[Eeglablist] Visually add markers to data?

[Bradley Voytek]

Johan:

I'd highly recommend using an algorithmic method for extracting EMG
onsets, as it's much faster, and less likely to be biased (depending
on the method you use).

For example, after subtracting your two EMG channels, highpass filter
the surrogate channel to isolate the EMG activity.

If your SNR is good, then you could proceed in several easy ways. One
way would be to get the analytic amplitude and find points that cross
a threshold. Another would be to create a logical vector of points
that cross a threshold, and then take the diff(vector) to isolate
onsets and offsets.

If your SNR isn't good, then you need an iterative process of
thresholding, isolating, etc.

::brad voytek

On Sun, Sep 28, 2008 at 7:02 AM, Johan <johanvandermeer at gmail.com> wrote:
> Hello,
>
> I'd like to visually add event-markers as i'm scrolling the data in
> eegplot().
>
> However... the only way i currently see to do this, is by command-line... so
> is there any way to do this in the gui also?
>
> (i'm searching EMG traces, and i'd like to place an event (EEG.type='b') any
> time I see a sudden burst of EMG activity; much like in Brainvision
> Analyzer).
>
> Regards,
>
> Johan van der Meer
> PhD Student
> Academic Medical Centre
> Amsterdam
>
>
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