First, to load the package, type the following command in the R console:
The ERP study which will illustrate this tutorial was motivated by the study of the electrophysiological process associated with directed forgetting. The study used an experimental paradigm similar to that described in Lee et al. (2013) to investigate people’s ability to intentionally remember or forget items that have been presented. A trial in the experiment consists of two phases. In the study phase of the experiment, n human participants were instructed (with a ‘+’ or ‘X’ cue, respectively) to either remember or forget a stimulus word that had been displayed briefly on a computer screen. ERPs were recorded throughout each of 90 trials–half for to-be-remembered (TBR) and half for to-be-forgotten (TBF)–each lasting for one thousand milliseconds (ms). ERP amplitudes recorded once per ms from nine electrode positions – 3 each from frontal, central and posterior regions – during the study phase were analyzed. It is conjectured that brain activations would be different depending on whether participants were asked to remember or to forget. For each electrode position, the research question can be cast as a large-scale significance analysis of the relationships between the ERPs and the instruction (TBF or TBR), using paired data.
The ERP dataset erpcz can now be loaded:
You can have more information about this dataset in the corresponding help file: