[Verse 1]
Down in the entorhinal, second floor, take a look,
Layer II's the gateway, write it straight in your book,
Two tribes live here, never mixing their blood,
Reelin runs the stellate crew, calbindin owns the stud,
Islands in a sea of cortex, patches on the map,
Every patch a passport, every passport got a stamp,
One crew ships to hippocampus, one stays local and tight,
Learn the split today, you'll never lose the sight.
[Chorus]
Reelin, stellate, fan-shaped, perforant path,
Straight to dentate, straight to CA3, do the math,
Calbindin, pyramidal, island in the patch,
Bound for CA1, crossing over, matching latch,
Layer Two, the launchpad, the busiest of floors,
Grid cells clocking distance while the pyramids keep score.
[Verse 2]
Stellate cells don't shake hands, no direct wire,
Couey oh-thirteen showed the circuit require
Inhibitory go-betweens, interneurons in the middle,
Excitation's outlawed — that's the inhibition riddle,
Feeds the CAN model, the "inhibition-only" kind,
Grid cell rhythm built on braking, not the driving mind,
Fan cells spread out wide, dendrites like a kite,
Perforant path punches through, dentate gyrus bites.
[Verse 3]
Now the pyramidal squad, calbindin on their chest,
Clustered up in islands, never blend, never mesh,
Kitamura fourteen traced the wire, showed the plan,
CA1 gets the message, contralateral EC too,
Mirror-image whisper, cortex talking to its twin,
While stellate handles distance, pyramidal locks the timing in,
More theta-locked, conjunctive, heading, speed, and place,
Two currencies of coding sharing the same space.
[Chorus]
Reelin, stellate, fan-shaped, perforant path,
Straight to dentate, straight to CA3, do the math,
Calbindin, pyramidal, island in the patch,
Bound for CA1, crossing over, matching latch,
Layer Two, the launchpad, the busiest of floors,
Grid cells clocking distance while the pyramids keep score.
[Verse 4]
HCN current gives the sag, a slump then a rise,
Subthreshold oscillation, Ray fourteen realized
It shifts along the axis, dorsal tight and fast,
Ventral loose and lazy, spacing scales are cast,
This is the tuning knob for how wide the grid can grow,
Dorsoventral gradient, the rhythm's undertow,
But layer two's a target, fragile from the start,
Alzheimer's finds it earliest, stellate cells depart.
[Bridge]
First to flicker, first to fall, tau tangles take the floor,
Lose the fan, lose the map — you can't find the door,
Remember which cell dies first when the pathology creeps,
The entorhinal whisper is the first stone the plaque keeps.
[Chorus]
Reelin, stellate, fan-shaped, perforant path,
Straight to dentate, straight to CA3, do the math,
Calbindin, pyramidal, island in the patch,
Bound for CA1, crossing over, matching latch,
Layer Two, the launchpad, the busiest of floors,
Grid cells clocking distance while the pyramids keep score.