[Verse 1] When photons hit your retina's stage The eye don't send what cameras gauge No pixels marching line by line Instead it runs a different design Twenty channels spike and fire Each one a specialized wire Ganglion cells sort the scene Into streams you've never seen [Chorus] Twenty channels, twenty views ON and OFF in different hues Center-surround begins the tale Motion, color, never fail Tiling patterns, complete and wide Twenty filters side by side From the eye the story flows In parallel streams it goes [Verse 2] Kuffler back in fifty-three Found the code we couldn't see Center bright and surround dark Or flip the switch, reverse the mark Each ganglion type spreads its net Across the retina's silhouette Complete coverage, overlapping maps Twenty different neural taps [Chorus] Twenty channels, twenty views ON and OFF in different hues Center-surround begins the tale Motion, color, never fail Tiling patterns, complete and wide Twenty filters side by side From the eye the story flows In parallel streams it goes [Verse 3] Color opponents take their stance Red-green, blue-yellow advance Transient motion catches change Direction selectors arrange Looming signals sound alarm Differential motion means harm Specialized channels stand on guard While others make the basics hard [Verse 4] Midget cells for fine detail Parasol cells that never fail Y-cells respond to moving edge X-cells keep their solemn pledge To linear summation's rule While Y-cells break it like a fool Sustained response or transient burst Each channel knows which comes first [Bridge] In the fovea packed so tight Sampling dense for sharpest sight Out toward the edge it thins That's where magnification begins Not the cortex making space Retina sets the sampling pace Best-understood circuit in the brain Each connection mapped in molecular chain [Chorus] Twenty channels, twenty views ON and OFF in different hues Center-surround begins the tale Motion, color, never fail Tiling patterns, complete and wide Twenty filters side by side From the eye the story flows In parallel streams it goes [Outro] Efficient coding theory shows Why evolution chose These twenty streams of spiking code Down the optic nerve they rode No pixels on this neural wire Just filtered scenes that never tire [Final Chorus] Twenty channels, twenty views ON and OFF in different hues Center-surround begins the tale Motion, color, never fail From the eye the story flows In parallel streams it goes
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