[Verse 1] Entorhinal cortex sends its signal through the gate But similar patterns cause a computational fate Interference strikes when memories collide So dentate gyrus steps up to be our guide Two hundred thousand inputs from layer two Meet a million granule cells with work to do Expansion coding spreads the narrow stream Into dimensions where separation's the dream [Chorus] Pattern separation, decorrelation station Sparse and wide, keeping memories alive One percent firing, winner-take-most wiring Mossy fibers carry what survives DG breaks apart what looks the same So CA3 can play the storage game [Verse 2] Perforant path delivers overlapping scenes But granule cells stay quiet, lean and mean Feedforward inhibition clamps them down tight While basket cells patrol the soma site HIPP cells lurk at dendrites in the zone Making sure few neurons claim the throne Extreme sparsity keeps the code clean Lowest overlap you've ever seen [Chorus] Pattern separation, decorrelation station Sparse and wide, keeping memories alive One percent firing, winner-take-most wiring Mossy fibers carry what survives DG breaks apart what looks the same So CA3 can play the storage game [Bridge] Mossy cells in hilus dance between Exciting granule cells while recruiting the machine Contralateral connections span the gap Inner molecular layer completes the map Adult neurogenesis adds fresh troops To the pattern-busting feedback loops [Verse 3] High dimensions make it easier to split What lower spaces couldn't separate a bit Like cerebellar granules and ML layers too Expansion is the computational coup Feedback inhibition creates the race Where few can win but all compete for space The sparse survivors carry signals clean Through the hippocampal machine [Verse 4] Activity-dependent competition reigns As similar inputs fight through neural chains LTP strengthens winners in the sparse code While weaker synapses fade along the road Decorrelated outputs flow downstream Supporting memory's recall scheme Each granule cell becomes a unique key Unlocking stored identity [Chorus] Pattern separation, decorrelation station Sparse and wide, keeping memories alive One percent firing, winner-take-most wiring Mossy fibers carry what survives DG breaks apart what looks the same So CA3 can play the storage game [Outro] From EC's crowded input to CA3's domain DG transforms the overlapping strain Into distinct patterns, crystal clear No interference, no memory fear
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