[Verse 1] Start up top where the dorsal sits, grid cells stacked in tight little bits, small hexagons, close-set and neat, firing fast like a metronome beat. Feeds the dorsal hippocampus, precise little zone, place fields shrink down to a pinpoint of bone, this is your GPS with the zoom all the way in, centimeters matter here, that's the discipline. [Chorus] Dorsal's fine, ventral's wide, small grid north, big grid south side, top gives detail, bottom gives feel, one axis, two different deals. Dorsal maps the crack in the floor, ventral maps the mood at the door, posterior's precise, anterior's the gist, remember the bands, don't let 'em get missed. [Verse 2] Now glide on down where the ventral resides, grid spacing stretches out, exaggerated strides, coarse hexagons, loose in their spread, tuned less to inches, more to what's ahead. Ventral hippocampus catches this thread, laced up with amygdala, stress, and dread, context blurs into a general shape, not "where's the corner," more "is this an escape?" Emotion rides shotgun on this coarser plane, generalizing danger, not tracing the lane. [Chorus] Dorsal's fine, ventral's wide, small grid north, big grid south side, top gives detail, bottom gives feel, one axis, two different deals. Dorsal maps the crack in the floor, ventral maps the mood at the door, posterior's precise, anterior's the gist, remember the bands, don't let 'em get missed. [Verse 3] Between the poles it's never a switch, it's modules — Brun found the graded stitch, Stensola stacked discrete steps in the scale, each module a rung on a gradient trail, mixing coarse and fine as you travel the band, no hard border, more a shifting sandband. Blueprint for how the whole system's designed, scale by scale, a topographic mind. [Bridge] Now flip to the human, the axis stays true, posterior hippocampus does what dorsal would do, fine-grained detail, the where and the when, anterior handles the gist and the sin — emotion, valence, the fuzzy terrain, same climb, different name, same functional gain. So picture the lesion, run the prediction through: knock out the ventral, what does the rat do? Loses the dread, can't generalize fear, context blending goes fuzzy, the danger's not clear. Knock out the dorsal, precision departs, place fields go sloppy, fine mapping falls apart — still knows the room's scary, still feels the alarm, just can't pinpoint the corner where it does harm. [Chorus] Dorsal's fine, ventral's wide, small grid north, big grid south side, top gives detail, bottom gives feel, one axis, two different deals. Dorsal maps the crack in the floor, ventral maps the mood at the door, posterior's precise, anterior's the gist, remember the bands, don't let 'em get missed. [Outro] One long axis, split in degree, dorsal's the ruler, ventral's the sea, strange et al drew the whole map out clear — know your bands, and you'll know where you are, and where the fear.
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