in the entorhinal tower, Two and three throw the signal, that's the opening hour, Down through the fascia, hippocampus takes the call, CA1 hands it to Vb, deepest floor of all, Vb ain't just an exit, it's a stairwell in disguise, Climbing back to II and III, closing up the ties, Deep to superficial, that's the loop's whole name, Same address, different floor, but it's playing the same game. [Chorus] Two-three down, five comes round, Deep to superficial, that's the sound, Loop don't leak, loop don't break, EC's echo keeps the pattern awake, Two-three down, five comes round, Recurrent wiring, hippocampus bound. [Verse 2] Picture a proofreader checking yesterday's page, Predicted input meets the real one, backstage, That's the comparison the circuit's built to run, Mismatch detected, correction just begun, Attractor states get steadied like a spinning plate, Vb's feedback keeps the pattern from going out of date, And at the doorway, II and III, a bouncer stands with pride, Gating what's admitted to the hippocampal ride. [Chorus] Two-three down, five comes round, Deep to superficial, that's the sound, Loop don't leak, loop don't break, EC's echo keeps the pattern awake, Two-three down, five comes round, Recurrent wiring, hippocampus bound. [Verse 3] Sürmeli, twenty-fifteen, traced the axon home, Showed the deep layers don't just wander on their own, Ohara, twenty-eighteen, mapped the Vb spine, Confirmed the climb from basement floor to attic line, Not a one-way alley, not a dead-end hall, It's a whispering gallery, bouncing signals wall to wall, The hippocampus murmurs, cortex answers back, A conversation looping on a recurrent track. [Bridge] So what's it really computing, this circuit tucked so deep, A referee for memory or a rhythm none can keep, Write your hypothesis, don't just repeat the claim, Is it error-checking, or stabilizing the frame, Maybe it's both at once, a gatekeeper with a scope, Deep to superficial — call it entorhinal rope. [Verse 4] Grid cells whisper coordinates, place cells sing them true, Vb keeps the compass steady, so the map stays new, Every loop's a heartbeat in the cortex-hippocampal chain, Deep to superficial, memory's refrain, Six floors talking circles, never losing pace, The entorhinal tower holds the architecture of space, Signals climb and settle, then descend again, A building that remembers every place it's been. [Chorus] Two-three down, five comes round, Say it till the pattern's locked and sound, Loop don't leak, loop don't break, EC's echo keeps the pattern awake, Two-three down, five comes round, Recurrent wiring, hippocampus bound. [Outro] Layer Vb climbing, closing up the ring, Deep to superficial — hear the loop still sing, Predict it, gate it, hold the trace in place, The tower talks to itself and calls it space.
← C2 — The Return Loop (Hippocampus → Deep EC → Cortex) | C4 — The Layer II Inhibitory Microcircuit →