I am analyzing a MEG detaset for which I need to compute the data covariance for the LCMV beamformer computation. The problem is that the inter-trial interval for my experiment is too short, causing the baseline period for one trial to be contaminated by the previous post-movement rebound trial. I am wondering what is the impact of this contamination on the baseline for the data covariance, and ultimately on the LCMV beamformer. I am currently using as baseline -2.5s to 0s, but I could also use -0.5s to 0s in order to reduce the contamination from the previous trial. Please let me know if you have any suggestions to get around this issue.