[Verse 1] Two rivers run down from the brainstem's old tower, One hugs the outer wall, one claims the core's power. The lateral line through the corticospinal cable Threads every finger, keeps your grip able. Rubrospinal rides along for the climb, Steadies your reach when you're buying time, Distal and clever, the fingertip crew, Carving fine motion the way sculptors do. [Chorus] Lateral for the fingers, medial for the frame, One writes your name, one holds the same. Cortico, rubro — precision's own crew, Reticulo, vestibulo, tecto pull you through. Side for the skill, middle for the stand, That's how the brainstem conducts the whole band. [Verse 2] Deep in your ear there's a tiny curled sea, Fluid tips over and tells your spine where to be. Vestibulospinal reads the tilt, the fall, the lean, Snaps your neck level before you hit the scene. It's the plumb line tethered to gravity's thread, Squaring your shoulders, propping up your head, A gyroscope whispering under your skin, Keeping the tower from toppling in. [Verse 3] Before you even lift a single arm, Reticulospinal's already ringing the alarm, It braces your belly, shifts your weight behind, A silent stagehand moving ahead of your mind. Anticipation dressed as posture's quiet art, The body knows the cue before the downbeat starts, Lean a little backward, plant it through your feet, So the reach don't topple when the arm meets the street. [Chorus] Lateral for the fingers, medial for the frame, One writes your name, one holds the same. Cortico, rubro — precision's own crew, Reticulo, vestibulo, tecto pull you through. Side for the skill, middle for the stand, That's how the brainstem conducts the whole band. [Bridge] Say the cortical road gets washed out by a stroke, Corticospinal silent, the fine thread snapped and broke. But reticulospinal climbs up from the back stair, Cruder, rougher, but it's willing and it's there. Proximal muscles answer, the shoulder finds its brace, The old pathway steps in to hold the fallen place, Not the same sharp signature, but movement all the same, The brainstem's understudy learning the main role's name. [Verse 4] Tectospinal turns your head toward the clap, the gleam, Orients your gaze to the edge of a sudden dream, Superior colliculus throws the cable down, Snaps your neck to the sound without a frown, Orienting, bracing, standing, reaching true, Four quiet captains steering what the cortex can't do. [Outro] Side for the skill, middle for the stand, Lateral, medial — hold the whole plan, Inner ear whispers, the stagehand primes the frame, Even after the storm cloud, the old road learns the name.
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