Draws the design-matrix columns as time series in stacked small multiples that share one time axis. Each event regressor gets its own row, coloured by condition (designs with more than 12 event columns get one row per event term instead). Baseline regressors are drawn in grey, one row per baseline term (drift, nuisance). Run-specific columns are drawn only within their own run, and no line is joined across a run boundary. Run intercepts are omitted, since a constant carries no temporal information.
Usage
# S3 method for class 'fmri_model'
plot(x, baseline = TRUE, ...)