Shank Separation
Shank separation is the centre-to-centre distance between neighbouring shanks on a multi-shank silicon probe, in micrometres; it decides whether the shanks sample one structure at several points or separate structures at once.
It is the fourth field of a multi-shank probe name — the 200 in A4x8-tet-5mm-100-200-177 — and it is the across-shank counterpart of site pitch.
The reasoning is the detection-radius argument turned sideways. A shank sees a cylinder of tissue about 200 µm across, so shanks separated by 200 µm sample adjacent, non-overlapping columns — the setting on most catalog multi-shank designs, and the one that reads across a cortical map. Closer separation, 125 or 150 µm, lets neighbouring shanks see some of the same neurons and is used where unit isolation across shanks matters; wider separation, 400 to 500 µm, places shanks in different structures or different cortical areas in one insertion, and the Matrix platform reaches 1.5 mm and more to sample a volume. Separation and shank count together set the width of the site span.
Typical values
| Catalog multi-shank designs | 125 to 500 µm; 200 µm on about half |
|---|---|
| Matrix 3D platform | up to 1.8 mm |
| Design-space parameter | Shank separation (shankSepUm) |