where is the "tip" of a probe?

[bendichter]

We want to combine the probe interface specification of a probe with the surgical coordinates for translation, rotation and depth (e.g. from Pinpoint) to get the anticipated electrode positions on an atlas brain. The surgical coordinates are with respect to the "tip" of the probe. To combine these, we would need an indication of where the "tip" is on each probe.

You might think to make the tip (0,0), however in the probeinterface library, it looks like of the the electrodes is (0,0). Is there any to indicate where the tip is in probe interface? Could the tip be the location of the first contour point? Otherwise, could we indicate the coordinates of the tip in a separate field?

[samuelgarcia]

Hi Ben.
very often the 0,0 is the depper contact.
We should have an optional attribute for the tip position I think.
We could infer it by the minimmum on the contour but for multi shank we have several tips.

[alejoe91]

I think that we can safely assume that the tip is the deepest contour point. In case of multiple-shanks, we could write a simple function that estimates the tip for each shank based on the x-coordinates.