FieldTrip made easy: An analysis protocol for group analysis of the
auditory steady state brain response in time, frequency, and space
Popov, T., Oostenveld, R., & Schoffelen, J.-M.
FieldTrip made easy: An analysis protocol for group analysis of the auditory steady state brain response in time, frequency, and space. Frontiers in Neuroscience, 12
: 711. doi:10.3389/fnins.2018.00711.
The auditory steady state evoked response (ASSR) is a robust and frequently utilized
phenomenon in psychophysiological research. It reflects the auditory cortical response
to an amplitude-modulated constant carrier frequency signal. The present report
provides a concrete example of a group analysis of the EEG data from 29 healthy human
participants, recorded during an ASSR paradigm, using the FieldTrip toolbox. First, we
demonstrate sensor-level analysis in the time domain, allowing for a description of the
event-related potentials (ERPs), as well as their statistical evaluation. Second, frequency
analysis is applied to describe the spectral characteristics of the ASSR, followed by
group level statistical analysis in the frequency domain. Third, we show how timeand
frequency-domain analysis approaches can be combined in order to describe
the temporal and spectral development of the ASSR. Finally, we demonstrate source
reconstruction techniques to characterize the primary neural generators of the ASSR.
Throughout, we pay special attention to explaining the design of the analysis pipeline
for single subjects and for the group level analysis. The pipeline presented here can be
adjusted to accommodate other experimental paradigms and may serve as a template
for similar analyses.