One challenge in the analysis of event-related potentials
(ERPs) is to identify task-related differences in scalp
topography. The multivariate Partial Least Squares (PLS)
analysis was used to identify the spatiotemporal distribution
of ERP differences related to experimental manipulations.
Two simulations included latency shifts and amplitude changes
at peaks with temporal overlap. PLS identified effects
only at modeled timepoints and electrodes. In contrast,
principal components analysis identified differences at
most timepoints. We also demonstrated that PLS identified
combinations of waveform differences, not isolated sources.
ERP components in an auditory oddball task were also assessed
with PLS. The primary distinction was between ERPs on hit
and correct rejection trials, expressed at multiple timepoints
and electrodes. PLS provides a mechanism to describe experimental
differences in ERP waveforms, simultaneously across the
head.