Module 5 — The assembled circuit: trisynaptic loop, direct paths, and rhythms

samba afropiano, korean drumstep, illbient cumbia, hyper-southern rock · 3:56

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Lyrics

[Verse 1]
From neocortex down to entorhinal gate
Layer two begins the trisynaptic fate
Perforant path to dentate gyrus flows
First synapse where the pattern encoding goes
Mossy fibers carry sparse and clean
DG to CA3, the sharpest scene
Schaffer collaterals complete the chain
CA3 to CA1, the memory train

[Chorus]
Three synapses dancing through the hippocampal core
Direct paths bypass what came before
Theta waves at four to twelve hertz strong
Gamma nests inside to sing along
Hold the circuit diagram tight in mind
Trisynaptic loop with shortcuts intertwined

[Verse 2]
But wait there's more than classic pathways show
Direct routes let the information flow
Layer two can jump straight to CA3
Perforant path alternative you see
Layer three takes temporoammonic flight
Straight to CA1 without the fight
Parallel processing, dual highway lanes
Backup routes for memory's refrains

[Chorus]
Three synapses dancing through the hippocampal core
Direct paths bypass what came before
Theta waves at four to twelve hertz strong
Gamma nests inside to sing along
Hold the circuit diagram tight in mind
Trisynaptic loop with shortcuts intertwined

[Bridge]
CA3 talks back to CA3 recursive
Recurrent networks, memory immersive
Commissural bridges span the hemisphere divide
DG, CA3, CA1 on either side
CA1 to subiculum the journey goes
Deep layer EC where it all flows home

[Verse 3]
Theta rhythm rules the exploration game
REM sleep and movement stake their claim
Phase precession marks the temporal code
Different phases choose encode or decode
Gamma frequencies in nested embrace
Thirty to one hundred, cell assembly space
Slow gamma rides CA3's input stream
Fast gamma surfs EC's routing scheme

[Verse 4]
When offline mode takes control at night
Replay consolidates what felt just right
Sharp wave ripples in the quiet hours
Transfer memories using hippocampus powers
From temporary store to cortical home
The trisynaptic loop has found its zone
Subiculum bridges to the final stage
Neocortex completes the memory page

[Verse 5]
Place cells fire when location's found
Grid cells map the spatial ground
Time cells count the moments passing by
Border cells mark boundaries that lie
Pattern separation makes each memory unique
While pattern completion helps recall technique
Neurogenesis adds fresh granule cells
Adult-born neurons with stories to tell

[Chorus]
Three synapses dancing through the hippocampal core
Direct paths bypass what came before
Theta waves at four to twelve hertz strong
Gamma nests inside to sing along
Hold the circuit diagram tight in mind
Trisynaptic loop with shortcuts intertwined

[Outro]
EC layers two and three divide the flow
DG, CA3, CA1 in sequence go
Oscillations mark the rhythm's beat
Memory circuit now complete

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