Results of simulations. Top: the trial-invariant spatial response pattern R at j = 25, i.e. for the time point at the middle of the analyzed time window (see also figure
2) in a 2D projection of the MEG sensors layout (open black circles), for the simulated data generated as the superposition of the habituating activity (see figure
2) of the ECDs depicted in figure
1 and the contaminating spatially and temporally correlated background noise, at the overall SNR=0.1. Middle: Spatial distribution of the slope coefficients of 1-st degree polynomials fitted to the multichannel estimates of ψ reflecting the trial-to-trial variability of R. Sensors marked with blue-filled circles denote the negative slopes significantly different from zero at the 0.05/245 significance level, where 245 is the number of analyzed channels, revealing a clear habituation. The exact color of a circle reflects the value of the slope. Bottom: The estimate of the temporal covariance T of the noise.