[Verse 1] Two highways in your skull they say, ventral what and dorsal where But hold your horses, slow your roll, the truth needs careful care These streams ain't rivers running solo, they're chatting all day long Cross-connected at each junction, information flowing strong [Chorus] Keep your caveats close, don't let assumptions lead you wrong The two-stream map's a starting point, not the final song Cross-connected, coarse and messy, monkey brains ain't quite the same Use it as your routing compass, not your neuron-naming game [Verse 2] That dichotomy sounds so clean and neat, but dig a little deeper down Each stream's got specialized neighborhoods, not just one side of town Some jobs like three-dimensional shapes recruit from both the crews So don't go boxing every function into tidy what-and-where news [Chorus] Keep your caveats close, don't let assumptions lead you wrong The two-stream map's a starting point, not the final song Cross-connected, coarse and messy, monkey brains ain't quite the same Use it as your routing compass, not your neuron-naming game [Verse 3] Now monkey studies paved the way, but humans took a different turn Parietal cortex stretched and shifted, new lessons we had to learn Homology ain't perfect matching, evolution played some tricks So primate papers tell part of the tale, but human brains got different licks [Verse 4] When lesions hit the parietal zone, the symptoms tell a complex tale Not just pure spatial navigation that comes grinding to a fail Visual attention gets all scrambled, reaching movements go askew But object recognition lingers, so the what-stream's pushing through [Bridge] Where and how ain't fighting rivals, they're dancing partners on the floor Dorsal stream does spatial mapping and action planning, maybe more Sub-areas split the workload up, each corner plays its part Don't pin it all on single cells, that's missing the art [Chorus] Keep your caveats close, don't let assumptions lead you wrong The two-stream map's a starting point, not the final song Cross-connected, coarse and messy, monkey brains ain't quite the same Use it as your routing compass, not your neuron-naming game [Outro] High-level routing, that's the game Single neurons? Not the same Keep those caveats burning bright In your visual processing sight
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