In neuroconductor-devel-releases/eegUtils: A collection of utilities for EEG analysis

This package was created to allow the analysis of EEG data in R. The code in this vignette was previously published on Matt's blog.

Downloading a bdf

Two example Biosemi bdf files can be downloaded from the producer's website. To download and unzip example bdf files use:

url_bdf_zip <- "https://www.biosemi.com/download/BDFtestfiles.zip"
temp <- tempfile()
download.file(url_bdf_zip, temp)
unzip(temp)
unlink(temp)

Loading a bdf file

library(eegUtils)
library(dplyr)

bdf_filename <- "Newtest17-256.bdf"
bdf_data <- import_raw(bdf_filename)

The file is now loaded. You can see its structure

str(bdf_data)

Pre-processing

eegUtils allows loading the bdf files, selecting channels

my_data <- bdf_data %>%
  select_elecs(c("A1", "A2"), keep = FALSE) %>% # remove channels
  reref_eeg(ref_chans = "average") %>% # re-reference
  iir_filt(low_freq = 0.1, high_freq = 40) %>% # band-pass filter
  epoch_data(255, c(-.2,.2)) # epoch: choose a trigger and time limits

Figures

Create a butterfly plot showing data from all the electrodes

plot_butterfly(my_data, baseline = c(-.2, 0), time_lim = c(-.1, .2), legend = FALSE)

Or the timecourse of a single electrode

plot_timecourse(my_data, electrode = "A3", baseline = c(-.2,0), time_lim = c(-.1, .2))

How about an EEGLAB style ERP image?

erp_image(my_data, electrode = "A9")

neuroconductor-devel-releases/eegUtils documentation built on May 5, 2020, 3:49 a.m.