[Verse 1] Nineteen eighty-two, two scientists tracing light, Ungerleider and Mishkin split the visual flight, One road runs ventral, naming shapes down below, One road runs dorsal, charting where things go, They called it the "where" path, a compass in the brain, Mapping space and motion through the occipital lane. [Verse 2] Ten years on, Goodale and Milner turned the key, Not just "where" but "how" — vision built for the body, Patient DF, her temple lobe undone, Couldn't name the tilt of a slot, not a single one, Yet she posted cards clean through the crooked door, Her hand knew the angle her mind could not explain for. [Chorus] Dorsal stream, dorsal stream, reaching through the haze, "Where" became "how" in the parietal maze, Dorso-dorsal grips it, ventro-dorsal knows the plan, Two rivers, one purpose: turning sight into a hand. [Verse 3] Rizzolatti and Matelli carved the river into two, Dorso-dorsal climbs through V6 and V6A too, MIP hands off to premotor dorsal, quick and clean, Online reaching, fixing what the fingers haven't seen, Ventro-dorsal wanders lower, MT and MST, Through the inferior parietal lobe to premotor ventral's nest, Binkofski and Buxbaum stretched the map to human praxis — That's the skillful art of doing, tool and gesture's axis. [Verse 4] Kravitz, Saleem, Baker, Mishkin, twenty-eleven's call, Three roads leaving parietal cortex, branching for us all, One climbs to the prefrontal, holding space in working mind, One drops to the premotor, guiding hands that reach and find, One slips through the precuneus, retrosplenial door behind, Peregrinating onward — that's to wander and to roam — Tracing hallways of a building till the body's found its home. [Chorus] Dorsal stream, dorsal stream, reaching through the haze, "Where" became "how" in the parietal maze, Dorso-dorsal grips it, ventro-dorsal knows the plan, Two rivers, one purpose: turning sight into a hand. [Bridge] V3A and human V6, Pitzalis drew it clear, MT, MST, and V7, feeding forward here, IPS zero whispers motion, borders bend and bow, AIP and LIP borrow from the ventral stream somehow, Borra's wiring from the temporal lobe creeps up to stay, Shape and form seep inward, lending object cues to play. [Verse 5] Bálint's syndrome shows the wreckage when the dorsal roads collide, Simultanagnosia narrows all the world to one small side, Optic ataxia fumbles, reaching never finds its mark, Damage bilateral, parietal, leaves the hand to grope the dark, Yet perception stays intact — she still can name the cup, The split runs clean and deep, it's how the pieces add right up. [Outro] Where to how, dorsal split in two, Three outputs branching, each road built for you, Prefrontal, premotor, precuneus to roam — The parietal lobe turns raw sight into a home. [Chorus] Dorsal stream, dorsal stream, reaching through the haze, "Where" became "how" in the parietal maze, Dorso-dorsal grips it, ventro-dorsal knows the plan, Two rivers, one purpose: turning sight into a hand.
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