[Mne_analysis] preprocessing/ICA: movement artifacts vs blinks

[Dan McCloy]

I have EEG data where the recording was continuous during breaks between
blocks, so there are lots of movement artifacts during temporal spans that
I ultimately don't care about.  If I just epoch the data, those temporal
spans go away, but I want to do blink rejection.  Doing blink rejection on
an Epochs object doesn't seem to work out of the box, and doing it on each
epoch individually seems inefficient and possibly dodgy.

Question 1: is there a sensible way to run blink rejection on an Epochs
object that I haven't thought of?

Assuming I need to reject blinks using the Raw object, here are more
details:  I don't have a separate EOG channel, so I'm using a forehead
electrode (Fp1) that seems to reflect the blinks quite well (based on
visual inspection of raw.plot()).  But the movement artifacts are much
bigger than the blinks, so ICA is not working very well at catching the
actual blinks; in a ~70 minute recording it is detecting as few as 12
"blinks" for some subjects, and those events are localized around what are
clearly movement artifacts or other large between-block drifts.

Question 2: Other than manually zeroing out values in raw._data, is there a
way to mask or delete time spans of the Raw object that you want ICA to
ignore?  I know about raw.crop() but that only works for beginning/end
times.

Question 3: is there some other approach I'm not thinking of that might get
around this problem?
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