[Verse 1]
In the cortex where the columns stand
Each layer speaks in different hands
Predictions flowing from the top
While errors bubble up and swap
Every unit holds a value tight
With error signals burning bright
The brain's own matrix, row by row
Teaching us what we need to know
[Chorus]
Top-down predictions, bottom-up mistakes
Hierarchical coding, that's what it takes
Value plus error, dancing in time
Local updates keeping rhythm and rhyme
Rao and Ballard showed us the way
Predictive coding night and day
[Verse 2]
From layer six down to layer one
The guessing game has just begun
What should I see, what should I hear
The prediction whispers crystal clear
But when reality doesn't match
Error units start to catch
The difference screaming up the chain
Adjusting weights to ease the pain
[Chorus]
Top-down predictions, bottom-up mistakes
Hierarchical coding, that's what it takes
Value plus error, dancing in time
Local updates keeping rhythm and rhyme
Rao and Ballard showed us the way
Predictive coding night and day
[Bridge]
Pre-synaptic meets post-synaptic fire
Local rules that never tire
No global teacher needed here
Just neighbors talking crystal clear
Whittington-Bogacz proved it true
Under conditions crystal blue
Predictive coding finds the grade
Exact as backprop ever made
[Verse 3]
Each computational unit sings
Two voices on cellular wings
One voice predicts what ought to be
One voice corrects what eyes can see
The mathematics flows like wine
Through dendrites in a perfect line
Distributed but unified
Nature's algorithm amplified
[Verse 4]
From visual cortex to the frontal lobe
Information wrapped in neural robe
Each level builds upon the last
Present, future meeting past
Object features, shapes and lines
Abstract concepts, grand designs
The hierarchy climbs so high
Until we touch the reasoning sky
[Chorus]
Top-down predictions, bottom-up mistakes
Hierarchical coding, that's what it takes
Value plus error, dancing in time
Local updates keeping rhythm and rhyme
Rao and Ballard showed us the way
Predictive coding night and day
[Outro]
In every column, every cell
The future and the past rebel
But in their struggle, truth emerges
As prediction slowly converges