[Eeglablist] How much data is necessary for ICA?

[Son, D.M.E. van]

Dear EEGLab list members,

I have a question related to ocular and artifact rejection with ICA to obtain ERPs. I read ICA might not be ideal if there are not enough data points (e.g. if you only have a short EEG recording per subject). There seem to be ways to cope with this, such as reducing the number of channels, having a higher sample rate or using PCA.

We will have 20 minutes of data per subject, 128 channels and recorded the data with 1024 p/s. Does anyone know whether this will be enough to confidently apply the ICA? Is reducing the number of channels or an extra PCA before ICA recommended?

Many thanks in advance

Dana