What type of error is here with forward solution?

I computed the forward model with vecterview example in bst after I extract just the meg squid,
exery thing work fine,

I then worked with default anatomy and the extracted meg (every think looks right in the coregisteration)
image

I plotted the values for a (semi-)random channel (e.g., "80"):

plt.plot(gain[80,:])
plt.show
image
and looks like there are outliers in the forward solution, approximately around vertex #36390-36392..

What happen?

If you have computed the BEM OpenMEEG solution, it is sometimes unstable at some limit conditions (when the dipoles are too close to the inner layers).

Right-click on the forward model > View leadfield vectors.
Post the screen capture here. You should see your outliers here.

Post also a screen capture showing: the cortex surface without smoothing + the inner skull in red + the other layers you've been using.
Set the inner skull transparency to 0% and check if there is any point of the cortex that seems outside the inner skull.

Right-click on the cortex you've be estimating the leadfield for > Force inside skull.
Compute again the leadfield. Does it change anything?

image
it seems that there is no point of the cortex that seems outside the inner skull.

image

image

Indeed, we can see one abnormal field in the right-temporal area.
Use the overlapping spheres method for MEG, instead of the OpenMEEG BEM which has this instabilities, this is our general recommendation.