Event-related potentials are one of the simplest ways of representing event-locked EEG data. Imagine a very simple visual experiment in which participants have to respond to pictures of objects. You set up the experiment so that an event trigger is sent to your EEG recording system at the time the picture flashes up screen. Then, afterwards, you extract epochs around those triggers to get a bunch of seperate epochs, each time-locked to the onset of the stimulus.
As mentioned in my last post, I’ve been working on a package for EEG analysis in R called eegUtils. I’d mostly been focusing on relatively simple visualization tools: topographical plots - ERP Visualization: Creating topographical scalp maps: part 1. But one thing was really bugging me - how the data gets into R in the first place. Sure, it’s nice pre-processing data in other packages - EEGLAB or MNE-Python - and then transferring the processed data across to R.
A few months ago I wrote a post about how there isn’t really a killer EEG analysis package for R, and that many of the things you typically want to do are not really implemented yet. So I’ve started to implement several functions myself and incorporate them into my own package, currently called eegUtils. I’ll maybe come up with a catchier name at some point before I get to the stage of trying to get it on CRAN.