[Verse 1] Down in the visual cortex maze Where neurons dance in layered ways Felleman mapped the wiring game In macaque brains, the rules the same Feedforward flows from layers two and three Straight down to four, like water to the sea But feedback takes a different route From five and six, a different suit [Chorus] It's not a ladder climbing high It's not a one-way ticket ride The feedback outnumbers the feed A loop that settles, that's what we need Two-three to four goes up the chain Five-six comes back like driving rain More synapses flowing down than up Vision's not a bottom cup [Verse 2] The laminar signature tells the tale Deep layers send their backwards mail Avoiding four like toxic ground In layers one and six they're found Hierarchical levels get assigned By this pattern anatomists find But here's the twist that shakes the tree Backwards traffic runs more free [Chorus] It's not a ladder climbing high It's not a one-way ticket ride The feedback outnumbers the feed A loop that settles, that's what we need Two-three to four goes up the chain Five-six comes back like driving rain More synapses flowing down than up Vision's not a bottom cup [Bridge] V1 gets more from cortical friends Than from LGN where the signal begins Higher areas project massively back Like supervisors checking the stack Local recurrence joins the choir Feedback sets the brain on fire [Verse 3] Forget the sweep through layered decks This ain't no simple reflex The brain's a settlement machine Where top-down meets the visual scene Asymmetric wiring rules the day More connections flow the backwards way The quantitative truth cuts deep Vision's not a one-way sweep [Verse 4] From MT back to V1's door The feedback highways carry more Than forward streams could ever hold A story that needs to be told Predictive coding sets the stage Where expectation writes the page The brain predicts what it should see Then checks against reality [Chorus] It's not a ladder climbing high It's not a one-way ticket ride The feedback outnumbers the feed A loop that settles, that's what we need Two-three to four goes up the chain Five-six comes back like driving rain More synapses flowing down than up Vision's not a bottom cup [Outro] When you see the world around Remember how the wires are wound Backwards flow exceeds the climb In the brain's asymmetric rhyme [Final Chorus] It's not a ladder climbing high It's not a one-way ticket ride The feedback outnumbers the feed A loop that settles, that's what we need
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